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Power amplifier EL 34

Koonw

Member
2013-04-09 9:37 pm
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You answered your question..You need a high mu voltage amp like a 6SL7 before the 6SN7..You have an IT is taking the place of coupling caps from the phase splitter but if you use the Tri/pent like a 6U8,6BL8.or7199,you will have to lose the innerstage. I would just add a 6SL7 or a 12AT7 in front of the 6SN7 and you will be good to go.
 
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miguelnoda

Member
2009-10-16 11:40 am
power amplifier el34

I've put a better 6SL7 and will need to know if I have to change the resistance of the cathode has more gain and I have to go up less volume
the concept is good or parallel would have to change
on the other hand I put resistors in the cathodes of independent EL34 12w 820ohn
 

Koonw

Member
2013-04-09 9:37 pm
I've put a better 6SL7 and will need to know if I have to change the resistance of the cathode has more gain and I have to go up less volume
the concept is good or parallel would have to change
on the other hand I put resistors in the cathodes of independent EL34 12w 820ohn

You'll get better bottom end response if you series the 2 primary windings and driven by a single 6sn7, using the other as gain stage. The give you 0.3V-p drive to full power.
 

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Why not just build the amp as is and build a separate preamp if you need one. If you do end up needing a preamp you can swap them out if you want to try something different.


Now that I think of it,you are probably right because this is using IT coupling and EL34 are relatively easy to drive and then he can just implement an extra stage later if he feels he needs more gain in the early stage.