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HELP convert el34 amp to 6v6s ?

2/2/2004 10:45 AM
gazza	HELP convert el34 amp to 6v6s ? Hi all. OK, how stupid is it to convert my 2el34 amp to run 6v6s ? why ? well i've got 6v6s and haven't got any el34s. And I never seem to turn the thing up very loud ! (I never end up with significant output tube distortion) will I be too far out on the output transformer ? (its only got taps for two el34s to 8ohms) but I have a choice of 4 or 16 ohm speakers to attach. so I should try to use the 16 ohm speakers ? I think the pinouts will be compatable ? SO, Is it just a matter of : i) lowering the B+ (and screens) from 420V to 300V ii) lowering the bias from -36V to ~18V ? will I be OK with i) if i put a big string of zenners on the (SS) earth connection of the rectifier (like 815V 5W zenners) ? will I need to be extra carefull with such a bigg voltage drop over the zenners ? I was hoping to mod the amp so that it will simply be a matter of swapping one wire over and turning the bias pot if I ever want to go back to el34s. Hope someone can put me straight ! Gareth.

2/2/2004 10:45 AM

gazza

HELP convert el34 amp to 6v6s ?

Hi all.

OK, how stupid is it to convert my 2*el34 amp to run 6v6s ?

why ? well i've got 6v6s and haven't got any el34s. And I never seem to turn the thing up very loud ! (I never end up with significant output tube distortion)

will I be too far out on the output transformer ? (its only got taps for two el34s to 8ohms) but I have a choice of 4 or 16 ohm speakers to attach. so I should try to use the 16 ohm speakers ?

I think the pinouts will be compatable ?

SO, Is it just a matter of :
i) lowering the B+ (and screens) from 420V to 300V
ii) lowering the bias from -36V to ~18V ?

will I be OK with i) if i put a big string of zenners on the (SS) earth connection of the rectifier (like 8*15V 5W zenners) ?

will I need to be extra carefull with such a bigg voltage drop over the zenners ?

I was hoping to mod the amp so that it will simply be a matter of swapping one wire over and turning the bias pot if I ever want to go back to el34s.

Hope someone can put me straight !

Gareth.

Replies:

shane Gareth420v is considered kinda ... -- 2/2/2004 12:00 PM
Bruce /Mission Amps Does this amp use a solid state rec... -- 2/2/2004 6:03 PM
gazza busy tweaking - where to bias ? -- 2/2/2004 9:35 PM
? Re: HELP convert el34 amp to 6v6s ? -- 2/3/2004 7:36 PM