12AX7 Tubes For Poweramps...

[Greenevil]

Just wondering what 12AX7 tubes people are using in their Boogie poweramps and more so how it seems to effect the tone. I know how much of a difference it can make on a preamp but not sure how much it effects the poweramp and more specifically the role they 12AX7s play in a powermap...

Also, is the Strategy 400 a simul-class poweramp and can the 295 use all 6L6s?

 

[Cheycaster]

I was thinking the same thing. I know that when I hit the "loop switch" buttons the deep mode humms like crazy and really the other modes as well sound kinda dead to me. So I was wondering if it may be the tubes inside the power amps that do this or?? I know TIMBRE WOLF's recommendations are killer for the preamp and he has them for the power amps as well. I'm gonna try his tube info on mine ...
cheycaster

 

[FBMG]

The preamp tubes within the poweramp can make a big difference. I usually get several and try them out in each spot. I use all Boogie tubes and still the tonal differences of each is OBVIOUS. Basically you can adjust the tonal character of your sound globally this way but it takes patience and experimentation. Good Luck!

 

[disassembled]

I was thinking the same thing. I know that when I hit the "loop switch" buttons the deep mode humms like crazy and really the other modes as well sound kinda dead to me. So I was wondering if it may be the tubes inside the power amps that do this or?? I know TIMBRE WOLF's recommendations are killer for the preamp and he has them for the power amps as well. I'm gonna try his tube info on mine ...
cheycaster

Unfortunately the noise due to the modes on the 2:90 are just inherent in the design and have nothing to do with the tubes used. I always preferred the sound of the 2:90 with the modes off.

Retubing the whole power amp is just good practice IMO because most people ride their tubes to the death and only then do they realize the benefit of retubing every couple of years (if you use the amp a lot).

Greg

 

[Cheycaster]

Well, I am going to re-tube the the power amps I have 20/20 and a 2:90 tubed with with 7581-A's, military NOS 6L6's. Timbe Wolf says to use a 12BZ7 in the first driver spots and matched triodes in the PI spots. I'm glad I found this out from him and I am going to get these soon. As for the MODE switching I dont care for it at all. Sometimes it seems it would be a good idea but the tone and feel of them shy me away from using them.
cheycaster

 

[Greenevil]

Thanks for the useful info all, what is the PI spot?

 

[Cheycaster]

That is the 12AX7 tubes inside the power amps. One is a "driver" tube and the other two are PI's (Phase inverters) tubes for each channel, and using matched triodes would be a XLNT choice for these two spots.

 

[Greenevil]

Thanks for the info!

 

[Cheycaster]

Your welcome!