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el84/12ax7 se schematic needed!

tubo

Member
2007-04-01 9:04 pm
Chicago
Hello all,

i would like to build a simple el84 se amplifier for hifi. i do have almost all the parts and i just need a good sounding schematic. i searched the forum and found a couple that i like but i want a consensus on what everybody keeps going back to even if they have built better amps. i would like to stick with a 12ax7/ el84 se amp in pentode or triode.

there is a fellow forum member that have built a few 12ax7/ el84 amps from the same schematic he posted, but for the life of me cannot find that post.

1. i have 10 pairs of el84
2. i have 12 12ax7
3. all transformers needed


thanks
 

tubo

Member
2007-04-01 9:04 pm
Chicago
Thanks for the response fellas, Ive built the rh84 for a friend before and it sounded great. but i would like to stick with 12ax7s driving an el84 as i have a bunch that is not getting used.

Im googling it right now, and is browsing every thread under el84 when using the search function. more to go.
 
There is really no difficulty in designing such a two stage amplifier. I did that 10 years ago when I was 14 years old. I took the specs from the datasheet for the EL84 (250V, 48mA, 5K) and used the driver from another amplifier(EF40, the "old" EF86) and just put things together.

You don't have much to chose either. Different operating points for the ECC83 and different forms of feedback...that's all you can choose. When you have both systems from the ECC83 available for one channel, then you will have more possibilities (µ-follower, Cascode, Super-Triode, SRPP, etc.)