Audio Transformer Design and Analysis
dang...@earthlink.net
Study performed by John Atwood, MSEE
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SUMMARY OF RESULTS
Audio Output Transformer Fidelity
Rated A - F, A=BEST, F=WORST
(See above URL's for measurement details)
Best Rated Audio Output Transformers (alphabetical order):
Model Name Rating
Acro UL-2 A
AR D-76A A
Fisher 50A A
Fisher SA-1000 A
Heath W-6M A
Knight 60 A
Madison Fielding 360 A
Marantz 8B A
Marantz 9 A
Pilot AA-908 A
Quicksilver (8417) A
RC-500 A
Scott LK-150 A
Scott LK-49 A
S-152A A
MAGNEQUEST
Magnequest transformers are a current topic of interest. AFAIK,
Acrosound/Magnequest currently owns reproduction rights for vintage
Altec and Peerless audio output transformer designs. For complete
information, contact the owner, Mike LeFevre.
Ratings for Magnequest aka Acrosound aka Peerless aka Altec
Audio Output Transformers
A=BEST, F=WORST (alphabetical order)
Model Name Rating
Acrosound TO-610 A/D
Altec 260A (Peerless) C
Altec 1568 (Peerless) C
Altec TJ-211B E
Altec TL-217B F
Altec TM-255 C
Peerless 16221 N/A
Peerless 16311 E
Peerless 16497 C
Peerless 16589 E
Peerless S-240-Q C
Peerless S-265-Q C
Peerless S-265-Q (2nd) B
AFAIK, "Acro" is another abbreviation for Acrosound et. al.
Acro UL-2 A
Acro TO-310 D
Acro TO-330 D
Worst Rated Audio Output Transformers
A=BEST, F=WORST (alphabetical order):
Model Name Rating
Ampex 6446R1 F
Heath A-9 F
Heath AA-121 F
HK 250 F
IPC (Peerless?) F
Altec TJ-211B F
RECOMMEND BOOKLIST, AUDIO TRANSFORMER DESIGN AND ANALYSIS
1. a. Transformer Design and Manufacturing Manual
b. Audio Transformer Design Manual
Robert. G. Wolpert
Transformer Design Services
5200 Irvine Blvd., #107
Irvine, CA 92720
714-838-6817
Two spiral bound booklets: Need to buy together because b) presumes
knowledge from a).
2. Reuben Lee
Electronic Transformers and Circuits
ISBN 0-471-81976-X
3. Colonel Wm. T. McLyman
Transformer and Inductor Design Handbook
ISBN 0-8427-6801-9
4. Jerry Sevick
Transmission Line Transformers
ISBN 1-884932-66-5
5. Magnetic Circuits and Transformers
Staff of the Electrical Engineering Department
Massachusetts Institute of Technology
Copyright 1943
Reference 1) has the best practical examples. Reference 5) has the
best theory and analysis.
MODERN TRANSFORMER MATERIALS AND DESIGN
Information on modern transformer materials, design and construction
may requested free of charge to qualified persons, on the following
websites:
Magnetics Incorporated:
http://www.mag-inc.com/
National Arnold Magnetics:
http://www.namcores.com/
NAM will supply free magnetic design software to qualified persons.
Additional books and magnetic design software may be obtained from:
http://www.kgmagnetics.com/kgbook2.htm
PERSONAL EVALUATIONS
In response to a request for personal ownership/listening evaluations
of McIntosh, Dynaco, Altec/Peerless, Partridge:
McIntosh
I have owned four units, MC-240, MC-275, MC-2505, MC-2105.
Probably the best audio output transformers I currently own are the
MC-2105 OPT's. This OPT uses the autotransformer configuration, has a
very low turns ratio, very low impedance, very wide bandwidth. It
comes about as close to a "transparent" and distortionless audio OPT
as I have heard to date.
Dynaco
I currently own (2) units with the Dynaco A-431 audio output
transformer, and they good but not spectacular.
Altec/Peerless
I currently own a number of components with Altec/Peerless
transformers, primarily pro audio sound reinforcement and public
address equipment. The worst sounding audio output transformers I
currently own would be the Peerless 16802 models, in (2) Altec 1590,
200W, public address amplifiers. These transformers are not high
fidelity.
Partridge
I do not currently own audio equipment with Partridge audio output
transformers.
Regards,
Dangerdave
George R. Gonzalez
dang...@earthlink.net wrote in message
<37a35f8d...@news.earthlink.net>...
>ANALYSIS OF 80+ TUBE AUDIO OUTPUT TRANSFORMERS
>Study performed by John Atwood, MSEE
It's reassuring to see that in this uncertain world, some things don't
change.
You can depend on them day in and day out.
One thing you can depend on, DangerDave will screw up every time.
If you look at the charts, you'll see a lot of numbers. Numbers are a
measure
of QUANTITATIVE data. For example, the -3db limits are interesting numbers.
Then there's a column of letters, which apparently are a QUALITATIVE
guesstimate of how a 10Kc square wave "looks".
Now most every MSEE would look at the numbers. Dave, not being much of
anything in the electrical realm, gets fuzzy eyeballs any time anything as
hard and immutable as a number crosses his gaze. He focused in on the A-F
letters. Big deal.
Any real MSEE would know that a square wave is made up of many harmonics,
all in the proper phase relationship. Any real MSEE would also know that
you can make a square wave look very un-square just by rotating the phases.
Any real MSEE would also know this doesnt make the tinyiest bit of
difference in how the waveform sounds.
The ear is insensitive to phase at frequencies above a few 100 Hertz.
A real MSEE might surmise that a transformer that goes way out, to say 54Kc,
but then drops off suddenly, would have a poor 10Kc square wave response.
This is because a sudden drop almost always requires considerable phase
shift.
On the other hand, a tranny that slopes off sloooowly, to a -3db point at
34Kc, may show a much better square wave response. This is because the
closer a tranny comes to having a slow "gaussian" dropoff, the closer will
its phase response be to perfect.
That's why transformers that have very good frequency characteristics
(frequency is something the ear is very good at noticing), for example the
Heath A-9, (two of which I have right here on the shelf.), may get an "F" in
the square wave phase (which the ear is totally deaf to) column.
Leave it to Dave to pick the least quantifiable, the most subjective,and the
most useless measurement possible.
Regards,
George
Brian McAllister
>ANALYSIS OF 80+ TUBE AUDIO OUTPUT TRANSFORMERS
>Study performed by John Atwood, MSEE
>
>Page 1
>http://home.earthlink.net/~dangerdav/tranny1.jpg
>
>Page 2
>http://home.earthlink.net/~dangerdav/tranny2.jpg
>
I wonder if he has permission from the copyright owner to publish his
intellectual property.
>
>SUMMARY OF RESULTS
>
>Audio Output Transformer Fidelity
>Rated A - F, A=BEST, F=WORST
>(See above URL's for measurement details)
I see, the sole indicator of a transformer's fidelity is its 10khz
square wave response, driven by 6550s.
>
>Best Rated Audio Output Transformers (alphabetical order):
>
>Model Name Rating
>
>Acro UL-2 A
>AR D-76A A
>Fisher 50A A
>Fisher SA-1000 A
>Heath W-6M A
Conveniently fails to note that this is a Peerless 16431, which
his own source indicates.
>Knight 60 A
>Madison Fielding 360 A
>Marantz 8B A
>Marantz 9 A
If these Ratings are indeed truly indicative of absolute sonic
quality, why did Marantz, on the 8B and 9 modify the square wave
response, through factory adjusted feedback, to give a characteristic
best described in the definition of "C"? I guess they dumbed it down
so as not to embarass other manufacturers <g>
Since the median "rating" is between C and D, I guess it would be fair
to conclude from these data that the rating for the average Altec or
Peerless transformer, including transformers not meant for high
fidelity applications, is higher than most.
>AFAIK, "Acro" is another abbreviation for Acrosound et. al.
>
>Acro UL-2 A
>Acro TO-310 D
>Acro TO-330 D
Yes these are terrible transformers. That is why no-one wants
the EICO HF-60s that use them.
>
>
>
>
snip
>
>
>
>Altec/Peerless
>
>I currently own a number of components with Altec/Peerless
>transformers, primarily pro audio sound reinforcement and public
>address equipment. The worst sounding audio output transformers I
>currently own would be the Peerless 16802 models, in (2) Altec 1590,
>200W, public address amplifiers. These transformers are not high
>fidelity.
By definition, the equipment mentioned above is not high fidelity and
was not designed to be. My Plymouth Voyager won't go from 0-60 in 5
seconds, what does that prove?
>
>
I make no claims to engineering or design ability. I am primarily
interested in vintage tube audio, its repair and restoration. I have
built some amps of my own (other peoples designs) but not in the past
35-40 years.
Brian McAllister
Durham NC
Vintage Radio and Audio Web Pages
http://mcallister.simplenet.com
Grover Gardner
on the test sheets, perhaps because the tests don't claim to judge *overall*
qualitative performance (?). If the point is that Magnequest is stupid to use
Peerless, Altec or Acro designs because they are intended for industrial use
and basically suck, okay, your crude interpolation of ONE area of the data
MIGHT support this. But MQ doesn't make ANY of these transformers (except the
Dynaco replacement models). They currently offer two models based on the
Peerless 20-20 series, the 275 and 271, neither of which are listed in these
tests. So where does that leave us?
Now, the H-K Coronet OPT gets a B--that's pretty good, I guess someone ought
to track down the patent to this puppy. Of course, it rolls of at 130 cycles,
but hey, it got a B--that would indicate pretty good "fidelity" in your own
table, no?
As for the new materials section, this is very interesting, but how much does
this stuff cost? Can affordable transformers be made from it? AFAIK,
Magnequest isn't the only manufacturer sticking to "old-fashioned" materials.
Why aren't other companies using this new stuff, like Tamura, Tango,
ElectraPrint, Black Arts, Lundahl, Sowter, etc. etc.--and why does MQ come in
for special criticism?
--
Grover Gardner
gro...@postoffice.att.net
Grover Gardner
>
> Grove: quick note... was at Potomac Speedway last evening... is 301 South down
> past the Bay Bridge always a parking lot???
On a Friday night in summer? Yes indeed. Shore traffic. And don't try to go
back on Sunday afternoon, either...
--
Grover Gardner
gro...@postoffice.att.net
postm...@triodeel.com
> ANALYSIS OF 80+ TUBE AUDIO OUTPUT TRANSFORMERS
> Study performed by John Atwood, MSEE
What a complete and utter load of crap.
Thank God you unloaded this *here*, on AGA you'd
be torn to pieces. Of course, you don't have the guts to
post on AGA or RAP, they'd eat you alive.
Dave,I don't hate you. Please, get some help, now.
Check out our upgrade boards for Dynaco (TM) ST70, Mk2 & Mk3...
http://www.triodeel.com/dynaco.html
Ned Carlson Triode Electronics "where da tubes are!"
2225 W Roscoe Chicago, IL, 60618 USA http://www.triodeel.com
ph 773-871-7459 fax 773-871-7938
12:30 to 8 PM CT, (1830-0200 UTC) 12:30-5 Sat, Closed Wed & Sun
Kurt Strain
>Dave,I don't hate you. Please, get some help, now.
That's pretty good of you, Ned. I agree with the sentiment,
but he's looking for fights right now and he's not going to
be told to do anything. I suggest the kill file. Don't let this
insanity spread any further than necessary I say. You
can't win arguments with a man who gives no thought
to your statements. So I don't argue there anymore.
Enough said.
Kurt
dang...@earthlink.net
>I make no claims to engineering or design ability.>
>Brian McAllister
>Durham NC
That is self evident.
Regards,
Dangerdave
Acrosound
>>RECOMMEND BOOKLIST, AUDIO TRANSFORMER DESIGN AND ANALYSIS
1. a. Transformer Design and Manufacturing Manual
b. Audio Transformer Design Manual
Robert. G. Wolpert
Transformer Design Services
5200 Irvine Blvd., #107
Irvine, CA 92720
714-838-6817
Two spiral bound booklets: Need to buy together because b) presumes
knowledge from a). <<
Interesting that you would list this as your first selection. Perhaps you did
not know that Mr. Wolpert was the chief engineer for Peerless Transformers for
many, many years.
So I find it interesting that first you claim that "old designs and techniques"
are obsolete. then you further claim that Peerless tranneys were the "bottom
of the barrel" in terms of performance and design... and then you recommend the
two texts written by the former chief engineer of the firm.
BTW... if "oldness" is a strike... then perhaps Mr. Wolpert (god bless him) who
is a very healthy and robust 80+ ( IIRC ) year old ought to "hang it up", heh
Dave????
>>2. Reuben Lee
Electronic Transformers and Circuits
ISBN 0-471-81976-X<<
The first edition of this book was published in 1948. A 3rd edition was
republished in 1988 (hope I have the date right)...
the third edition very closely follows the text of the first edition.
>>3. Colonel Wm. T. McLyman
Transformer and Inductor Design Handbook
ISBN 0-8427-6801-9<<
Mr. McLyman wrote a host of excellent articles back in the fifties.
>>4. Jerry Sevick
Transmission Line Transformers
ISBN 1-884932-66-5<<
Not fimiliar with this book or it's author.
>>5. Magnetic Circuits and Transformers
Staff of the Electrical Engineering Department
Massachusetts Institute of Technology
Copyright 1943<<
You got it Dave.... 1943.... fifty six years ago. Throw away material???
Obsolete???
Where are all the modern materials and references in materials and designs that
you've been promising?
>>MODERN TRANSFORMER MATERIALS AND DESIGN
Information on modern transformer materials, design and construction
may requested free of charge to qualified persons, on the following
websites:<<
Of the vendors you list Dave... what "new" and "revolutionary" materials have
they introduced as "new" products in say the last twenty or thirty years that
are appropiate for audio transformers???
>>PERSONAL EVALUATIONS<<
>>In response to a request for personal ownership/listening evaluations
of McIntosh, Dynaco, Altec/Peerless, Partridge:<<
>>Dynaco<<
>>I currently own (2) units with the Dynaco A-431 audio output
transformer, and they good but not spectacular.<<
What could you tell us Dave about the design, materials or methods of
construction for the Dynaco transformers?
Do you know how they are interleaved? Do you know what insulation materials
they use? what grade of laminations they use? How are they stacked?
Are there any reverse windings in the coil? If so, why?
What impregnant did they use?
What is the max flux density at full power at 20 hertz? What is the OCL of the
primary windings? What percentage UL taps are employed?
What is the measured bandwidth of the output transformers proper? And under
what test conditions?
>>Altec/Peerless<<
>>I currently own a number of components with Altec/Peerless
transformers, primarily pro audio sound reinforcement and public
address equipment. The worst sounding audio output transformers I
currently own would be the Peerless 16802 models, in (2) Altec 1590,
200W, public address amplifiers. These transformers are not high
fidelity.<<
Dave... read Ned's remarks about a big company specializing and building
transformers to suit the needs of their clients. Peerless built everything
from table radio quality audio outputs to 200 KW output tranneys for broadcast
applications. From tranneys where you could fit several into your shirt pocket
to units that weighed literally tons of pounds each.
If you limit your experience to the "sound reinforcement" trans then you should
not speak of the hi-fi units.
Try out some of the 20-20 Plus Series. These were introduced in 1952. On
paper specsmanship numbers approach they fare very well. Peerless was
conservative and rated many of the units for a -1db point at or above 100KHZ.
We have built units from this series and had them tested by William Chater (who
wrote an article using one of our trans in a recent issue of GA). IIRC, the
-1db point was around 160 KHZ.
Primary inductance for this series of transformers is designed at 100 henries
per thousand ohms of impedance. Leakage inductance at 1 mh per thousand ohm of
primary impedance.
The windings are fully balanced with even the secondary windings having
balanced capacitance to ground from the CT.
Leakage and capacitances are very highly balanced btwn both halves of the
primaries to either half of the secondary or to the whole of the secondary.
The Heath W6M which you mention above as having an excellent output transformer
was also designed and built by Peerless. It is, as another poster has already
pointed out, identified by part #16431. The secondary on this unit is wound as
a trifilar unit (you wind three conductors at one time).
If your sincerely interested in learning more about the vintage Peerless
tranneys (limiting ourselves to just their offerings as "output" tranneys)...
then check out some of the following units as representative of their hi-fi
efforts.
S-226-Q
S-230-Q
S-240-Q
S-245-Q
S-265-Q
S-275-Q
or the 16277, 16258, 16340, 16747, the Hadley PP EL34 amp (forget the part
number off hand), 16604, 16607, 16589, 16554, and slews of others. The Heath
W1, W2, W5, and W6 all used Peerless transformers.
or check out any of the 20-20 Plus series.
I was however surprised to learn that you could only identify one particular
amp by model number made by Altec and on which you are apparently basing your
"judgements".
One design for Altec (peerless was a division of Altec until 1981) in no way
touches the surface of what the design archives hold. It is a much bigger
world than one David.
>>Partridge<<
>>I do not currently own audio equipment with Partridge audio output
transformers.<<
Is "currently" a qualifier? Have you ever owned any Partridge transformers?
If so I would be curious which models you have auditioned.
Dr. Partridge was one of the real giants in the field of audio magnetics (as
well as other magnetic/xfmr pursuits). I am surprised that you do not list his
four part series on harmonic distortion in audio transformers on your read
list. I would highly recommend this reading. Are you fimiliar with Dr.
Partridge's academic research and findings?
Another add to your recommended reading list ought to be Dr. Sowter's seminal
papers (written in 1945) I beleive on the behaviour of nickel laminations in
audio (as well as other types) of transformers. This guy was another giant.
A third person who might be worthy of being included on your reading list is
the volumes of articles and books authored by the late Norman Crowhurst. You
can find excerpts of his work and furhter references to the him in Radiotron.
A brilliant author and magnetician. This man literally wrote thousands of
articles on audio topics with a special emhasis, knowledge, and insight with
audio magnetics in particular.
Still would like to hear from you David on what "new" materials in insulations,
laminations, core shapes, potting compounds and etc that you stated separated
"contemporary" transformers from their earlier brethen.
MSL
Acrosound
>>As for the new materials section, this is very interesting, but how much does
this stuff cost? Can affordable transformers be made from it? AFAIK,
Magnequest isn't the only manufacturer sticking to "old-fashioned" materials.
Why aren't other companies using this new stuff, like Tamura, Tango,
ElectraPrint, Black Arts, Lundahl, Sowter, etc. etc.--and why does MQ come in
for special criticism?<<
Grover: a more basic challenge which Dave has ignored is that he has claimed
that the transformer world is full of "new" and "contemporary" materials not
available to the ancients hailing from the fifties or sixties. In particular
Dave said that there were many "new" developments in core materials, core
shapes, methods of making cores, insulations, impregnants, and etc.
So far he has remained mute on what these "new" materials are. So how one (as
a consumer) is to seek out these new, advanced materials escapes me.
Many of the materials (see my previous post on materials) seen as "new" perhaps
by some consumers really are not at all "new" in the sense of being introduced
recently to the transformer world. Dave mentioned "torroidal winding" as one
new development... new about fifty or more years ago maybe....
Some of the current materials which are "popular"... like say the nickel
tranney cores... nickel dates back commericially to the late thirties at least.
ATT (Western Electric) was a real pioneer in the development of low distortion
nickel laminations.
Many of the "cool" insulations go back for several decades at least.
Cold rolled steel (so you could achieve grain orientation of the silicon family
of steel laminations) was commercially introduced in 1952 or so. Prior to this
the electrical grades of steels were hot rolled. M6 did not (and I beleive the
first designation for the first grain oriented silicon steel was the grade M7)
differ metallurgically from M15... except for the cold rolled grain
orientation. M15 is a non oriented silicon steel that you can not for love or
money purchase today (who nows...maybe a big enough order could get some steel
mill to make it) from any of the established suppliers (at least in the US).
Grove: quick note... was at Potomac Speedway last evening... is 301 South down
past the Bay Bridge always a parking lot???
see ya guy,
MSL
bobcx
Brian McAllister <mcall...@mindspring.com> wrote in message
news:37a37201....@news.mindspring.com...
> On Sat, 31 Jul 1999 21:23:11 GMT, dang...@earthlink.net wrote:
>
> >ANALYSIS OF 80+ TUBE AUDIO OUTPUT TRANSFORMERS
> >Study performed by John Atwood, MSEE
> >SUMMARY OF RESULTS
> >
> >Audio Output Transformer Fidelity
> >Rated A - F, A=BEST, F=WORST
> >(See above URL's for measurement details)
> I see, the sole indicator of a transformer's fidelity is its 10khz
> square wave response, driven by 6550s.
Which in and of itself is not an indication of sound quality. But even if it
was...
dangerdav fails to realize that the transformers were not matched to the
circuit at all, just dropped in, nothing changed or optimized.
The output tubes are PP 6550s and most of the transformers were not designed
for this application.
What's even funnier about dangerdav is that almost every time he posts his
BS he shoots himself in the foot! Just take a look...
The Heath W6-M using the Peerless 16431 as you point out Brian gets an "A"
rating.
This transformer was designed by Peerless for PP 6550s for use in a hi-fi
amplifier!
Gee whiz dangerdav, I guess Peerless knew what they were doing after all!!!
next
BC
P.S. Dangerdav, the test you put up is someone else's NOT YOURS, and it is
ten years old!
We were looking forward to YOUR TEST of MODERN TRANSFORMERS using MODERN
MATERIALS!!!
Are you're having trouble fabricating it?
If so, try contacting Bill May maybe he can help you!
dange...@my-deja.com
Grover Gardner <gro...@postoffice.att.net> wrote:
> Well, you've sort of ADDED the phrase "audio fidelity"
There was no "addition" involved. I summarized the results, not
"summed" them. If you want to review the raw data instead, simply click
to the upload's. No need to thank me. Your appreciation is obvious,
and quite gracious indeed :-)
The 10kHz qualitative waveform fidelity analysis John employed is a good
indicator. The other things he measured are very common audio
transformer test points. He did a very good study, requiring quite a
bit of work, and objectively measured more transformers than any other
comparative audio OPT analysis I am aware of. And he did it without
personal or emotional bias, so the results are useful.
If you want to post a comparative audio output transformer analysis, to
your own personal standards, please feel to obtain the transformers and
measure them any way you like.
There are numerous other objective indicators of transformer fidelity as
well. Please feel free to review the references I posted. For
"classic" transformer quality analyses, the MIT reference is pretty
good.
And of course, transformers are non-linear devices, well modeled by
modern non-linear methods, a few of which I mentioned in a concurrent
post.
>tests don't claim to judge
*overall*
> qualitative performance (?).
The tests claim what they claim. If you want to do a subjective
listening test, get ahold of all the transformers as John did, and do
one. I would look forward to reading your posted results.
>If the point is that Magnequest is stupid to use
> Peerless, Altec or Acro designs
Please feel free to draw any conclusions you wish. Personally, I would
suggest you stick to measurements, tests, objectivity and such, and let
the readers draw their own conclusion.
> because they are intended for
>industrial use
AFAIK, the transformers you mentioned were never intended for industrial
use. And if you will read the thread, uploads, and references, nowhere
does it say they were. Probably what you are confusing is the term
"industrial", with descriptors like commercial, as in commercial public
address amplification.
> and basically suck, okay, your crude interpolation
The summary did not employ interpolation methods. Please review.
Also, as I already stated, if you want to draw the conclusion that
Magnequest sucks, please do so. However, the post is not about
Magnequest. Many transformers were measured, the results reported,
design and analysis references were given, modern transformer materials,
design and construction references were supplied, and so on.
This is what "The Magnequest Mob" was demanding, if I may be so bold.
The "suck" remark, and conjecture, is yours alone.
Regards your price questions: Please contact transformer material
manufacturers for current pricing information. Better materials than
Fe-Si do usually cost more. Regards audio output transformer retail
costs, however, there is more to transformer cost than just raw magnetic
materials. Many boutique audio transformers manufacturers have retail
price points far in excess of electronic industry standards. Obviously,
more than just raw magnetic materials cost is causing the
price/performance disparities.
In the general case, the cost and quality of manufacturerd goods is
usually improved by factors such as volume, modern production methods,
modern process controls, modern design methods, etc. Virtually all
companies in the manufacturing sector follow this model. Perhaps if you
look to the audio and electronic industry trade journals, you might find
some in-depth explanations for the price disparities between boutique
audio transformers and modern transformer products of equivillant or
better performance.
I would look forward to reading your research results, if you choose to
pursue your cost concerns further.
> AFAIK,
> Magnequest isn't the only manufacturer sticking to "old-fashioned"
materials.
> Why aren't other companies using this new stuff, like Tamura, Tango,
> ElectraPrint, Black Arts, Lundahl, Sowter, etc. etc.--
Well, I'm not sure what "stuff" you are referring to. I would suggest
you examine some of the references, request the magnetic product design
literature, review the many materials and their performance differences,
and get a bit more specific about which "stuff" you are comparing to
which other "stuff".
Regards alternative transformer materials, other than Fe-Si, which is
the least expensive magnetic material available, some of the boutique
companies you mentioned use them, but most of the manufacturers of
advanced transformer designs are not restricted to just the boutique
audio sector. Please review the references and URL's provided, and the
many similar links available though web search engines.
and why does MQ
come in
> for special criticism?
Don't ask me. Your post contains the stuff about Magnequest sucks and
so on.
> Grover Gardner
> gro...@postoffice.att.net
Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.
JLSEM
>Some of the current materials which are "popular"... like say the nickel
>tranney cores... nickel dates back commericially to the late thirties at
>least.
> ATT (Western Electric) was a real pioneer in the development of low
>distortion
>nickel laminations.
Permalloy (78% nickel) was developed at Bell Labs in the early 'twenties by a
team of engineers headed by a Mr. Arnold (name sound familiar?).
Other than Metglas, the only significant recent development in core materials I
can think of is Dynamax, which work was done at GE in the mid 'fifties. If you
think Permalloy is expensive to make...
John
dange...@my-deja.com
> So far he has remained mute on what these "new" materials are. So how
one (as
> a consumer) is to seek out these new, advanced materials escapes me.
Perhaps you might try what everyone else does, and contact the
manufacturers yourself? If you find it difficult to click on the URL's,
or use the telephone, I would be glad to provide you with basic
operating instructions. Or perhaps your common day laborers will handle
the inconsequential details for you. After all, as owner, perhaps the
minutia of magnetic materials are unworthy of your valuable time and
efforts. Indeed, those plebeian "hobbyists" probably can't tell the
difference anyway.
> Some of the current materials which are "popular"... like say the
nickel
> tranney cores... nickel dates back commericially to the late thirties
at least.
Obviously! Those ridiculous "materials science engineers" have been
asleep for the last 60 years. Everyone who's anyone knows that.
> ATT (Western Electric) was a real pioneer in the development of low
distortion
> nickel laminations.
Pioneer, as in the days when "hi-fi" meant listening to Amos and Andy,
Walter Winchel, Kit Kaiser, over "amplitude modulated" radio broadcasts?
Fade in, fade out. Scrrrrrratch, hummmmmm, roarrrr, whistle, pop....
"Lord o' Mercy! There's a human voice out from the radio set, Mother!
What on Earth?"
Pioneer, indeed.
I hope my lowly posts on audio transformer design and analysis don't
disturbe your auto racing career too much, Mike. I wouldn't want to
interfere with what's *really* important.
Regards,
Dangerdave
dange...@my-deja.com
postm...@triodeel.com wrote:
> On Sat, 31 Jul 1999 21:23:11 GMT , dang...@earthlink.net wrote:
> > ANALYSIS OF 80+ TUBE AUDIO OUTPUT TRANSFORMERS
> > Study performed by John Atwood, MSEE
>
> Thank God you unloaded this *here*, on AGA you'd
> be torn to pieces. Of course, you don't have the guts to
> post on AGA or RAP, they'd eat you alive.
>
> http://www.triodeel.com/dynaco.html
>
> Ned Carlson Triode Electronics "where da tubes are!"
> 2225 W Roscoe Chicago, IL, 60618 USA http://www.triodeel.com
> ph 773-871-7459 fax 773-871-7938
> 12:30 to 8 PM CT, (1830-0200 UTC) 12:30-5 Sat, Closed Wed & Sun
>
Well, thank you Ned, for the most courteous and gracious reply. I
was glad to post the information that you requested.
And it's good to be proven wrong by posts like your own. Clearly, the
small Magnequest Mob attempting to dominate RAT, often referred to as
underemployed electric guitar repair technicians, flamers, spamers,
and the like, is nothing but fiction. The objective and intelligent
manner in which you handle matters of transformer design and analysis,
as demonstrated above, illustrates that most conclusively. And
additionally, is quite an incentive for hobbyist to purchase fine
Magnequest transformer products directly from you, as your
advanced interpersonal skills and open-minded objectivity are so readily
apparent.
Sander deWaal
(after debunking Dave's "claims")
>I make no claims to engineering or design ability. I am primarily
>interested in vintage tube audio, its repair and restoration. I have
>built some amps of my own (other peoples designs) but not in the past
>35-40 years.
This confession is probably enough for DD to say that
you're "not interested in the advance of audio science",
or something like that.
Put on your asbestos suit and hat ! :-)
--
Sander deWaal
c...@wxs.nl
Sander deWaal
<huge snip>
>Still would like to hear from you David on what "new" materials in insulations,
>laminations, core shapes, potting compounds and etc that you stated separated
>"contemporary" transformers from their earlier brethen.
You don't "get it", Mike.
Dave's making claims, and *others* get to prove it.
Odd view of "peer review", if you ask me.
--
Sander deWaal
c...@wxs.nl
Sander deWaal
Acrosound
>>Permalloy (78% nickel) was developed at Bell Labs in the early 'twenties by a
team of engineers headed by a Mr. Arnold (name sound familiar?).<<
Hey, who is this Mr. Arnold guy <g>? Perhaps the founder of Arnold Magnetics?
The same "Arnold" entrprise that was acquired a few years ago by National?
Interesting stuff here John. I mentioned the late thirties as a "safe"
guesstimate of the commercial use of nickel laminations in audio related
transformers. I have a reference somewhere (IIRC in an article written by the
senior Dr. Sowter) that in the late thirties (1938) Bell Labs had "perfected" a
doping of the high-nickels which resulted in a more linear nickel based alloy
lamination material. But it has been a while since I read the article so some
of my dates may be off by a few years.
I did not know that Mr. Arnold was a Bell Labs employee at some point. Lots of
good stuff in materials and design came out of the Bell Labs organization.
My larger point was that there really isn't a lot of quote "new" "contemporary"
core materials out there. Your post also seems to say about the same thing.
>>If you think Permalloy is expensive to make...<<
then try Superpermendur. SP is a cobalt based iron alloy that has, IIRC,
higher perm than even high nickel (70% to 80%) has. It makes the nickel lams
look inexpensive relative to the $200 a pound price quotes I have gotten on SP.
The advantage of the SP vis-a-vis the nickels is that the SP does not saturate
nearly as easily as the nickels.
To use Ned's Dyna Mk. III output transformer example... around 8 pounds of core
material per unit times 200 bongo congos per pound. $1600 at manufacturer's
level for the SuperPermendur core material.
MSL
dang...@earthlink.net
>dange...@my-deja.com said:
>
>>TROLL.
Gee, Sander. You promised to put me in your kill file. Is it
malfunctioning or something?
No matter. The thoughfullness and wisdom of your current response to
"Audio Transformer Design and Analysis" speaks volumes in itself.
Regards,
Dangerdave
Ron Bales
>
>> So far he has remained mute on what these "new" materials are. So how
>one (as
>> a consumer) is to seek out these new, advanced materials escapes me.
>
>
>Perhaps you might try what everyone else does, and contact the
>manufacturers yourself?
Hey, DangerTroll. You are the one who made the assertion, you are the
one to answer it. You stated that there are new materials that Mike
should be using and isn't, what are they.
ROn
Gerald Stombaugh
We, TSC International Corp. purchased Arnold Technologies, Lamination
division about 5 years ago. We also manufacture ferrite cores under
TSC, Ferrite International Corp and powdered iron cores under
Pyroferric Corp.
All located at 39105 N. Magnetics Blvd.
Wadsworth, Illinois, 60083-0399
Gerald Stombaugh
The web site is www.tscinternational.com
Grover Gardner
> There was no "addition" involved. I summarized the results, not
> "summed" them.
You wrote:
> SUMMARY OF RESULTS
>
> Audio Output Transformer Fidelity
> Rated A - F, A=BEST, F=WORST
This is an interpolation. "Summary of results" is misleading. You merely
relabelled on column of the test data. The phrase "audio output transformer
fidelity" is found nowhere on the test data sheets. Nor are the words "best"
or "worst". You interpolated qualitative phrases and words which are not in
the report.
> The summary did not employ interpolation methods. Please review.
I have. It did. How else would you define "interpolation"?
> Also, as I already stated, if you want to draw the conclusion that
> Magnequest sucks, please do so. However, the post is not about
> Magnequest. Many transformers were measured, the results reported,
> design and analysis references were given, modern transformer materials,
> design and construction references were supplied, and so on.
But you added the following:
> MAGNEQUEST
> Magnequest transformers are a current topic of interest. AFAIK,
> Acrosound/Magnequest currently owns reproduction rights for vintage
> Altec and Peerless audio output transformer designs. For complete
> information, contact the owner, Mike LeFevre.
>
> Ratings for Magnequest aka Acrosound aka Peerless aka Altec
> Audio Output Transformers
> A=BEST, F=WORST (alphabetical order)
Why? No Magnequest transformers were tested. So the "ratings" you've
re-labelled and listed below this heading are not for "Magnequest aka Peerless
aka Altec". They are for Peerless, Acro and Altec transformers. Magnequest
did not exist when these transformers were manufactured. They may have later
purchased the patents and designs, but they did not manufacture the
transformers tested in the report. It seems a little misleading.
--
Grover Gardner
gro...@postoffice.att.net
Acrosound
>>Slight Correction:
>>We, TSC International Corp. purchased Arnold >>Technologies, Lamination
>>division about 5 years ago. We also manufacture >>ferrite cores under
>>TSC, Ferrite International Corp and powdered iron >>cores under
>>Pyroferric Corp.
>>All located at 39105 N. Magnetics Blvd.
>>Wadsworth, Illinois, 60083-0399
>>Gerald Stombaugh
>>The web site is www.tscinternational.com
thanks Gerald. Wasn't there two different Arnold magnetics companies... each
operating independently for many years. The one specializing in stamped
laminations and the other in c-cores and wound (for lack of a better word)
laminations?
Wasn't one of the Arnold companies specialized in the production of nickel
based lams? If I recall correctly wasn't one of them in California and the
other in Illinois?
thanks for any info you might be able to provide,
MSL
bobc
Grover Gardner <gro...@postoffice.att.net> wrote in message
news:37A4A0A4...@postoffice.att.net...
> dange...@my-deja.com wrote:
>
> > There was no "addition" involved. I summarized the results, not
> > "summed" them.
>
>
> > SUMMARY OF RESULTS
> >
> > Audio Output Transformer Fidelity
> > Rated A - F, A=BEST, F=WORST
>
> This is an interpolation. "Summary of results" is misleading. You merely
> relabelled on column of the test data. The phrase "audio output
transformer
> fidelity" is found nowhere on the test data sheets. Nor are the words
"best"
> or "worst". You interpolated qualitative phrases and words which are not
in
> the report.
Thanks for explaining this so clearly Grover.
> But you added the following:
>
> > MAGNEQUEST
> > Magnequest transformers are a current topic of interest. AFAIK,
> > Acrosound/Magnequest currently owns reproduction rights for vintage
> > Altec and Peerless audio output transformer designs. For complete
> > information, contact the owner, Mike LeFevre.
> >
> > Ratings for Magnequest aka Acrosound aka Peerless aka Altec
> > Audio Output Transformers
> > A=BEST, F=WORST (alphabetical order)
>
> Why? No Magnequest transformers were tested. So the "ratings" you've
> re-labelled and listed below this heading are not for "Magnequest aka
Peerless
> aka Altec". They are for Peerless, Acro and Altec transformers.
Magnequest
> did not exist when these transformers were manufactured. They may have
later
> purchased the patents and designs, but they did not manufacture the
> transformers tested in the report. It seems a little misleading.
Dangerdav's motives are very transparent to everyone. He is very jealous of
real people with accomplishments. He tried to con his way into the audio
business with claims that he was this great designer, he was rebuked and
this is his payback.
Pretty sad, but it's the same old net story. Anyone with $20 can do and say
anything and think they get away with it.
Danger has proven over and over again he knows little about tubes and audio,
but he keeps on going. Each successive outburst of bullshit gets more
outrageous.
As we see with DD and others here lying can become very addicting, they are
like junkies who need more and more smack to get high, the liars need bigger
and bigger lies, and have to be more and more abusive to get their fix!
BC
Sander deWaal
Sander deWaal
>Danger has proven over and over again he knows little about tubes and audio,
>but he keeps on going. Each successive outburst of bullshit gets more
>outrageous.
I suspect the problem is that DD knows *too much* about tubes and
audio theory, and *too little* about real life and actually building
an amp.
--
Sander deWaal
c...@wxs.nl
JLSEM
Anything that has to do with exotic magnetic core materials is interesting
stuff, IMHO, especially if it can be applied to audio. I came across a
description of Dynamax in a book on "Magnetic Materials and Their Applications"
by Carl Heck. It reads thusly:
"...a 65% nickel alloy known as Dynamax was developed. The name is intended to
suggest that the dynamic hysteresis loop is especially good and does not
broaden much with rising frequency ( ! )..."
"Dynamax contains, besides its 65% Ni and 33% Fe, some 2% Mo and, to improve
workability, 0.3% Mn. High permeabilities were achieved in strip-wound cores
after a 4 hr annealing in pure dry hydrogen and a slow cooling (for example,
150 K/hr) from 650 degrees C downwards, in a magnetic field of 800-950 A/m. It
was found that the values achieved for maximum permeability, namely about
1,000,000 - 1,600,000 uo, can be improved upon if a second recrystallization
annealing is introduced at 1200 degrees C...."
Obviously, the outstanding property of this material that might make it really
good for audio is the minimal broadening of the hysteresis loop as frequency
increases. I cannot honestly say if this stuff was ever available
commercially.
BTW, Dr. Heck's reputation is somewhat tainted by the fact that, during WWII,
he worked on the development of powdered ferrite cores for Nazi radar
applications. His book has only been out of print for a couple of years,
originally translated and published in English in the early seventies.
Dr. Harold Arnold was the first director of Bell Telephone Laboratories.
Permalloy was first patented in 1917, having been developed by Gustav Elman at
Bell Labs beginning in 1906. Elman was actually the person who led the
investigation of high-permeability nickel-iron alloys there.
John
dange...@my-deja.com
amplifiers.
dange...@my-deja.com
> 1. a. Transformer Design and Manufacturing Manual
> b. Audio Transformer Design Manual
> Robert. G. Wolpert
> Transformer Design Services
> 5200 Irvine Blvd., #107
> Irvine, CA 92720
> 714-838-6817
>
> Two spiral bound booklets: Need to buy together because b) presumes
> knowledge from a). <<
> So I find it interesting that first you claim that "old designs and
>techniques" are obsolete. then you further claim that Peerless
>tranneys were the "bottom
> of the barrel" in terms of performance and design... and then you
>recommend the
> two texts written by the former chief engineer of the firm.
As I already stated, Wolpert's books contain the most hands-on practical
information. That's why I recommend them for DIY guys who want to wind
their own transformers. Guys at your math level, Mike. They are
basically algebra level only, without any knowledge whatsoever of modern
non-linear design methods, contemporary transformer design mathematics
or modern magnetic design software required.
Beyond that, I don't see any point in you lunching off of Wolpert's
work for your own narrow purposes. It is what it is, and if designers
want the books, they will buy them.
> Where are all the modern materials and references in materials and
designs that
> you've been promising?
References/URLs/Links may be traced through section entitled:
"MODERN TRANSFORMER MATERIALS AND DESIGN"
This is self-evident.
BTW: I haven't promised anyone anything. Nor do I intend to. I am
always interested in discussing modern audio transformer design with
interested hobbyists, audio designers, and qualified persons.
Interested to exchange information, and so on. Beyond that, any
"promises" you demand, insinuate, imply, or infer, are yours alone, Mr.
LeFevre. And no designer or hobbyist need be bound by them in ANY way.
Indeed, no experienced or mature person would allow themselves to be.
Surely, as a self-designated corporate executive, you must be familar
with standard minimum business practice regards contracts and
obligations?
> Of the vendors you list Dave... what "new" and "revolutionary"
materials have
> they introduced as "new" products in say the last twenty or thirty
years that
> are appropiate for audio transformers???
hmmm.... Isn't that what you are supposed to be telling the audio
hobbyists and designers?
I find it a bit strange when you ask the hobbyist and designers to
advise YOU, the manufacturer. You are taking the profits, you are
supposed to know. At least, that's the way it has worked with all the
other electronic manufacturers I have worked with during my carrer as a
designer and researcher in the electronics industry.
Until, of course, I ran into the part-time auto racer, philosophy major,
Mike LeFevre, running an "electronics manufacturing corporation" using
his family members and day laborers, all 4 or 5 of them, with 1) No
professional design staff 2) No full time engineers on staff AT ALL 3)
No test and reliability laboratory 3) No materials laboratory 5)
electric guitar repairman as "Sales Representatives", 6) a small "mob"
of guys you telephone constantly to orchestrate flames in RAT, 7)
manipulating a public newsgroup intended for tube audio hobbyists and
designers to get free advertising and marketing for Magnequest alone, 8)
not enough sense to stay out of flame fests with international audio
journalisitsm, much to the dismay of everyone else trying to post here.
No need to go on.
The referenced thread is NOT EVEN ABOUT MAGNEQUEST. You, and your "mob"
just hi-jacked the thread, AS USUAL And you and your "mob", Mr.
LeFevre, turned it into yet another MAGNEQUEST SALES PITCH, the same as
you have been doing here for years.
Magnequest is not a modern audio transformer design company with
competitive products, in my opinion. It's just an old bunch of 1950's
stuff you bought the rights to, cheap, because the parent corporation
didn't want them any more. You aren't even a designer, or engineer at
all. You don't even have a related degree. You are more like a casual
time, high profit, dilettante.
What I, and many other interested persons in tube audio design need, is
a forum to objectively discuss and compare modern audio transformer
design methods, companies, objectively measured results. And many other
design matters as well. Because of you, Mike LeFevre, and your small
"mob" of infamous guys, this NG is ruined regards those purposes.
Simply reviewing the flamer responses to "Audio Transformer Design and
Analysis", the post having nothing whatsoever to do with Magnequest,
except to list a few *measured* test results, demonstrates that directly
and unambiguously.
And, judging by past performance, although you are likely to respond to
this post with another orchestrated "flame fest", I am not very
concerned. Although many audio designers and interested persons are
unwilling to post here, for obvious reasons, some DO read the threads,
and are intelligent enough to draw their own conclusions, independent of
crude, hostile, and ill-informed flamer remarks.
I don't believe I need comment further.
In any event, and with all due respect, I have better design matters to
attend to, as do most of the guys *attempting* to use RAT for tube audio
design and related matters.
Acrosound
> Of the vendors you list Dave... what "new" and "revolutionary"
materials have
> they introduced as "new" products in say the last twenty or thirty
years that
> are appropiate for audio transformers???
::hmmm.... Isn't that what you are supposed to be telling the ::audio
::hobbyists and designers?
The person who claims that there is a whole host of "new" and 'revolutionary"
materials available for audio design (your original thesis Dave) is the one who
has the burden of proof.
In to counter your argument I have already listed many of the core materials
and insulations widely used in the industry and listed approx dates of when
they were commericially introduced to the transformer industry. In most cases
it is forty to fifty years ago... ipso facto defeating your thesis... unless of
course you are willing to share with us which new, stealth materials I missed
out on...
::I find it a bit strange when you ask the hobbyist and ::designers to
::advise YOU, the manufacturer.
I find it a bit odd that you make the original assertion that there is a whole
list of new materials (insulation, potting compounds, and laminations) and then
when asked for proof of your assertion you go "mute" on everyone and started
hurling flames around....
major flames and trolls by Dangerdave deleted
::The referenced thread is NOT EVEN ABOUT MAGNEQUEST. You, ::and your "mob"
::just hi-jacked the thread, AS USUAL And you and your "mob", ::Mr.
::LeFevre, turned it into yet another MAGNEQUEST SALES PITCH, ::the same as
::you have been doing here for years.
Baloney David. You've been flaming me since the inception of this thread and I
have yet to flame you at all. I am simply asking that you provide some proofs
for the claims about "modern materials" that you made.
Additionally, you made some disparaging remarks (with no grounds) about
Peerless and then go on to recommend the text written by the former chief
engineer of the company.
::Magnequest is not a modern audio transformer design company ::with
::competitive products, in my opinion. It's just an old bunch of ::1950's
::stuff you bought the rights to,
oh. we are back to that tune. And the only Peerless/Altec amp
you've heard is a class B public address amplifier and you then go on to
pretend that this singular design (built for an obvious non hi-fi purpose)
captures the many thousands of designs in the Peerless archives.
Like I suggested before you might actually want to audition some of the vintage
Peerless hi-fi iron before passing judgement on them.
::You don't even have a related degree. You are more like a ::casual
::time, high profit, dilettante.
Danger.... could you be kind enough to tell me the academic background of some
of the following people:
David Hafler of Dynaco and Hafler fame. Did he have an engineering degree?
Herbert Keroes of Acrosound. Did he have an engineering degree?
what about Saul Marantz? Avery Fisher? What about Ercel Harrison?
What about the owners of Conrad Johnson? Audio Research?
VTL? Manley Labs? Cary Audio? Convergent Audio Technology? Rogue Audio?
Wright-Sound?
Perhaps a formal degree is not a necessary prerequisite to doing good design
work and building good hi-fi products.
These are the folks who sat down and actually did some constructive work
instead of flaming everyone in sight. The audio community benefitted as well
as the individuals.
What actual, concrete, examples have you designed and /or built lately Dave?
::What I, and many other interested persons in tube audio design ::need, is
::a forum to objectively discuss and compare modern audio ::transformer
::design methods, companies, objectively measured results.
Hey let's do it. please provide the list of modern materials and dates of
introduction into the commericial marketplace and let's discuss in a rational
manner the benefits of the new materials. The same new materials which you
have previously claimed exist and separate the "new" tranney makers from the
"old" tranney makers. But first you must be willing to tell us what these
"new" and "revolutionary" materials are. And then we could evaluate these
"new" materials and talk about their benefits.
::And many other
::design matters as well. Because of you, Mike LeFevre, and your ::small
::"mob" of infamous guys, this NG is ruined regards those ::purposes.
Dave, the above is simply a troll. I love to discuss materials... I wrote a
brief bit about many of the materials used extensively in the transformer
industry today in an earlier response to you... I have not seen you pick up the
electronic pen and enter into a discussion about any of these materials, their
benefits, their limits, their "optimalities" or anything like this.
If this is the nature of discussion you would like to see occurr on this
newsgroup... then, like Nike sez, "Just Do It".
Regarding your NARMX programs or whatever it's acronym is... could you kindly
tell us which audio transformer companies use these programs? Perhaps then we
could elicit from them what they feel the usefulness or value of the programs
are. In other words David... who is on the roster of users for all of these
computer programs?
Am I wasting my breath with this guy???
thanks,
MSL
Kurt Strain
: Am I wasting my breath with this guy???
Yes. But the rest of us are getting better educated by you in terms
of the transformer industry.
BTW, no one even asked why I chose the Peerless transformer over the
other choices available to me. It wasn't the name, it wasn't the
winder, it wasn't who designed it. It wasn't even just because
Henry likes his so much.
It was because of the following reasons:
1. It was designed especially for the 845 in class A PP operation
for a 1KV supply. 1KV is what I want to design for because of
the PS parts I have, and I want the optimum transformer for this,
which the Peerless S-275 is. And I could still go as high as
1.2KV and it remain close to optimal.
2. I have 16 ohm speakers for use with it. I may change speakers to
8 or 4 or even 2 ohm speakers. This Peerless model allows these
changes with max use of the turns of the secondary, and minimizes
insertion loss. ElectraPrint couldn't do this, being optimized to
one impedance only, the Tango and Audio Note do not use all the
turns for anything except the 16 ohm tap.
3. Peerless oversized the transformer to allow much headroom, higher
than ElectrPrint, from the specs I received. It's the highest
power transformer I found, able to go to 70W instead of 40W or 50W.
I think ElectraPrint would wind a special 70W transformer, but still
only one tap to choose.
4. I got more specs about the Peerless to tell me it's what I need
than any of the others, believe it or not. It's less guesswork for me.
5. Audiophiles in Japan regard these particular Peerless models at the
top, preferable in most cases.
Despite the high cost for Peerless in Japan, most of the Peerless
shipment for PP is going to Japan. While America sees the SE amp as
"the ticket" that the Japanese have given re-birth to in the 70's and
80's, the trendy SE amp is not so trendy in Japan as people think. What
is it about? DIY demand is about 90% SE / 10% PP in USA and
60% SE / 40% PP in Japan. The PP amp is valued and thriving in Japan.
I'm interested in giving a high powered PP triode amp my best shot,
as humble and limited as it's going to be, especially for its ability
to drive most any real-world speaker.
I have spoken to Mike on the phone on two occasionas and I can tell he
has passion and pride in his work. It's an honest passion, not a
phony sales dialog, obvious because I can't get him to stop talking
transformers and the amps that use them to lower my long distance bill.
All this AFTER having committed to purchase. I know other manufacturers
are doing very well at their craft, and I do not feel committed to only
buy from Mike because of some organized crime conspiracy some people
seem to dream up around here. I own One Electron and I will be getting
Lundahl interstage transformers, too. Mike, unlike what some deluded
folks seem to think, does not twist my arm to change over. He is just
extremely proud of his business, and his customers seem very pleased.
This kind of pride does have the effect of sensitizing him to criticism.
So what, I say.
If I hate his transformer, I'll let you all know. This is the first
purchase I have made from him. We'll see. The fact is, Mike feels
confident I'll love this, and I'm sure he's not worried about what
comments I'm going to make.
Kurt
"No Magnequest Mob for Me"
bobcx
Kurt Strain <kst...@sr.hp.com> wrote in message
>
> Kurt
>
> "No Magnequest Mob for Me"
Are you sure? I hear pinstripes suits are in fashion this season!
BC
Andre Jute
> I have spoken to Mike on the phone on two occasionas and I can tell he
> has passion and pride in his work. It's an honest passion, not a
> phony sales dialog, obvious because I can't get him to stop talking
>
> Kurt
>
> "No Magnequest Mob for Me"
Are those bees you mentioned the other day breeding yet, Kurt?
Inquiring minds want to know!
--
Andre Jute an...@indigo.ie COMMUNICATION JUTE
http://indigo.ie/~andre/ComJuteF1.html
"an unbelievably comprehensive web site containing
vital gems of wisdom" -- Stuart Perry :: Hi-Fi News & Record Review
Acrosound
Acrosound (acro...@aol.com) wrote:
: Am I wasting my breath with this guy???
to which Kurt Strain replied:
>>Yes. But the rest of us are getting better educated by you in terms of the
transformer industry.<<
When possible I try to give informative helpful responses to questions. And I
do love tranneys, materials (almost to a point of being a materials junkie),
winding machines, big old one ton cast iron fully manual paper cutters... and
showing off all of this stuff. Just ask the fella from DC who came for a visit
last week or so.
On that note anyone who wants a big ass winding machine.. fully manual, wind it
the ole fashion way, by hand... one at a time.... give me a call. It weighs
about 500 pounds or so... and I don't use it any longer... graduated to a
modern hand winder with a DC motor instead of the variable brush shifting AC
motor that the older machine has. It has a great counter on it, all new
bearings in the motor (well two years old) and a rebuilt headstock.... anyone
wanna trade some interesting tubes or a pair of early Heath monoblocks or....?
thanks all,
Mike
Doug Still
Robert A. Heinlein wrote in one or more of his books to "never try to teach a pig
to sing, it wastes your time and annoys the pig".
Doug
Ned Carlson
> Well, thank you Ned, for the most courteous and gracious reply. I
> was glad to post the information that you requested.
Huh? You did? That has nothing to do with explaining this stuff:
> the nonlinear
> autoregressive moving average with exogenous inputs (NARMAX) technique
> for non-linear CAE design and analysis of magnetic audio transformer
> products? Or since the evolution of both SISO and MIMO forms to the
> multistructural input-output NARMAX solution space occured so long
> ago, has Magnequest adopted more competitive techniques, such as Neuro
> hyperbolic tangent-sigmoid type activation functions and
> Levenberg-Marquardt training optimization algorithms?
It's a rehash of the Atwood paper (which isn't anything new),
and a couple of web pages, one of which doesn't even list
audio transformers as an application for their products.
(The other doesn't have a DNS entry, I guess you misspelt it)
> The objective and intelligent
> manner in which you handle matters of transformer design and analysis,
> as demonstrated above, illustrates that most conclusively.
I can't see that you've handled much of any "matters of transformer design
& analysis" at all, and certainly not objectively, you just
reposted someone else's analysis, and added your opinions.
Nothing in the vein of *you* discussing the points you brought up,
or how they apply to the transformers Mr. Atwood analyzed or
the ones you own.
You don't even grasp the difference between an electric
guitar and an electric guitar amplifier (which is a considerably
more complex subject than you give it credit for).I'd guess that people
who cannot make the distinction are probably just cutting & pasting
stuff like " the nonlinear autoregressive moving average with exogenous
inputs (NARMAX) technique for non-linear CAE design" into their posts.
I haven't seen any evidence that you understand it.
And
> additionally, is quite an incentive for hobbyist to purchase fine
> Magnequest transformer products directly from you,
Heck, I was hardly selling any until you and Jute decided to make
Magnequest the main theme of discussion here. I'd assume
the readers are doing web searches and reading the glowing reviews
of products that use Magnequest transformers.
as your
> advanced interpersonal skills
At least I've got some.
and open-minded objectivity are so readily
> apparent.
Well, I'd be doing a lot worse if I was using you
for a role model.
--
Ned Carlson Triode Electronics "where da tubes are!"
2225 W Roscoe Chicago, IL, 60618 USA
ph 773-871-7459 fax 773-871-7938
12:30 to 8 PM CT, (1830-0200 UTC) 12:30-5 Sat, Closed Wed & Sun
<A HREF="http://www.triodeel.com">http://www.triodeel.com</A>
Sander deWaal
>I find it a bit strange when you ask the hobbyist and designers to
>advise YOU, the manufacturer. You are taking the profits, you are
>supposed to know. At least, that's the way it has worked with all the
>other electronic manufacturers I have worked with during my carrer as a
>designer and researcher in the electronics industry.
That's *exactly* what I did when I asked this old
tranny winder to wind some for me.
If you want optimum results, this is the only way
to go, instead of buying stock items.
--
Sander deWaal
c...@wxs.nl
lon...@my-deja.com
> >My larger point was that there really isn't a lot of quote "new"
> >"contemporary"
> >core materials out there. Your post also seems to say about the same
thing.
Isn't mu metal just permalloy? Anyone know for sure?
> Anything that has to do with exotic magnetic core materials is
interesting
> stuff, IMHO, especially if it can be applied to audio.
good stuff snipped, sorry
> Dr. Harold Arnold was the first director of Bell Telephone
Laboratories.
> Permalloy was first patented in 1917, having been developed by Gustav
Elman at
> Bell Labs beginning in 1906. Elman was actually the person who led
the
> investigation of high-permeability nickel-iron alloys there.
>
> John
John, Mike, et al,
These following several magnetics papers will be included in the rat
collected tube papers volume 1. There is a vast amount of magnetics
research out there among the early journals. Work on the properties
of iron and nickel was conducted way back into the 1800's. It wasn't
my intention to have a great concentration of magnetics papers in
vol. 1, because of space restrictions. However, if you guys can
identify seminal works for me, I'll see what I can do.
Arnold was a gifted visionary. He did the staff recruiting as part
of building his world class laboratory. For example, he also
recruited van der Bijl to research and design tubes for AT&T. The
resulting Western Electric tubes are legendary. Whatever direction
Arnold chose to take Bell Labs in, astonishing breakthroughs were
possible. Bell Labs did pioneering work in noise (Johnson and
Nyquist), information theory (Shannon), semiconductors (Shockley
Brattain and Bardeen), gridded tubes (Arnold and van der Bijl),
microwave tubes (Pierce), the list goes on. While tinkering with
an early microwave communications experiment, Penzias at Bell Labs
couldn't account for 3 dB of noise in his link. Turns out that he
had just discovered the residual noise from the big bang. Some
people consider this the most important scientific discovery of this
century. All in a days work for Bell Labs.
Arnold, H. D., and Elmen, G. W., "Permalloy, A New Magnetic Material
of Very High Permeability," Bell Syst. Tech. Jour., Vol. 2, No. 2,
pp. 101-111, July 1923. Landmark paper, discovery will have a profound
effect on electrical communication. With proper heat treatment,
material has a permeability as high as 90,000, about 200 times higher
than the best iron for low magnetic fields. Heat treatment and carbon
content are critical. There is a companion paper on the
crystallography, see McKeehan 1923.
Bozorth, R. M., "The Present Status of Ferromagnetic Theory," Bell
System Technical Journal, vol. 15, pp. 63-91, 1936.
McKeehan, L. W., "The Crystal Structure of Iron Nickel Alloys," Phyical
Reviews 2, 21, 1923. Deals with the specific properties of permalloy.
Companion paper to Arnold 1923.
Wrathall, E. T., "Audio Frequency Transformers," The Wireless Engineer,
part 1, pp. 293-298, June 1937.
part 2, pp. 363-369, July 1937.
part 3, pp. 414-421, August 1937.
An excellent engineering review. From the first paragraph:
"The object of this article is to review the principles of audio
frequency transformers, to apply these principles to simple and
practical methods of design, and finally to describe the essential
tests which should be applied to a finished transformer."
respects
gary
JLSEM
>Isn't mu metal just permalloy? Anyone know for sure?
Mumetal is similar to 78% Permalloy, but has 4.8% copper and 1.5% chromium (for
increased electrical resistivity) added. the significant difference is Mumetal
has higher permeability in extremely small fields which makes it useful for
shielding.
>Arnold was a gifted visionary. He did the staff recruiting as part
>of building his world class laboratory. For example, he also
>recruited van der Bijl to research and design tubes for AT&T. The
>resulting Western Electric tubes are legendary. Whatever direction
>Arnold chose to take Bell Labs in, astonishing breakthroughs were
>possible. Bell Labs did pioneering work in noise (Johnson and
>Nyquist), information theory (Shannon), semiconductors (Shockley
>Brattain and Bardeen), gridded tubes (Arnold and van der Bijl),
>microwave tubes (Pierce), the list goes on. While tinkering with
>an early microwave communications experiment, Penzias at Bell Labs
>couldn't account for 3 dB of noise in his link. Turns out that he
>had just discovered the residual noise from the big bang. Some
>people consider this the most important scientific discovery of this
>century. All in a days work for Bell Labs.
>
The depression took a terrible toll on the great commercial laboratories of the
era (Westinghouse, General Electric, and Bell) with many lay-offs and
restricted budgets. Arnold was gone from Bell by the thirties and I am only
speculating that he started Arnold Engineering since its formation coincides
chronologically with his departure from Bell Labs. Does anyone know for sure;
it can't be just coincidence? Poor Gustav Elmen was spent by the pressures of
the times and was said to have whiled away his last years at Bell mostly
smoking his pipe and staring out the window, mentally exhausted.
John
JLSEM
> Poor Gustav Elmen was spent by the pressures of
>the times and was said to have whiled away his last years at Bell mostly
>smoking his pipe and staring out the window, mentally exhausted.
>
>
I need to correct this statement I posted earlier. Elmen smoked cigars, not a
pipe.
>>Arnold was a gifted visionary. He did the staff recruiting as part
>>of building his world class laboratory.
Marvin Kelly, who took over direction of the lab in the 'thirties, began the
recruitment of physisists proficient in quantum mechanics theory, ushering in
the modern era of Bell Laboratories' achievements. For us tubeheads, the
'thirties were a marvelous decade; most of the great stuff we all know and love
came from the corporate research labs of the great American companies (as well
as foreign ones) of that era.
John
Cutts the Butcher
: Just ask the fella from DC who came for a visit
: last week or so.
Are there a bunch of DIYers in the DC area? Would there be interest in
some kind of a DIY club, meeting once every so often, to look at projects,
construction, etc.?
--
Vandit Kalia GO FLYERS!!!!!
-------------------------------------------------------------------------
Salut to the memory of Dmitri Tertyshny, #5.
Acrosound
With a host of different brand names in the marketplace for various of the
nickel alloy electrical grade laminations it is difficult to track the
discussions.
Principally (at the current time) there are two "families" of nickel alloys in
production that are suitable for selected audio transformer applications. let
us call them "high" and "low" nickels.
Companies who make the "low" nickels may make it in a 45% or 47% or 49%.
the "high" nickels come in the range generally btwn 75 to 80 percent nickel.
And there is a lot of confusion in the marketplace about the nickels. I have
had people ask " Is your permalloy trans 100% nickel" and act very confused
when I tell them that (to my knowledge) none of the nickel lams are 100%
nickel.
Then I will generally go on and tell them that "permalloy" is (or was) a
specific brand name for a nickel alloy produced by Western Electric. Other
names might by mu-metal and hy-mu... these too being particular brand names.
One of the larger (I think actually the largest... but) producers of nickel
alloy electrical grade sheet is Carpenter Steel out of good ole Reading PA.
Their brand name for "high" nickel is HyMu 80.
Mu-metal as a brand name, IIRC, is used by (and I assume owned by) Magnetic
Metals out of Camden NJ. Mag Metals at least by scuttlebutt I've heard
throughout the industry is the largest "convertor" of mu metal for the
transformer industry in the world.
Ironically, again, from info gleaned through informal industry sources.. the
largest use of "high" nickel in today's marketplace is for modem transformers
and for GFI circuits...
which leads me to another distinction in nickel lams... it is the shape of the
loop. Nickel lams (at least through some vendors) can be bought in either a
round loop or a square loop configuration. The "round" loop is generally
specified for audio tranneys. the "square loop" is spec'd for applications
where a "trigger" is sought or where a very definite saturation point is much
more evident and needed electrically. Hope I got this all right.
here is the composition of the Carpenter Hy_mu 80 material.
carbon 0.02%
manganese 0.50%
silicon 0.35%
nickel 80.00%
molybdenum 4.20%
iron BALANCE
one other note... perhaps I can get back to it at a later point... Carpenter
makes different grades of even the "high" nickels and manufactures a grade that
is even moreso optimized for use in magnetic shielding applications. The
mechnanical properties are optimized for "fabricating" purposes.
Carpenter Steel has a great booklet called
Soft Magnetic Alloys
High Permeability aloys
Magnetic Core Irons
it is (or at least was) available free from their customer service department
in Reading PA.
gotta go,
MSL
Alan Douglas
>Arnold was gone from Bell by the thirties and I am only
>speculating that he started Arnold Engineering since its formation coincides
>chronologically with his departure from Bell Labs. Does anyone know for sure;
>it can't be just coincidence?
Harold De Forest Arnold departed Bell Labs when he died of a heart
attack on July 10, 1933. according to the IRE Proceedings for August
p. 1068.
In the 1950 IRE Yearbook, and perhaps elsewhere but I haven't
looked, Robert M. Arnold of Chicago is listed as president of Arnold
Engineering.
73, Alan
Paul Gustafson
I would gladly purchase Magnequest products from Ned. If Mike would give
me a pair of his Dynaco replacements to try in my st70 I would be
eternally grateful as well. If they arrived with a bent mounting tab I
would straighten it, like any other regular person would. If they
arrived with the end-bell bolts loose I would tighten them, like any
other regular person would. If they arrived with a bee in the box I
would kill it, dip it in chocolate and eat it, they are a delicacy in
some parts of the world you know. And I would do these things without a
public hissy-fit because it's just sour grapes when guys like you need
to feed your egos by making other people angry and combatant. It's
classic psycology 101 kind of behavior. The trouble is we all can see it
and you probably can't because your mind is so clouded by anger, for
whatever reason. Were you picked on in school by the cool kids??
Chill out and be at peace with yourself, if you can. Go build an amp,
it's good therapy.
Paul G
(not part of the "mob", just a regular reader here, with no beef with
anyone, except those who seem to want/need the attention.)
dange...@my-deja.com wrote:
>
> In article <UfQo3.17992$x7.7...@newscene.newscene.com>,
> postm...@triodeel.com wrote:
> > On Sat, 31 Jul 1999 21:23:11 GMT , dang...@earthlink.net wrote:
> > > ANALYSIS OF 80+ TUBE AUDIO OUTPUT TRANSFORMERS
> > > Study performed by John Atwood, MSEE
> >
> > What a complete and utter load of crap.
> > Thank God you unloaded this *here*, on AGA you'd
> > be torn to pieces. Of course, you don't have the guts to
> > post on AGA or RAP, they'd eat you alive.
> > Dave,I don't hate you. Please, get some help, now.
> >
> > Check out our upgrade boards for Dynaco (TM) ST70, Mk2 & Mk3...
> > http://www.triodeel.com/dynaco.html
> >
> > Ned Carlson Triode Electronics "where da tubes are!"
> > 2225 W Roscoe Chicago, IL, 60618 USA http://www.triodeel.com
> > ph 773-871-7459 fax 773-871-7938
> > 12:30 to 8 PM CT, (1830-0200 UTC) 12:30-5 Sat, Closed Wed & Sun
> >
>
> Well, thank you Ned, for the most courteous and gracious reply. I
> was glad to post the information that you requested.
>
> And it's good to be proven wrong by posts like your own. Clearly, the
> small Magnequest Mob attempting to dominate RAT, often referred to as
> underemployed electric guitar repair technicians, flamers, spamers,
> and the like, is nothing but fiction. The objective and intelligent
> manner in which you handle matters of transformer design and analysis,
> as demonstrated above, illustrates that most conclusively. And
> additionally, is quite an incentive for hobbyist to purchase fine
> Magnequest transformer products directly from you, as your
> advanced interpersonal skills and open-minded objectivity are so readily
> apparent.
>
> Regards,
> Dangerdave
Gerald Stombaugh
Mike:
you are absolutely correct. National Arnold has made
wound silicon coils for many years. A very fine company
but a different Arnold.
Their website is namcores.com
Gerald Stombaugh
Acrosound
>>Heck, I was hardly selling any until you and Jute decided to make
Magnequest the main theme of discussion here. I'd assume
the readers are doing web searches and reading the glowing reviews
of products that use Magnequest transformers.<<
Ned:
Make that another excellent rave review for an amplifier using our tranneys.
In today's mail I received the new issue of Listener magazine and in it was a
full fledged killer review of the FI "X" amp (SE 2A3) using our TFA 204 single
ended output transformer.
Kudos to Don Garber on a job well done.
MSL
JLSEM
>attack on July 10, 1933. according to the IRE Proceedings for August
>p. 1068.
>
> In the 1950 IRE Yearbook, and perhaps elsewhere but I haven't
>looked, Robert M. Arnold of Chicago is listed as president of Arnold
>Engineering.
>
>73, Alan
Alan,
Thanks for the info. I have been curious about that for some time and I am
glad you have set the record straight. I can only guess that the stress from
the hard times at Bell labs contributed to Arnold's demise.
John
dange...@my-deja.com
anti-Magnequest posts, and so on, Paul.
I don't care about bees or tabs.
I've already stated what I care about.
For the sake of integrity, please direct your replies to the original
posters' comments alone.
Thank You.
lon...@my-deja.com
> While tinkering with
> an early microwave communications experiment, Penzias at Bell Labs
> couldn't account for 3 dB of noise in his link. Turns out that he
> had just discovered the residual noise from the big bang. Some
> people consider this the most important scientific discovery of this
> century. All in a days work for Bell Labs.
Let me change the story on this a little and get some facts straight.
It was Wilson and Penzias at Bell Labs. They were both working as
radioastronomers, Bell Labs thought it would be good to have
radioastronomers on the staff. The microwave horn they used was left
over from the development of the Telstar program, the first
communications satellite. Wilson and Penzias had to discard most of
the Telstar communications electronics because it was too noisy and
insensitive for radioastronomy. They built their own electronics,
including a helium cooled reference source.
As they brought their system to life they soon realized that something
was wrong. There were three degrees K of extra noise that they
could not account for. (Not 3 dB, radioastronomers work in noise
temperature, hence the 3 deg K above zero). They spent a year
checking their calculations and going over the equipment. They
scrubbed the horn clean of its white pigeon dielectric. They sealed
horn seams with aluminum tape. In consulting with other physicists
about their problem, they encountered a young Princeton theorist,
Peebles, who had argued that there ought to be a background of radio
noise left over from the big bang. The resulting collaboration was
historic.
There is a book about the Bell Labs. "Three Degrees Above Zero."
Jeremy Bernstein, Scribners, 1984, isbn 0-684-18170-3
gary out
Paul Gustafson
I used to run one of those big paper cutters. It was like a huge
guillotine driven by a gear reduced flywheel about 8 feet in diameter!
This thing would cut a 4 by 4 like it was a toothpick. Man what a scary
thing. It fortunately had a safety where you had to use two hands to
operate it. Good thing... The place I work at now has a couple of
winding machines and tons of raw material, wire and cores and such. I
was thinking about trying my luck at a choke, then get brave and try a
tranny. Would you be interested in providing me with any helpful info?
Like the gauges and # of turns and interleaving of a nice 60 watt output
tranny, or maybe a 800 vct power tranny with a bias winding and center
tapped filament windings? You could take it off line if you desire, send
it to my email addr. I promise I will never disclose the info, nor will
I use it for commercial purposes. I just want to give it a try, I love a
challenge.
Take it easy and stay cool,
Paul G
Acrosound wrote:
>
> Acrosound (acro...@aol.com) wrote:
>
> : Am I wasting my breath with this guy???
>
> to which Kurt Strain replied:
>
> >>Yes. But the rest of us are getting better educated by you in terms of the
> transformer industry.<<
>
> When possible I try to give informative helpful responses to questions. And I
> do love tranneys, materials (almost to a point of being a materials junkie),
> winding machines, big old one ton cast iron fully manual paper cutters... and
> showing off all of this stuff. Just ask the fella from DC who came for a visit
> last week or so.
>
Bruce Normann
Bruce in Washinggton DC
In article <7o7d3i$i...@netaxs.com>, vka...@netaxs.com says...
Grover Gardner
> Are there a bunch of DIYers in the DC area? Would there be interest in
> some kind of a DIY club, meeting once every so often, to look at projects,
> construction, etc.?
Sure, I'd love to. Throw out some dates and times! :-)
--
Grover Gardner
gro...@postoffice.att.net
lon...@my-deja.com
> Are there a bunch of DIYers in the DC area? Would there be interest
> in some kind of a DIY club, meeting once every so often, to look at
> projects, construction, etc.?
>
> --
> Vandit Kalia
Yes, I'm in DC too, so count me in. How about
sometime after the weather breaks a bit, and the
tourists have left town? Some show and tell sounds
like fun, and so does some good listening.
gary
"those who fail to remember history are ... um
Roderick Spode
sometime during the course of this week and we can start scheduling
things.
Cheers,
Vandit
Pete G.
from the back shouts a voice "count me in too".
--
Pete G.
** Remove the first "p" in my E-Mail address if you wish to send E-Mail to me.**
Grover Gardner
contact me off-list?
--
Grover Gardner
gro...@postoffice.att.net