MAVEN PEAL ZEETA...EYEBALL REPORT
Lord Valve
I finally found time to sit down with Dave Zimmerman's
Maven Peal "Zeeta" amp today. Most of the regulars
here know Dave as the designer of the Maven Peal
Sag Circuit, a sandy little number that emulates
rectifier tube sag (and then some) as well as provides
power scaling for the output stage of a tube amp. An
interesting side effect is that it makes for a *totally*
hum-free DC supply. (I consider this to be more useful
than the "sag" feature, but WTF do *I* know...I'm an
organist. ;-) This article is going to deal mainly
with the construction, circuitry, and physical appearance
of the amp, rather than the tone and playability. I'll
do a post on how it sounds later, when I can get opinions
from five or six local guitar pickers, one of whom is my
assistant technician. (Scooter Barnes, who, as soon as
he figures out he ain't gettin' paid by the note, will be
one of the finest pickers on the planet.)
FIRST IMPRESSIONS
The Zeeta comes with its own high-quality roadcase;
it was delivered (upside-down, I might add...you'd
figure the fact that the handles will kill the shit
outta your hands in this position mighta given the
delivery driver *some* kind of a clue) by FedEx
in early December. I was swamped with the usual
Christmas retail crap, so, after we played it for
5 minutes to make sure it wasn't DOA, we just put
it back into the case and let it rot until today.
When we gave it the initial checkout, we discovered
that the mike input was *way* noisy...probably a
bad tube, I thought. I called Dave up and gave
him the low-down, and he said he was sending us
an upgraded mil-spec ceramic-body IC to install
in place of the consumer-grade part that was
currently in the power supply. (He knew I was
going to take his baby apart and lick all the pieces,
so why not upgrade...right?) At any rate, the Zeeta
impressed us (me and Scooter and Lady Valve) as a
really solid-looking piece of gear. Pretty, too.
THE CABINET
Absolutely gorgeous. You don't see joinery like this
every day. The wood is cabinet-grade clear pine; the
cabinet is covered with a lightly textured maroon Tolex.
One thing I noticed about the amp right away was the
care with which the Tolex was applied...it looked like
it was done by someone who was not only really damn
good at it, but enjoyed the hell out of doing it. (This
was confirmed in a call I made to Dave tonight...he said
the dude who does the covering only does Ferraris and
Lotuses. And the Zeeta, evidently.) All the joints on
the Tolex are dead solid perfect. Better than anything
I've seen before by an order of magnitude. Really. The
box itself is radiused throughout; the back panels are
*thick* wood...5/8" at least, radiused, and and even
the ends (which you cannot see without removing the
backs) are Tolexed perfectly. Never seen anything like
it. All the fasteners are stainless steel. Speaking of
stainless steel, the chassis straps on top of the amp
(like a Fender has) are machined from solid stainless
steel, 3/16" thick. An inch wide, they weigh nearly a
POUND each! The chassis bolts are Phillips-drive stainless
1/4-20; if this amp falls on its face, they are *not*
going to bend, period. The grille cloth is maroon also,
with tasty white piping around the edge. The handle is a
black English leather type from Penn Fabrication referred
to as a "dog-bone". On the bottom are a set of *huge* rubber
feet. Regulation Fender-type corners, two-legged with
turned-in lips. The corners appear to be the only hardware
on the amp that's not custom built. The speaker is a blue-
basket Celestion Alnico 12" "bulldog" type. It's hooked to
the amp with a piece of 12-gauge audiowanker OFC speaker
cable (why not?) that has been covered with a piece of
sky-blue heatshrink. The plug is an old-fashioned squarish
Switchcraft plastic-backed right-angle type; I'd have preferred
to see the more modern (and considerably more rugged) part #228
from the same company. The inside of the top part of the cabinet
is covered with overlapping strips of copper shielding tape
which, according to Dave, are stuck to each other (and to the
cabinet) with conductive adhesive. The shielding goes down the
sides of the cabinet as well as covering the inside of the top;
this is because the chassis, which is bent from a single piece
metal, is open at the ends.
UNDER THE HOOD
I took the chassis out; no surprises, it slid right out without
binding on anything. I couldn't believe what I was looking at.
The damn thing is *literally* built like a tank. The chassis
is bent from a single piece of *very* stout aluminum...a full
*eighth* of an inch thick! It makes a BF Fender chassis look
like tin-foil. I could just barely flex it, and I had to strain
like hell to produce even the slight flex I was able to achieve.
(I ain't exactly small, and I *do* eat my Wheaties.) The control
surface is slanted like a BF Fender...my favorite design. Looks
cool, and makes the controls easy to see and adjust. It's black
(anodized, I suppose, although I really didn't look at the finish
that closely) with white lettering. Black chicken-heads on the
pots. Two inputs, one for a mike and one for an instrument.
Power switch, standby switch, and a Fender-type red pilot light.
The circuit is nearly identical to a Tweed Deluxe. (With the
exception of the power supply, of course.) Mike vol, Instrument
vol, Tone, Sag, and Power are the controls. The "sag" control
lets you dial in the amount of power-supply sag you like, while
the "power" control lets you adjust the actual output power of
the amp between one and fifteen watts. Inside the chassis was
the single best set of parts I have ever seen, period. Central
to and dominating the audio-circuitry layout is the cathode
bypass cap for the output tubes. (2 X JJ/Tesla EL-84.) It's
a *monsterous* 270uF/250V poly cap, the size of a soup can. A
little larger than a soup can, in fact. The bypass caps for the
preamp are huge, too...24uF/250V, same type, from the same French
manufacturer. The coupling and tone caps are all audiowanker
types. The preamp plate load resistors are three-watt metal
composition parts. Are you starting to get the impression that
the Zeeta is overbuilt? Read on... The audio portion of the
Zeeta is all handwired, point-to-point. The resistors and caps
and whatnot are mounted on a custom-built L-shaped turret board,
made of mil-spec fiberglass an eighth of an inch thick. Numerous
support points are provided for this board, to keep it stiff.
Every bolt or machine screw that needs a nut on it has an
aircraft-style nylon insert vibration-proof type installed. The
power tranny is a large toroid type, mechanically isolated from
the chassis to reduce mechanical hum. The OPT is mounted on 1/4"
standoffs; I asked Dave about this, since I wasn't sure what good
that would do (if any) and the answer was "Because it looks cool."
It does, in fact, look cool. Jacks are the ReAn or Cliff's nylon
type, with gold-plated contacts. The audio pots are from CTS,
while the Sag and Power controls are Clarostat RV-4 conductive
plastic types. All the internal wiring (with the exception of
the transformer leads and the shielded cables that go to the first
preamp tube) is Teflon-insulated sliverplated OFC. Good stuff;
my own personal favorite, in fact. (Sorry, I think cloth-covered
wire is crap. Sue me.) Tube sockets are ceramic. The two 12AX7
preamp tubes are the LP variety from Sovtek; Dave and I discussed
trying the new EH variety (no, they are *not* the same thing as
the LPS, although they were for awhile...see my description of
the new 12AX7EH on another thread) when my batch of 250 shows
up and I get done tossing out the clunkers. The Zeeta runs DC
heaters, even for the power tubes. Well-regulated, too. The
power tubes have their filaments wired in series (the DC filament
supply is 12.6 volts) so that if one dies, the other shuts off
too. A word about the soldering in this particualr unit...it
was crummy. I reamed Dave about this on the phone; he told
me that chassis was a prototype, wired by someone who no longer
works for him, and modified and updated multiple times. (The
serial number is 0010.) I found the tip shunt ground wire on
the mike input jack was not soldered at all, and I also redid
some of the connections on the tube sockets. (One nice thing
about Teflon wire is that you can resolder it a jillion times
and it still looks brand new.) I also had to re-solder and
re-dress the shielded leads to the #1 preamp socket, as they
were done completely wrong. (Whoever did 'em neglected to
remove the conductive plastic electrostatic shielding from
the center conductors, causing several high-impedance shorts
both on the socket and under the turret board at their other
ends.) Dave assures me that the currently-produced Zeetas
are much neater inside. I should hope so. On to the power
supply...LOTS of sand here, all over the place. Mosfets,
ICs, regulators, you know...SAND. All topnotch, too. The
Molex connectors used for the various inputs/outputs to and
from the board were of a type I haven't seen before...special
high-voltage connectors, which are insulated all the way to
the bottom of each individual pin. Tight-fitting, too...
three or four cuts above the cheapshit ones you see inside
most MI gear. If I ever get around to building some of my
amps, I'm gonna use those for sure. The power board is a
conventional SS-type PCB, also very thick (but not as thick
as the turret board in the preamp) mil-spec fiberglass,
double-sided and plated-through-hole. I can't comment on
how it works, because I don't know. (No schematic...Dave?)
Dave's patents are somewhere online, I think.
Once I was done eyeballing all the guts, I gave the chassis
my Hammer Test. I take a 2-pound Stanley shot-filled Deadblow
hammer and whack the crap out of 'em; if anything is rattly,
it's gonna show up when I do this. I couldn't believe it...
it was like whacking a piece of concrete. No rattle at all...
nothing. Nil point zippity-shit. The only thing I could hear
on first whack was the cage nuts rattling in their clips; I put
bolts in them and tightened them all the way down (like they
would be when the chassis was in the cabinet) and after that
it was like whacking a piece of lead. The Zeeta is the single
most rattle-free combo amp I have ever encountered. (Contrast
this with, say, the Mesa Heartbreaker, which rattles like a
beer can fulla buckshot.) All combo amps should be built like
this, and would, if it wasn't for...
SHOW ME DA MONEY!
Egad, FOUR GRAND! That's a *lotta* scratch. I know why it's
so much, though, after eyeballing the parts. The output stage
cathode bypass cap costs a hundred bucks by itself. OUCH!
There are a lot of hand-machined parts in the Zeeta; some of
them wouldn't be much cheaper even in production quantities.
The amp does come with a top-quality roadcase, too. (I've had
cases like that made for some of my customers, and they run in
the $500-$600 range.) Once I figured out the approximate cost
of all the stuff that goes into a Zeeta, it was apparent that
Mr. Zimmerman ain't gettin' rich off em, at least, not in a
hurry. This amp is a Rolls Royce, and there are certainly
people who will pay for this type of construction. (Neil
Young bought one, for instance.) I can't wait to hear some
smokin' guitarists put it through its paces...stay tuned.
Dr. Nuketopia gets this amp next; we'll see if his take on
it mirrors mine. Mine is: it's the best-built guitar amp
I've ever seen...and rumor has it that I've seen more than
a few. ;-)
Lord Valve
VISIT MY WEBSITE: http://www.nebsnow.com/LordValve
I specialize in top quality HAND SELECTED NOS and
current-production vacuum tubes for guitar and
bass amps. Good prices, fast service.
NBS Electronics, 230 South Broadway, Denver, CO 80209-1510
Phone orders/tech support after 1:30 PM Denver time at 303-778-1156
VISA - MASTERCARD
"Far better it is to dare mighty things--than to take
rank with those poor, timid spirits who know neither
victory or defeat."
-Theodore Roosevelt-
Zekmoe
>From: Lord Valve
> Whole review clipped to save space<
Great review! It's nice to hear about quality built products, where he final
cost takes a back seat to quality of the finished product. Hope to hear one
soon.
Bob Maggio
Not a downstroke, fistpicker.
www.curbdog.org
Duncan Munro
<detr...@ix.netcom.com> wrote:
> Central
>to and dominating the audio-circuitry layout is the cathode
>bypass cap for the output tubes. (2 X JJ/Tesla EL-84.) It's
>a *monsterous* 270uF/250V poly cap, the size of a soup can.
Wow! A poly cap for cathode bypass?
Nice review, you obviously spent a great deal of time pawing over it
(and sounds like you enjoyed doing so).
--
Duncan Munro BOF #23
http://www.duncanamps.com
Danny Russell
Lord Valve wrote:
>
> The OPT is mounted on 1/4"
> standoffs; I asked Dave about this, since I wasn't sure what good
> that would do (if any) and the answer was "Because it looks cool."
I'd like to think I'm a pretty good judge of character, and I'm always
skeptical of dry, souless, science completely abscent of any artform
whatsoever. This above line to me was the most telling of the whole
review. "Because it looks cool"!. How could you not like the guy
after reading that? -Danny
--
<<<GET BLITZED!!!>>>
http://home.flash.net/~blitz/tunes.html
AMD450- MIDI- MIC-&-BALLS!
Miles O'Neal
> I'd like to think I'm a pretty good judge of character, and I'm always
> skeptical of dry, souless, science completely abscent of any artform
> whatsoever. This above line to me was the most telling of the whole
> review. "Because it looks cool"!. How could you not like the guy
> after reading that? -Danny
Not only that, but honest as all get out. Too many
people in today's world would have come up with a
pseudo-scientific BS marketing reason.
``It decouples the ouput transformer lack of
vibration from the power transformer's corresponding
lack of vibration induced by the power transformer's
mechanical standoffs. In addition, it lowers the
electromagnetic interference coefficient ratio between
the output transformer's core laminations and the inherent
quantum eddy currents in the chassis by 3 millirheams.''
But hey - the guy has always been a straight shooter in
AGA.
-Miles
Miles O'Neal
worth that much? Even if it will stand up to
anything short of a direct nuclear strike,
including the USPS and UPS.
Just go practice some more.
8^P
BK
> ``It decouples the ouput transformer lack of
> vibration from the power transformer's corresponding
> lack of vibration induced by the power transformer's
> mechanical standoffs. In addition, it lowers the
> electromagnetic interference coefficient ratio between
> the output transformer's core laminations and the inherent
> quantum eddy currents in the chassis by 3 millirheams.''
Nahh, that's caused by those fibrous bell washers....hehehehehehe
;-)
Bill
Lord Valve
aluminum. It is, in fact, 1/8" steel. (Don't know why
I didn't give it the magnet test in the first place when I
found out I couldn't bend it.) Sorry for the error.
LV
Mike Schway
<detr...@ix.netcom.com> wrote:
Yikes! So how much does the whole thing weigh?
--------------------------------------------------------------------
Mike Schway | [Picture your favorite quote here]
msc...@nas.com |
--------------------------------------------------------------------
Lord Valve
the road case.
LV
Simply Steve
Ye should be thoroughly cudgelled!
Lady Valve, muster the shillelaghs!
Shellback Steve
Mike Schway
<detr...@ix.netcom.com> wrote:
>49 pounds, including the removable linecord, not including
>the road case.
>LV
Jeez Louise! That's over 3-1/4 lbs per watt! A Jensen-equiped BF Twin
is only 1 lb/W. P'haps a SF Champ is a *bit* heavier than the Zeeta by
that standard, but this is one hefty sonnafabitch.
Kent Pearson
craftsmanship that goes above and beyond what one can expect, even from a
quality amp.
I should say though, that for $4K I certainly wouldn't expect any less -
especially in the wattage department. Quite truthfully, 15 watts is what I
use for my woodshedding at home alone. I personally could never gig with
that kind of power, not the kind of music I generally play - so for me it
would be a four thousand dollar amp for woodshedding only. Hmmm.... I
wonder what a 50 or 100 watt version (something I could use) of the same
(or a head) would run, if it were offered??
But again, I'm glad to hear that the build quality is well above average (or
better). I'm waiting to hear the reports on the sound. It should be pretty
good, from all indications. I guess it'd HAVE to be pretty amazing, for
four thousand scrod!
- KP
Cindy Berg
Lord Valve wrote:
> Lord Valve Speaketh:
> ... I can't comment on
> how it works, because I don't know. (No schematic...Dave?)
> Dave's patents are somewhere online, I think.
For anyone interested, David's patent "Variable control of Electronic
power supplies" can be found at:
http://www.delphion.com/details?pn=US05909145__
Interesting reading.
Bob
>Lord Valve Speaketh:
>
>I finally found time to sit down with Dave Zimmerman's
>Maven Peal "Zeeta" amp today.
)snip(
>too. A word about the soldering in this particualr unit...it
>was crummy. I reamed Dave about this on the phone; he told
>me that chassis was a prototype, wired by someone who no longer
>works for him, and modified and updated multiple times. (The
>serial number is 0010.) I found the tip shunt ground wire on
>the mike input jack was not soldered at all, and I also redid
>some of the connections on the tube sockets. (One nice thing
>about Teflon wire is that you can resolder it a jillion times
>and it still looks brand new.) I also had to re-solder and
>re-dress the shielded leads to the #1 preamp socket, as they
>were done completely wrong. (Whoever did 'em neglected to
>remove the conductive plastic electrostatic shielding from
>the center conductors, causing several high-impedance shorts
>both on the socket and under the turret board at their other
>ends.)
)snip(
> Mine is: it's the best-built guitar amp
>I've ever seen...and rumor has it that I've seen more than
>a few. ;-)
>
>Lord Valve
Strange review - the best built amp you've ever seen is improperly
built??
You'd think for $US4K they might inspect it... especially sending it
out for review... or worse.... maybe they did....
Bcoolstuff
review... >>
For four grand he should clean your house and walk the dog for a month
straight. I think I'll go find some more Traynors.
Billy
Maven Peal Instruments, Inc.
> (Neil Young bought one, for instance.)
The Zeeta is based on the tweed Deluxe partly because that's the amp Mr.
Young uses. I have since added a push-pull feature (present, but not
labeled, on the amp Lord Valve has) to the tone knob--push it in for a
tweed Super power amp, pull it out for a Deluxe power amp.
I am going to *give* Mr. Young a Zeeta with no strings attached simply
because he is one of my all time favorite guitar players, and it floats
my boat to think that he may be playing an amp that I made. I am not
asking for any kind of endorsement at all, and don't expect one. In
fact, after enjoying the anti-big business flavor of "This Note's for
You" for many years, I would be disappointed if Mr. Young broke the
code... even for Maven Peal.
Lord Valve, thank you for taking the time to review the Zeeta during
your busy season, and for your knowledgeable advice. I am honored to
have such a review written by such an opinionated old coonhound.
When Lord Valve is done with the amp, we are going to send it to Dr.
Nuketopia. After that, I hope that Scott Colborn will be available to
look at it.
David Zimmerman
Maven Peal Instruments, Inc.
http:\\www.mavenpeal.com
Maven Peal Instruments, Inc.
> Hmmm.... I
> wonder what a 50 or 100 watt version (something I could use) of the same
> (or a head) would run, if it were offered??
The Maven Peal Ganesh is a 50 watt plexi-based head. $3650 includes a flight
case and shipping, along with Sag and Wattage controls. This model also
features two new knobs, Sag Rate and Recovery Rate.
David Zimmerman
www.mavenpeal.com
Lord Valve
the right place. Of course, some folks might not
eat their Wheaties. SS for them, their tone can
reek.
LV
Lord Valve
when it was time to write the review.
LV
Lord Valve
Bob wrote:
I didn't say it was improperly built, I said it had
a bit of sloppy wiring. Perhaps you don't have a
lot of experience with prototypes; they tend
to get pretty hacky-looking inside what with
all the mods and updates and upgrades
done to 'em. If I was going to write a puff piece
(not my style; I don't shit anyone) I'd never
have mentioned it. Production units will
ceretainly be 100% perfect...Dave is a
fuckin' FANATIC on quality. And BTW...
I didn't just sit around and whine about the
sloppy wiring...I corrected it.
LV
Cybermonk
attenuation of some sort, rather than low-power-only amps. The goal is to
only have to buy 1 amp, not 4, that produces power-tube saturation in the
home studio, cafe, club, or concert hall. So I recently focused on
gathering info/links for "variable-SPL amps" or selectable-wattage amps,
rather than "low-wattage" (fixed wattage) amps.
http://www.amptone.com/#varwatt
"Maven Peal Instruments, Inc." <ma...@peal.net> wrote in message
news:3A5D5F64...@peal.net...
hawkeye in exile
> 8^P
has Miles broken into Jack Zucker's account?
kraving a Komet,
j
--------------------------------------------------------------------------
R. J. "jeff" Sanders Santa Clara, CA
"Let everybody get together then and we'll try to make it." - Howling Wolf
E-mail s a n d e r s @ n e t c o m . c o m (exp. 12/31/01)
Bob
OK you should have specified it was a prototype and was 're-worked' a
lot - but then - why mention all the re-working if that was the case?
It's too bad you couldn't test a standard production amp though.
But anyway - do you think that special cap is worth it? I imagine it
will certainly prevent problems down the road with leaky and tired
electrolitics... someone should do a spread sheet on cost of purchase
VS long term service charges.... maybe the 4k isn't quite so bad....
Kent Pearson
On 11-Jan-2001, "Cybermonk" <gl...@blort.com> wrote:
> I have become more interested in full-power amps that have integrated
> attenuation of some sort, rather than low-power-only amps. The goal is to
> only have to buy 1 amp, not 4, that produces power-tube saturation in the
> home studio, cafe, club, or concert hall.
I can certainly relate to that. Amps are cool and all that, but I REALLY
don't need to have a house full of them. Nor do I want to fret about which
amp is right for which gig. The TSL100 solved that problem for me. It's
good for any situation I'll find myself in.
- KP
Lord Valve
> OK you should have specified it was a prototype and was 're-worked' a
> lot - but then - why mention all the re-working if that was the case?
> It's too bad you couldn't test a standard production amp though.
>
> But anyway - do you think that special cap is worth it? I imagine it
> will certainly prevent problems down the road with leaky and tired
> electrolitics... someone should do a spread sheet on cost of purchase
> VS long term service charges.... maybe the 4k isn't quite so bad....
I really don't know. The audiophools extol the virtues of bigass
poly caps routinely. They can certainly be shown to pass a
cleaner signal than an electrolytic does, from what I've heard.
They *do* have considerably lower ESR. I was thinking today
on whether or not it wouldn't be even better to use a multiplicity
of smaller-valued (and thus less expensive) caps of the
same type in parallel, since the ESR will be even lower.
I'm not sure why Dave picked a 250-volt part, either, since
the voltage across it won't ever exceed one tenth of the rating.
At any rate, that cap is the single biggest non-electrolytic
cap I've ever seen, and it was cool for that alone. ;-)
Lord Valve
RonSonic
<detr...@ix.netcom.com> wrote:
>> But anyway - do you think that special cap is worth it? I imagine it
>> will certainly prevent problems down the road with leaky and tired
>> electrolitics... someone should do a spread sheet on cost of purchase
>> VS long term service charges.... maybe the 4k isn't quite so bad....
>
>I really don't know. The audiophools extol the virtues of bigass
>poly caps routinely. They can certainly be shown to pass a
>cleaner signal than an electrolytic does, from what I've heard.
>They *do* have considerably lower ESR. I was thinking today
>on whether or not it wouldn't be even better to use a multiplicity
>of smaller-valued (and thus less expensive) caps of the
>same type in parallel, since the ESR will be even lower.
>I'm not sure why Dave picked a 250-volt part, either, since
>the voltage across it won't ever exceed one tenth of the rating.
>At any rate, that cap is the single biggest non-electrolytic
>cap I've ever seen, and it was cool for that alone. ;-)
I'm a bit curious about the value - seems far larger than needed - but
then it isn't my design and don't know what he heard or saw on the
scope to drive him to that. Even lunatic audio nuts running SE are
happy with 50-100 uF there on a final stage cathode bypass.
The voltage rating is probably just a matter of availability. By the
time you've wrapped a poly cap, if it is any good at all, it is good
for 200 volts. Almost harder to make a lower voltage unit. The biggest
audio related market for premium poly is the speaker guys and they
want a 200 V rating.
Nice to see glorious excess once in a while.
Ron
Dig it! http://www.flapcats.com
songs online at http://artists.mp3s.com/artists/122/flapcats.html
Miles O'Neal
>
> Lord Valve wrote:
>...I was thinking today
> >on whether or not it wouldn't be even better to use a multiplicity
> >of smaller-valued (and thus less expensive) caps of the
> >same type in parallel, since the ESR will be even lower.
> >I'm not sure why Dave picked a 250-volt part, either, since
> >the voltage across it won't ever exceed one tenth of the rating.
> >At any rate, that cap is the single biggest non-electrolytic
> >cap I've ever seen, and it was cool for that alone. ;-)
A friend of mine's dad was a hot shot
electroncis guy with the army, who used
to bring all sorts of oddball stuff home
to play with. He had a 10 or 15 farad
cap on his bench with *huge* insulators/terminals.
I thought it was a transformer at first.
>
> I'm a bit curious about the value - seems far larger than needed - but
> then it isn't my design and don't know what he heard or saw on the
> scope to drive him to that. Even lunatic audio nuts running SE are
> happy with 50-100 uF there on a final stage cathode bypass.
>
> The voltage rating is probably just a matter of availability. By the
> time you've wrapped a poly cap, if it is any good at all, it is good
> for 200 volts. Almost harder to make a lower voltage unit. The biggest
> audio related market for premium poly is the speaker guys and they
> want a 200 V rating.
The big deal about electrolytics has always been that
when you can use them, they could provide lots of
capacitance ina very small package compared to any
of the other types.
Bob
Sometimes I get to work on various things designed to be mounted on
poles or in the ground, or even on some vehicals, here in the cold,
cold, fucking cold, North.... its all Mil spec, and has to take from
minus 60C to plus 100C - there are very few electrolitics!! Lots of
boards are covered in lower value, high voltage polys... I love it
when I find a scrap one 'cause I get to take it home for salvage!!
Some have as many as 15 x 2uf caps to make up around 30uf at 350v.
Some boards have 60hz PASSIVE filters!! I have a few 30uf @ 100v from
one of these, and they were the smallest caps on the board!!
Jonathan Krogh
these 32uf 500v or so 'fast caps' at Angela Instruments site (same french
manuf.), and thought about eliminating the #1 wearout part in tube amps, the
electrolytics.
But then again , in DIY circles, amps regularly get picked apart to fuel
newer more attractive projects, and looking beyond a 15 year filter lifespan
is very rare.
RonSonic <rba...@gte.net> wrote in message
news:sd6u5tk5p4pjjroks...@4ax.com...
Maven Peal Instruments, Inc.
Lord Valve wrote:
> I really don't know. The audiophools extol the virtues of bigass
> poly caps routinely. They can certainly be shown to pass a
> cleaner signal than an electrolytic does, from what I've heard.
> They *do* have considerably lower ESR. I was thinking today
> on whether or not it wouldn't be even better to use a multiplicity
> of smaller-valued (and thus less expensive) caps of the
> same type in parallel, since the ESR will be even lower.
> I'm not sure why Dave picked a 250-volt part, either, since
> the voltage across it won't ever exceed one tenth of the rating.
> At any rate, that cap is the single biggest non-electrolytic
> cap I've ever seen, and it was cool for that alone. ;-)
Some caps that are manufactured so that they are essentially a number of
smaller ones in parallel (MIT Multicap for instance). Unfortunately, these
caps are all small valued. The value I needed was so large that I really
didn't have room to use a bunch of smaller ones. Besides, then you have
more solder joints etc...
The reason I used a 250V part is that it has the smallest voltage rating
you can easily get in this type of capacitor (as RonSonic pointed out).
The reason I used such a large value is to increase the bass response and
sustain.
The reason I used a poly can instead of an electrolytic is twofold: 1)
electrolytics just don't sound good to me, and 2) electrolytics only have
high effective capacitance at low frequencies. At high frequencies their
effectiveness goes to crap.
David Zimmerman
Maven Peal Instruments
Barry E. King
"Dave assures me that the currently-produced Zeetas
are much neater inside. I should hope so."
This pretty much did it for me the first time I read it. It implies rather
strongly that the amp being reviewed, which has been making its rounds to
various people in the USA for several months, that the specimen in question
was NOT a current production model.
Barry
Bob <Flin...@REMOVEMEvideotron.ca> wrote in message
news:3a5e7362...@news.videotron.ca...
Tom Plunket
day (my shop of choice 'though now I live 3000 miles away), and
was like "holy hell, I have to get one of these." Then I saw the
$3500 price tag and said "well, maybe tomorrow." ;) Can't
justify $3500 on an amp just yet...
-tom!
--
Happiness is one solid hunk of mahogany.
http://www.fancy.org/music/time/
email if you have a Time guitar for sale!
Tunes made with this fine device:
http://www.mp3.com/ticktock
Cybermonk
"Kent Pearson" <Blues...@aol.com> wrote in message
news:T_u76.4602$ct.4...@e420r-sjo3.usenetserver.com...
http://www.google.com/search?q=tsl100 - TSL100 search.
http://www.marshallamps.com/images/jcm2000tsl/tsl100w.htm
o Virtual Power Reduction [VPR] gives the extra saturation of a lower
powered valve amp being driven hard.
o Power Amp Mute switch for silent recording.
o D.I. XLR Output with acclaimed Marshall Speaker Emulation.
Does the VPR work? What type of attenuation is it - post-phase-interter
master volume like these amps? -- http://www.amptone.com/#ppmv
Kent Pearson
Yes, indeed. It works very well, and the sound is good. I've been told (by
Randall Aiken, I believe, that it's a sort of "fixed master" switch using
resistors, but I can't tell you if it's "post PI" or what. But again, it
works really well. I've used it to play backing up vocal groups, and as you
know, you need to lay low in that sort of a situation.
- KP
Miles O'Neal
>
> As quoted from the review:
> "Dave assures me that the currently-produced Zeetas
> are much neater inside. I should hope so."
>
> This pretty much did it for me the first time I read it. It implies rather
> strongly that the amp being reviewed, which has been making its rounds to
> various people in the USA for several months, that the specimen in question
> was NOT a current production model.
And in fact, back when Mr. Z was first talking
about sending one out for eval within AGA, he
made it clear he would be sending a prototype.
-Miles
Miles O'Neal
and for this much money they expected more.
That's a strange argument, if all too common. By
all means, if power is what you crave, go buy three
Marshall 100 watt heads for the price of a Zeeta.
Or siz to a dozen Sovteks, depending on where you
get 'em.
But then think about this. Every big, or even non-tiny,
act mics their amps. Leaf through any issue of Guitar
Player. Everything is mic'd - from Vox AC-15 to Marshall
Major. Eric Johnson, tone guru, mics everything, from
his pair of "dinky" BFDRs to his Marshall.
Yeah, there's something satisfying about a wall of
Marshalls, or Supers and Twins, or whatever.
But if the Zeeta sounds even half as good as GP thinks
it does, it's worth it. For another $100, you can get
another SM57 and mic cable at the music superstore of
your choice. If you play without a PA system in
public, you shouldn't be worrying about tone that much,
anyway.
-Miles