Deluxe Reverb at 16 ohms

[Tom Ginkel]

Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?

[RichL]

"Tom Ginkel" <tgi...@mchsi.com> wrote in message
news:qv6dnZkzP7QWxs7P...@mchsi.com...

> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?

As long as you don't disable the internal speaker, you'll be fine. This
will run your 16 ohm speaker and the internal 8-ohm speaker in parallel,
resulting in an effective speaker impedance of 1/(1/8 + 1/16) = 5.33 ohms.
But only 1/3 of the output power will be delivered to the external speaker;
2/3 of the output power will go to the internal speaker. Not only that, but
since the impedance match isn't optimum, overall power will be reduced.

I wouldn't run it with the internal speaker disabled though. Upward
impedance mismatches in a tube amp are not good!

[Lord Valve]

RichL wrote:

> "Tom Ginkel" <tgi...@mchsi.com> wrote in message
> news:qv6dnZkzP7QWxs7P...@mchsi.com...
> > Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
>
> As long as you don't disable the internal speaker, you'll be fine.

That's not what he asked, asswipe.

Lord Valve
expert (fuck you)

[Lord Valve]

Tom Ginkel wrote:

> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?

Depends on how many times you'd like it to fry
before you quit doing that. At 16 ohms, you'll
be looking at some high-tension flyback, which
will arc one tube socket - rendering the socket
and the tube in it useless. If you don't replace
the socket, it will continue to arc, putting your
output transformer at risk. Since the HT arcs
into the filament circuit, it will sometimes kill
preamp tubes too, although it's not a common
failure. Other things that can be impacted are
the HV filters and even the power transformer.
Sometimes you get lucky, and the arc is wholly
inside a power tube - but if you replace the tube,
it'll just arc the new one sooner or later. Bottom
line: don't do it. Now, some smart-ass college
boys are going to start erupting math from every
orifice they have and try to prove I'm wrong about
this, but I've been fixing arced-out Fenders for
longer than you've been breathing (unless you're
over 50) and I've seen a jillion of 'em...nearly all
were run into a 16-ohm load. And yours is full of
cheap-ass Chinese parts and machine-stuffed
circuit boards, a recipe for toast.

Lord Valve
Expert (and you know what you can do if you don't like it)

[WB]

On 10/7/2013 8:10 PM, Tom Ginkel wrote:
> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?

I've always heard if you must mismatch ... a lower value has less risk:


When using mismatched impedances between the amp and speakers there is a
greater strain on the output stage. Total output power to the speakers
is reduced, the tonal balance changes, and part of the output signal is
reflected back to the amp. This reflected signal can exceed the voltage
ratings of your output tubes and cause them to arc or short out - even
worse the output transformer can be damaged. Try to keep the output
below maximum, this will prevent possible problems.

Whenever you mismatch a tube amp with a much higher load (speaker)
impedance, a higher signal voltage is produced across the primary of the
output transformer. One loud popping note on the high E string and you
could arc-over the output tube sockets, fry the tubes, or zap the output
transformer. This is why you cannot run a tube amp without a speaker
connected to it. If you must mismatch the load impedance use a lower
than rated one, as you are doing now by connecting both cabinets.

Having said this, and making it very clear that I do not advise anyone
to connect a higher than rated impendence to any tube amp, generally
there is no problem when operating the amp at 8 ohms if your amp is well
designed and in good working condition. Connecting a 16 ohm load to a 4
ohm amp is, of course, more risky.

As with all tube amps the correct impedance setting for the amp is the
one that is the same as the total impedance of all the speakers that are
connected to it. Set the impedance selector in the back of your amp to
match the load (speaker) impedance that you are using.

You will get the same performance (but not necessarily the same tone)
with a 16 ohm cabinet by setting the selector to 16 ohms as you will if
you use a 4 ohm cabinet and set the selector to 4 ohms. If the amp has
no impedance selector (Fender Twin etc.) then choose a combination of
speakers that comes close to the rated impedance... preferably lower.

http://www.rickonslow.com/index.php?module=pnWikka&tag=ImpedanceMatching

[RichL]

"Lord Valve" <detr...@ix.netcom.com> wrote in message
news:525365D3...@ix.netcom.com...

He didn't say one way or another, stoogie.

[Lord Valve]

Sure - "Deluxe Reverb at 16 ohms" doesn't mean what it says.

The OP can tell you you're wrong - I'm done.

Cunt.

Lord Valve
Expert (fuck you)

[RichL]

"Lord Valve" <detr...@ix.netcom.com> wrote in message

news:52537645...@ix.netcom.com...

> RichL wrote:
>
>> "Lord Valve" <detr...@ix.netcom.com> wrote in message
>> news:525365D3...@ix.netcom.com...
>> > RichL wrote:
>> >
>> >> "Tom Ginkel" <tgi...@mchsi.com> wrote in message
>> >> news:qv6dnZkzP7QWxs7P...@mchsi.com...
>> >> > Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
>> >>
>> >> As long as you don't disable the internal speaker, you'll be fine.
>> >
>> > That's not what he asked, asswipe.
>>
>> He didn't say one way or another, stoogie.
>
> Sure - "Deluxe Reverb at 16 ohms" doesn't mean what it says.

"As long as you don't disable the internal speaker, you'll be fine."

You see a problem with that statement? Didn't think so.

[Carl]

Gee, I thought he answered that question exactly to the point of what the
asker wanted to know.

You should try to maintain a more normal, objective demeanor when someone
outside the political debate forum asks a serious question related to the
n.g.'s purpose. You demonstrated extremely bad form and could have stayed
out of the thread if you didn't want to help the OP with his question.

To Tom: ignore the irresponsible rhetoric. Rch was trying to help you.

[Carl]

RichL wrote:
> "Lord Valve" <detr...@ix.netcom.com> wrote in message
> news:52537645...@ix.netcom.com...
>> RichL wrote:
>>
>>> "Lord Valve" <detr...@ix.netcom.com> wrote in message
>>> news:525365D3...@ix.netcom.com...
>>>> RichL wrote:
>>>>
>>>>> "Tom Ginkel" <tgi...@mchsi.com> wrote in message
>>>>> news:qv6dnZkzP7QWxs7P...@mchsi.com...
>>>>>> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
>>>>>
>>>>> As long as you don't disable the internal speaker, you'll be fine.
>>>>
>>>> That's not what he asked, asswipe.
>>>
>>> He didn't say one way or another, stoogie.
>>
>> Sure - "Deluxe Reverb at 16 ohms" doesn't mean what it says.
>
> "As long as you don't disable the internal speaker, you'll be fine."
>
> You see a problem with that statement? Didn't think so.
>

Why argue with him? Your answer was on topic and helpful. Don't let him goad
you. It's a sickness.

[jh]

Am 08.10.2013 06:32, schrieb Rick N. Backer:

> On Mon, 07 Oct 2013 21:38:40 -0500, WB<n...@spam.ever> wrote:
>
>> On 10/7/2013 8:10 PM, Tom Ginkel wrote:
>>> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
>>
>>
>> I've always heard if you must mismatch ... a lower value has less risk:
>

> Wrong direction. Go higher on the speaker.

NOOOO

[jh]

Am 08.10.2013 06:31, schrieb Rick N. Backer:

> Bullshit. Running a 16 Ohm Celestion 70th Anniversary G12-H coupled
> to a Deluxe. Actually a clone Deluxe. Built that way. And still
> going rock solid even pushed hard. Maybe, Elvie, you need to learn
> how to build amps or quit working on shit. I suspect if the guy who
> built this only remembered 10% of what he knows he'd still kick your
> butt in spelling bee. Fuckin' hack.


I hate to sy it, but LV is correct.

If *YOU* have done it for "along time", then the "magical event" has
simply not occurred yet. Arc-Over due to flyback is a "one time
incident" - depending on the actual Voltage, humidity, dirt and dust at
the socket etc... ZAPP.

The only functional precaution are the "flyback diodes" at the socket �
la trainwreck. They prevent the plate of the "cutoff-side" to go
negative - thus eliminating the "ignition coil reaction" of the pp
output transformer.

I took a look at the spikes in my DIY SR once - i stopped at 2,5KV....
With the diodes you have a max of approx 2*B+.

regards

Jochen

[jh]

Am 08.10.2013 06:27, schrieb Rick N. Backer:

> On Mon, 7 Oct 2013 20:10:33 -0500, "Tom Ginkel"<tgi...@mchsi.com>
> wrote:
>
>> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
>

> None.

wrong

[jh]

Am 08.10.2013 06:38, schrieb Rick N. Backer:
> On Mon, 7 Oct 2013 20:10:33 -0500, "Tom Ginkel"<tgi...@mchsi.com>
> wrote:
>

>> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
>

> Give this a read. Mesa has sold a lot more fuckin' equipment that
> Elvie can hope to see in a fuckin' lifetime. It's Mesa oriented but
> the theory doesn't change.
>
> http://mesaboogie.com/news/2013/06/mesaboogie-speaker-impedance-matching-and-hook-up-part-1/


you're sure he has got the theorie? Reread the bias document...
With all respect, but Randall has not reinventet tube amps; but he has a
very good marketing

Are you sure his amps don't have the diodes fitted in the PA?
there are old Boogies who have them; don't know about newer ones.
With diodes fitted in my amps, I'd also say one "up or down" is ok...

AND:
i havereplaced arced tube socket in Rectifiers - at least three times
...Upward mismatch. 8 Ohm Amp in 16 Ohm Cab ;-) Metal Bands

Please show me a burned/overloaded output transformer due to downward
mm; I'll show you dozens of sockets, OTs, arced tubes due to upward mm....


*) my personal collection of damage culprits....

regards

Jochen

[WB]

On 10/7/2013 11:32 PM, Rick N. Backer wrote:
> On Mon, 07 Oct 2013 21:38:40 -0500, WB <n...@spam.ever> wrote:
>

>> On 10/7/2013 8:10 PM, Tom Ginkel wrote:
>>> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
>>
>>
>> I've always heard if you must mismatch ... a lower value has less risk:
>

> Wrong direction. Go higher on the speaker.
>

lower on the speaker

[morris....@gmail.com]

Yeah, it's upward mismatches that cause flyback voltage spikes.

Downward ones will pull more current through the power tubes and wear them out faster, possibly. Aren't there only so many Coulombs in a cathode?

If he must mismatch up, definitely flyback diodes might help. As might prayer. And tho it would definitely cause a loss of treble, possibly noticeable, he might want to increase the grid resistors of the power tubes as well. I believe JjTJ once posted the schem of a small amp that actually could run with headphones as a load with the speaker completely disconnected - the punchline is that the thing had monstrously huge grid resistors to ward off grid conduction shifting the bias with consequent 'crossover' cutoff and flyback spikes.

[Lord Valve]

You're an ass. Stick to eyeglasses.

[Lord Valve]

"Rick N. Backer" wrote:

> On Mon, 07 Oct 2013 21:38:40 -0500, WB <n...@spam.ever> wrote:
>

> >On 10/7/2013 8:10 PM, Tom Ginkel wrote:
> >> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
> >
> >
> >I've always heard if you must mismatch ... a lower value has less risk:
>

> Wrong direction. Go higher on the speaker.

I'll let someone else hand you your ass. ROFLMBFAO!

[Lord Valve]

> I hate to say it, but LV is correct.

God, that's gotta smart. I'll send you a sympathy card, ok?

> If *YOU* have done it for "along time", then the "magical event" has
> simply not occurred yet. Arc-Over due to flyback is a "one time
> incident" - depending on the actual Voltage, humidity, dirt and dust at
> the socket etc... ZAPP.
>
> The only functional precaution are the "flyback diodes" at the socket �
> la trainwreck. They prevent the plate of the "cutoff-side" to go
> negative - thus eliminating the "ignition coil reaction" of the pp
> output transformer.

...

However, they will short when presented with a spike
that exceeds the PIV - even when there are two or three
in series, as is often done. This dumps the plate supply
directly to ground, blowing the fuse. While this (usually)
prevents a socket arc, subsequent fuses installed by
the asshole (oops, I mean "guitar player") are often
a bit larger than recommended (can you say 15 amp
slo-blo? We knew ya could...) and all sorts of shit fries
from then on out. Aluminum foil works well, too...note
to self: send a letter of thanks to the Reynolds Aluminum
folks for their fine product, which has bought me a whole
shitload of cool stuff....

> I took a look at the spikes in my DIY SR once - i stopped at 2,5KV....
> With the diodes you have a max of approx 2*B+.

5K and higher is not uncommon.

Lord Valve
Expert (and fuck anyone who doesn't like it)

[Defiant]

Cock N Sucker must be a graduate of the Ravaged Sphincter school
of electronical engineerin'. Heh!

[Squier]

> Tom Ginkel <tgi...@mchsi.com> wrote:

> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?

usually a thread like this turns into a circle jerk of techs with
an additional pissing contest as a side show. Toss in some academic
high wired acts and you have a 3 ring circus that won't leave town.

The really simple answer is: yes you will run into problems eventually,
perhaps not right away (playing a few minutes) but probs will arise if
you have the amp on for long sessions into a 16 ohm lead (assuming you
are talking about changing out the internal speaker to a 16ohm speaker
and running the cab normally as a 1x12 combo using the internal speaker).

So just install an 8 ohm speaker and be done with it.
If you want to run an extension cabinet then use an 8 ohm extension cab.
The 2 speakers are in parallel so the total ohms/resistance would be 4 ohms
which is still safe for that amp. (running a 4 ohm load will only wear out
the 6V6 power tubes a little faster).

Now if you want to always run that amp with an extension can hooked up
then you can certainly install a 16 ohm internal speaker and then hook
up a 16ohm external cab so the total (in parallel) would be 8 ohms and
that would be fine for that amp -- but don't forget to hook up that extension
cab so that you are not running just the internal 16ohm speaker.

And yeah - I am not some amp 'tech' but I do know how to give simple
and accurate answers -- that even occasionally if those answers are slightly
flawed -- always err on the side of caution.

I am sure you CAN run a 16 ohm load with that amp and nothing might
ever happen until you decide to let it run for a few hours during a
lengthy gig session... and then... you'll have to bring it to an amp
tech and by the many responses you have gotten from these types on this thread -
do you really want to have to deal with them ?

So 8 ohms total or 4 ohms (total) is fine. Leave it at that.

[Lord Valve]

"Rick N. Backer" wrote:

> Well. I'm not going to argue anymore.

Because you're full of shit, and figured it out. Good 'boon!

> He bulids them all that way

Maybe you should ask him if he's using an OPT with a 16-ohm secondary.

Wait, I don't know how a cathode follower works. Never mind.

[Tom Ginkel]

Thanks LV. Experience speaks for itself. Think I'll put the Celestion
Century Neo, 16 ohm, in the extension cab and keep the 8 ohm speaker mounted
in the Deluxe. I don't always use the extension.

"Lord Valve" wrote in message news:525368AE...@ix.netcom.com...

[Tom Ginkel]

Thanks Rich. Between you and LV, I got my problem solved.

"RichL" wrote in message
news:CuOdncIiV8yi_s7P...@supernews.com...

"Tom Ginkel" <tgi...@mchsi.com> wrote in message
news:qv6dnZkzP7QWxs7P...@mchsi.com...

> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?

As long as you don't disable the internal speaker, you'll be fine. This
will run your 16 ohm speaker and the internal 8-ohm speaker in parallel,
resulting in an effective speaker impedance of 1/(1/8 + 1/16) = 5.33 ohms.
But only 1/3 of the output power will be delivered to the external speaker;
2/3 of the output power will go to the internal speaker. Not only that, but
since the impedance match isn't optimum, overall power will be reduced.

I wouldn't run it with the internal speaker disabled though. Upward
impedance mismatches in a tube amp are not good!

[Tom Ginkel]

My, this was certainly enlightening!

One more question. Will presenting the Deluxe with a 4 ohm load (8 ohm
internal with 8 ohm extension) or 5.33 ohm load (8 ohm internal with 16 ohm
extension) be preferable?



"Squier" wrote in message news:081020131138233991%squ...@strats.net...

[Squier]

> Tom Ginkel <tgi...@mchsi.com> wrote:

> My, this was certainly enlightening!
>
> One more question. Will presenting the Deluxe with a 4 ohm load (8 ohm
> internal with 8 ohm extension) or 5.33 ohm load (8 ohm internal with 16 ohm
> extension) be preferable?

The transformer in that amp is tapped sepcifically for either a 4 or 8 ohm load.
The amp will perform at its best at these resistance values.
Running the amp at anything in between 4 to 8 ohms is acceptable and will
not cause any problems with the amp although it will not run at its rated
best performance. Keep in mind that running speakers with different ohm values
that when connected in parallel (internal speaker + extension cab) that
allow a total ohm reading of 5.33 ohms also means that each speaker because
of its different resistance (ohm rating) will not receive equal power (watts)
being delivered to each speaker. This may or may not be a concern to you
especially if each speaker has different efficiency ratings (decibels per 1 watt)
and the speaker getting less wattage delivered is of higher efficiency so
that in the actual perception of volume being delivered -- when you step back
from your rig (combo + extension) -- you don't seem to think that one speaker
is necessarily louder than the other and you have a nice blend that sounds like
one big speaker.

Whew. You might be sarcastic with me -- but that's ok.
If you want a long drawn out answer and are baiting me -- then please read
all the other reply posts that go on and on rather than giving you a simple answer
as I have tried to do here.

Ah well -- most solid state amps have no problem running various ohm loads
and are far more tolerant to these issues... but such is the way of amps with
tube power sections.

[Lord Valve]

Squier wrote:

> > Tom Ginkel <tgi...@mchsi.com> wrote:
>
> > My, this was certainly enlightening!
> >
> > One more question. Will presenting the Deluxe with a 4 ohm load (8 ohm
> > internal with 8 ohm extension) or 5.33 ohm load (8 ohm internal with 16 ohm
> > extension) be preferable?
>
> The transformer in that amp is tapped sepcifically for either a 4 or 8 ohm load.

No, it isn't. It has a single 8-ohm secondary. Shut up.

http://ampwares.com/schematics/65_Deluxe_Reverb_RI.pdf


Lord Valve
Expert (fuck you if you don't like it)

[Lord Valve]

Tom Ginkel wrote:

> My, this was certainly enlightening!
>
> One more question. Will presenting the Deluxe with a 4 ohm load (8 ohm
> internal with 8 ohm extension) or 5.33 ohm load (8 ohm internal with 16 ohm
> extension) be preferable?

If you want the two speakers to share the amp's power equally,
two 8-ohm loads will be preferrable. If you want to split hairs,
a 5.33-ohm total load will wear the power tubes out a bit less
quickly than a 4-ohm load will.

Lord Valve
Expert (fuck anyone who doesn't like it)

[Squier]

So a small detail makes the rest of my good advice suddenly bad ?
I think not. Everything else I have said is correct with the main
topic being what will be bad for the amp. Also correct.

Reading through the reply threads -- the first thing you posted was
to call someone else a name -- you didn't even offer any direct advice
to the posters question anywhere within your first several replies.

You were more concerned that by putting someone else down that somehow
you look better. Hey -- why don't you actually use yur knowledge to
give clear and concise replies to people's questions rather than waiting
for someone else to offer help and then simply nit-pick.

It doesn't make you appear any more knowledgeable and rather is
just makes you appear to be a sore old sod not really helaping anyone at all.

What happened along the way old timer ?

[Lord Valve]

Squier wrote:

> > Lord Valve <detr...@ix.netcom.com> wrote:
>
> > Squier wrote:
> >
> > > > Tom Ginkel <tgi...@mchsi.com> wrote:
> > >
> > > > My, this was certainly enlightening!
> > > >
> > > > One more question. Will presenting the Deluxe with a 4 ohm load (8 ohm
> > > > internal with 8 ohm extension) or 5.33 ohm load (8 ohm internal with 16 ohm
> > > > extension) be preferable?
> > >
> > > The transformer in that amp is tapped sepcifically for either a 4 or 8 ohm load.
> >
> > No, it isn't. It has a single 8-ohm secondary. Shut up.
> >
> > http://ampwares.com/schematics/65_Deluxe_Reverb_RI.pdf
> >
> >
>
> So a small detail makes the rest of my good advice suddenly bad ?

Shut up.

[RS]

On Wed, 09 Oct 2013 08:33:41 -0400, Squier <squ...@strats.net> wrote:

>> Lord Valve <detr...@ix.netcom.com> wrote:

>> [Crap snipped]

>Reading through the reply threads -- the first thing you posted was
>to call someone else a name -- you didn't even offer any direct advice
>to the posters question anywhere within your first several replies.
>
>You were more concerned that by putting someone else down that somehow
>you look better. Hey -- why don't you actually use yur knowledge to
>give clear and concise replies to people's questions rather than waiting
>for someone else to offer help and then simply nit-pick.
>
>It doesn't make you appear any more knowledgeable and rather is
>just makes you appear to be a sore old sod not really helaping anyone at all.
>
>What happened along the way old timer ?

He's a back woods checker player who has convinced himself that he's
Garry Kasparov. Calling yourself "Lord" whatever is usually the first
clue about cluelessness. He knows very little about electronics, and
as many are noticing, he makes his big splash by trying to bully
people. The attempt to beat anyone up with 'impedance' is a
particularly humorous turn, as most in aga know.

I'll have a bit more time this week, so maybe Valvie and I can talk
about electronics. :-) Meanwhile, don't be too concerned about what
the loser says. He'll run away soon, as all loud bullies do.

[RS]

On Wed, 09 Oct 2013 06:03:53 -0600, Lord Valve
<detr...@ix.netcom.com> wrote:

>No, it isn't. It has a single 8-ohm secondary.

>Lord Valve
>Expert (fuck you if you don't like it)

They should have used one o' them fancy Lord Valve type sub-micro-ohm
output transformers. That would match up with just about anything, for
...you know...'1 to 10 maximum voltage transfer' and all. (gak)

Why the hell is Valve trying to post about electronics again? I
thought we had covered this.

"Lord Valve" wrote:
"I've run EL34s in Twins for years on end with no problem,"

Valvosaurus, what happens with regard to reflected impedance when you
do that? Try to answer all by yourself first, with no help from your
two brothers Cleefus and Cleefus.

This should be good.

[WB]

On 10/9/2013 7:33 AM, Squier wrote:

> It doesn't make you appear any more knowledgeable and rather is
> just makes you appear to be a sore old sod not really helaping anyone at all.
>
> What happened along the way old timer ?
>

Having a failing business and a black POTUS has certainly soured him .


hahahaaa

[RS]

Morris,

Nothing about transformers for now. Just a reminder that the Audio
Electronics Society show is at the Javitts Convention Center in NYC
Oct 17-22. If you're nearby, it would probably be worthwhile. I did
confirm that THAT Corp (VCA chips) will be there. Usually lots of cool
stuff. I may be able to find you a link for free passes, though I'm
not sure what the cutoff date is.

[RS]

On Wed, 09 Oct 2013 00:13:28 -0400, Squier <squ...@strats.net> wrote:

>> Tom Ginkel <tgi...@mchsi.com> wrote:
>
>> My, this was certainly enlightening!
>>
>> One more question. Will presenting the Deluxe with a 4 ohm load (8 ohm
>> internal with 8 ohm extension) or 5.33 ohm load (8 ohm internal with 16 ohm
>> extension) be preferable?
>
>The transformer in that amp is tapped sepcifically for either a 4 or 8 ohm load.
>The amp will perform at its best at these resistance values.

Not strictly 'tapped,' but that was the intended impedance range. And
of course 5.33 is within that range. A lot of this depends on how
hard the amp will be pushed. The typical 'sure-thing' flyback spike
generator is a Marshall with its retardedly designed impedance
selector plug fallen out (or speaker end of the cable unplugged).
Shredder plugs in...no sound, so the obvious thing is to turn it up to
10 and bang some Peter Townshend chords. That usually fixes 'em.

>Running the amp at anything in between 4 to 8 ohms is acceptable and will
>not cause any problems with the amp although it will not run at its rated
>best performance.

Another thing to keep in mind: Two speakers will usually just sound
bigger. There's a choral effect from the slightly different phasing
and response characteristics, even when using two of the same model of
speaker. That has less bearing if you're recording of course, since
you can do something similar with multiple mics. But for live,
especially a small, relatively low-volume gig, a single speaker can be
pretty unidirectional and 'small.' Adding the second speaker can open
things up and make a big perceived difference even if the efficiency
is not exactly optimum. (It will still be OK at 4 or 5.33 ohms)

[RS]

On Tue, 08 Oct 2013 11:38:23 -0400, Squier <squ...@strats.net> wrote:

>> Tom Ginkel <tgi...@mchsi.com> wrote:
>
>> Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
>
>usually a thread like this turns into a circle jerk of techs with
>an additional pissing contest as a side show. Toss in some academic
>high wired acts and you have a 3 ring circus that won't leave town.

I believe you now have some direct experience in how that comes about.

[Lord Valve]

Stick your pop quiz up your ass.

[RS]

On Wed, 09 Oct 2013 14:57:41 -0600, Lord Valve

Excellent answer, as always. Now try to creep away so no one notices
your lack of electronics chops. And leave the nice people alone so
you don't embarrass yourself any more.

[???]

Did you notice that he said "tapped" for EITHER 4 or 8 ohms. If he thought that there was an actual tap on the secondary, he would've said BOTH. I think that he misused the word "tapped" when he meant WOUND. It's obvious in another post that he knows that it's a single winding.

And I've heard from an ACTUAL expert that Fender purposely specs the secondary so that the impedance ratio for the load w/o the extension isn't really the perfect load, so that you can run an extension without having as big of an impact on power tube life. Although I've never experimented to find out if they will produce more power somewhere between the two rated impedances.

[???]

The power ratio is not the only factor. RELATIVE SENSITIVITY is just as important. And, per my previous post, that amp might actually be more efficient somewhere between 4 and 8 ohms.

[Lord Valve]

??? wrote:

> On Wednesday, October 9, 2013 5:03:53 AM UTC-7, Lord Valve wrote:
> > Squier wrote:
> >
> >
> >
> > > > Tom Ginkel <tgi...@mchsi.com> wrote:
> >
> > >
> >
> > > > My, this was certainly enlightening!
> >
> > > >
> >
> > > > One more question. Will presenting the Deluxe with a 4 ohm load (8 ohm
> >
> > > > internal with 8 ohm extension) or 5.33 ohm load (8 ohm internal with 16 ohm
> >
> > > > extension) be preferable?
> >
> > >
> >
> > > The transformer in that amp is tapped sepcifically for either a 4 or 8 ohm load.
> >
> >
> >
> > No, it isn't. It has a single 8-ohm secondary. Shut up.
> >
> >
> >
> > http://ampwares.com/schematics/65_Deluxe_Reverb_RI.pdf
> >
> >
> >
> >
> >
> > Lord Valve
> >
> > Expert (fuck you if you don't like it)
>

> Did you notice <smack>

Shut up. You're as clueless as he is.

[Lord Valve]

Wrong. Shut up.

[Tom Ginkel]

I am not in any way looking for anything but good information.

The deal is, I have a very sensitive Celestion Century (102 db) that is 16
ohms that I wish to put in the extension cab. I'm thinking it might balance
well with my 98 db, 8 ohm Weber in the amp.

At any rate, you guys really educated me about the topic and I feel a lot
better informed. Thanks!

"Squier" wrote in message news:091020130013280510%squ...@strats.net...

[Tom Ginkel]

Thanks again. Appreciate your real-world savvy. I think I actually
understand the topic, not in spite of, but due to all the differring
opinions.

"Lord Valve" wrote in message news:5255475A...@ix.netcom.com...

[Tom Ginkel]

Pretty damned fun, actually. Love the cast of characters and respect their
knowledge.

"RS" wrote in message news:9lcb59hu2tbtml2ne...@4ax.com...

[???]

You just made my point (in a previous post) that sensitivity is just as important as impedance. In fact, your 16 ohm speaker will likely sound louder. The power amp MAY actually put out more power than at 8 or 4 ohms.

Lucky_Stiff
NOT an "expert," but often ace out the self-proclaimed bigot.

[RS]

On Wed, 9 Oct 2013 20:41:18 -0500, "Tom Ginkel" <tgi...@mchsi.com>
wrote:

>Pretty damned fun, actually. Love the cast of characters and respect their
>knowledge.

This group used to have quite a few great engineers, but you can see
what's happened to it as a result of a few loons. There are still
some very knowledgeable people here. Rich L is a physicist. I'm an
electronic engineer. Lucky Stiff also knows his stuff (not sure if
he's an EE). Squier posts helpful and insightful info. You'll notice
that many of us are not overly impressed with Valve (Lots of trash
talk, very few actual electronics chops).

In any case, you're good with your current speakers. The more
efficient 16 ohm will probably keep up fine with the less efficient 8
(may even be louder). I believe Lucky Stiff already mentioned this. In
any case, the 'sum is often greater...' as they say. The simple fact
of two separate speakers will add dimension to your sound.

Glad you posted. The more faint of heart generally take one look and
give aga a pass.

[RS]

On Wed, 09 Oct 2013 14:57:41 -0600, Lord Valve

<detr...@ix.netcom.com> wrote:

>RS wrote:
>
>> On Wed, 09 Oct 2013 06:03:53 -0600, Lord Valve

>> "Lord Valve" wrote:
>> "I've run EL34s in Twins for years on end with no problem,"

>> Valvosaurus, what happens with regard to reflected impedance when you
>> do that?

>Stick your pop quiz up your ass.

By the way, you evidently didn't understand that was not a pop quiz.
Mullard's suggested plate-to-plate primary spec for fixed bias
push-pull EL34's is around 3k. Conventional suggested primary for
6L6's is around 6k. Did you know that the output tubes can have a
major effect due to reflected impedance? How do you suppose that
affects an amp with a transformer designed for 6L6's? No need to
answer.

[Lord Valve]

RS wrote:

> On Wed, 09 Oct 2013 14:57:41 -0600, Lord Valve
> <detr...@ix.netcom.com> wrote:
>
> >RS wrote:
> >
> >> On Wed, 09 Oct 2013 06:03:53 -0600, Lord Valve
> >> "Lord Valve" wrote:
> >> "I've run EL34s in Twins for years on end with no problem,"
>
> >> Valvosaurus, what happens with regard to reflected impedance when you
> >> do that?
>
> >Stick your pop quiz up your ass.
>
> By the way, you evidently didn't understand that was not a pop quiz.

...

BTW, you evidently don't understand that I don't give a rusty
rat-fuck for you or any of your luntzmen. You can sing whatever
lame tune you'd like, but you're dancing alone.

Fuck off.

[RS]

On Thu, 10 Oct 2013 05:37:07 -0600, Lord Valve

<detr...@ix.netcom.com> wrote:

>RS wrote:
>
>> On Wed, 09 Oct 2013 14:57:41 -0600, Lord Valve
>> <detr...@ix.netcom.com> wrote:
>>
>> >RS wrote:
>> >
>> >> On Wed, 09 Oct 2013 06:03:53 -0600, Lord Valve
>> >> "Lord Valve" wrote:
>> >> "I've run EL34s in Twins for years on end with no problem,"
>>
>> >> Valvosaurus, what happens with regard to reflected impedance when you
>> >> do that?
>>
>> >Stick your pop quiz up your ass.

>> you evidently didn't understand that was not a pop quiz.

You must have mistakenly erased this part:

>> Mullard's suggested plate-to-plate primary spec for fixed bias
>> push-pull EL34's is around 3k. Conventional suggested primary for
>> 6L6's is around 6k. Did you know that the output tubes can have a
>> major effect due to reflected impedance? How do you suppose that
>> affects an amp with a transformer designed for 6L6's? No need to
>> answer.

>BTW, you evidently don't understand that I don't give a rusty
>rat-fuck for you or any of your luntzmen. You can sing whatever
>lame tune you'd like, but you're dancing alone.

I did say: "No need to answer." You make it more apparent that you
really don't know this stuff. Here you are acting smug cause you
think you finally got one o' those impedance questions right. But it
turns out that you may or may not be sending amps out with upward
speaker mismatches--exactly what you advised the OP against.

Meanwhile, in other aga threads, you're advising that it's fine to
swap output tubes in and out of amps that weren't designed for them.
(Maybe we'll talk about filament power for EL34's vs 6L6's later)

So here's the question that I'm sure you're trying to look up now:
In which direction will the mismatch occur: Are those amps mismatched
with speaker impedances on the high side, or on the low side?

>Fuck off.

Now now, if you're gonna be snippy, you're just gonna have to figure
this out all by yourself.

[RS]

On Thu, 10 Oct 2013 10:17:54 -0700, Rick N. Backer
<ken.w...@shawNO.caSPAM> wrote:

>On Thu, 10 Oct 2013 05:37:07 -0600, Lord Valve

>Vagina speak for "fucked if I know!"

I'm hoping for a list of famous artists who love their 'expert' amp
mods...'tick' 'tick' 'tick'...

Maybe Valvie and that other 'amp expert' got a good deal on fire
extinguishers.

[RS]

On Fri, 11 Oct 2013 12:33:11 -0700, Rick N. Backer
<ken.w...@shawNO.caSPAM> wrote:

>On Mon, 7 Oct 2013 20:10:33 -0500, "Tom Ginkel" <tgi...@mchsi.com>
>wrote:
>

>>Any problems running my 65 Deluxe Reissue with a 16 ohm speaker?
>

>Does anyone here know what a snubber diode is? Just curious.

Hi Ken,

When a tube amp is run without a speaker connected, the output tubes
still try to send signal to the output transformer secondary. But
since there's no speaker to load it down, the signal goes nowhere and
fires back into the primary. Since that reverse path has a high
-upward- turns ratio, (8 ohms to say 6000 or so), the signal is
amplified.

IOW transformers can operate in both directions. In this case, primary
(Tubes side) -> secondary (speaker side) is 'step-down', but the
reverse works as a step-up.

That happens to a lesser degree even if something is hooked to the
secondary but its impedance is higher than the rated (or equivalent)
transformer impedance. That's basically what this thread was
about....avoiding those 'flyback' spikes.

One way to guard against that is to use heavy-duty diodes to shunt
spikes to ground so they don't damage anything on the primary side.
Morris touched on that earlier in the thread.

It's something that Valve probably should have installed on his Fender
Twin EL34 conversions, had he a clue about what he was doing.