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6V6s in 6L6 amps
This directory contains USENET articles Mic
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Vacuum Tubes for Amps
6V6s in 6L6 amps
From Teleologis--(at)--orry.noEmail Thu Mar 21 13:26:51 CST 1996
Article: 11719 of alt.guitar.amps
From: Teleologist
Newsgroups: alt.guitar.amps
Subject: Re: Attention 6V6 experts - advice wanted!!!
Date: Thu, 21 Mar 1996 06:50:21 -0600
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Mic Kaczmarczik wrote:
>
> In article <314EA89F.3CD--(at)--orry.noEmail>,
> Teleologist wrote:
> >The reason for not using 6V6s in 6L6 amps has to do with the
> >impedance of the output transformer - it's typically too low for
> >6V6s & they draw too much current at full scream & die. That's
> >also why putting 6L6s in a 6V6 amp does not significantly raise
> >the wattage. The impedance is too high for the 6L6, but in this
> >case the tube is not damaged & in fact may live a very long life!
>
> Hmmm. If you had a 2x6L6 amp with a 4 ohm output transformer, say a
> Pro Reverb, could you use 2 6V6's if you increased the speaker
> impedance to 8 ohms? Or would the plate voltages typical for 6L6 amps
> still cause a problem?
>
I know a guy running 6V6s in a '65 Tremolux head with a stock 4 ohm output
transformer into an 8 ohm speaker emulator(GT Electronics). He told me he
has it biased at 25ma per tube with about 430 on the plates & the tubes
last about 500-600 hours(he 'cranks' it up!). With the higher voltage
Pro-Super power transformer, you could probably do it(but I've never tried
it!) with a well matched set of GTAs. You'd be running 'on the edge of
destruction'!(bringing the idle current down from 35-40ma to 20-25ma would
increase the voltage to something like 475-480). Probably wouldn't work on
a 50W SS or SF chasis.
The load impedance the tubes want to see varies with voltage & the curves
are different for the 6L6 and 6V6, but generally 6L6s want to see about
2/3rds the load of a 6V6.
From Teleologis--(at)--orry.noEmail Fri Mar 22 11:44:41 CST 1996
Article: 11775 of alt.guitar.amps
From: Teleologist
Newsgroups: alt.guitar.amps
Subject: Re: Attention 6V6 experts - advice wanted!!!
Date: Fri, 22 Mar 1996 07:38:50 -0600
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References: <4ihksb$av--(at)--ountain.mindlink.net> <314EA89F.3CD--(at)--orry.noEmail> <4in2kd$7--(at)--urly.cc.utexas.edu> <3151508D.637--(at)--orry.noEmail>
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Teleologist wrote:
>
>
> I know a guy running 6V6s in a '65 Tremolux head with a stock 4 ohm output
> transformer into an 8 ohm speaker emulator(GT Electronics). He told me he
> has it biased at 25ma per tube with about 430 on the plates & the tubes
> last about 500-600 hours(he 'cranks' it up!). With the higher voltage
> Pro-Super power transformer, you could probably do it(but I've never tried
> it!) with a well matched set of GTAs. You'd be running 'on the edge of
> destruction'!(bringing the idle current down from 35-40ma to 20-25ma would
> increase the voltage to something like 475-480). Probably wouldn't work on
> a 50W SS or SF chasis.
>
> The load impedance the tubes want to see varies with voltage & the curves
> are different for the 6L6 and 6V6, but generally 6L6s want to see about
> 2/3rds the load of a 6V6.
MORE:
One other thing to watch out for is that the filament voltage doesn't go to
high, especially if you have higher than average AC line voltages. Filaments
are supposed to get 6.3V+-.6 At higher voltages their life expectancy will
be shorter. This would probably affect preamp tubes more than the 6V6s which
will 'die' sooner from other causes.
One other alternative if you want a more 6V6-like sound is GE 6L6WGBs. These
have a mellower top end, areen't as loud, & break up easier than the Phillips
or Sovtek tubes. They also sound great in reissue Bassmans with a tube
rectifier & a rebias! Groove Tubes sells these as 6L6OS (old style) at some
pretty crazy prices - $120+/pair, you can usually find them for about
$60/pair at the usual NOS sources.
From timtub--(at)--ol.com Wed Mar 27 13:32:49 CST 1996
Article: 12027 of alt.guitar.amps
From: timtub--(at)--ol.com (TimTube)
Newsgroups: alt.guitar.amps
Subject: Re: Attention 6V6 experts - advice wanted!!!
Date: 27 Mar 1996 01:15:07 -0500
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In article <4j6tku$js--(at)--ewsbf02.news.aol.com>, tremolu--(at)--ol.com (Tremolux)
writes:
>
>>>>>Ah, think you got that backwards .... Most 6L6s with -35 to -37 on
the
>grids
>would be running very fat at about 45-60ma/tube. In a Deluxe that would
>drag
>all the voltages down
>
>I agree. Like I said, a re-bias is smart and essential.
>
OOPS,
My appologies, bass akwards I am.
Tim
A great amp can make a lousy guitar sound great.
A lousy amp will make a great guitar sound lousy.
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