Aikido 6GM8 - headphone stage

[lordearl]

I am currently finishing a build of the 24V 6GM8 / ECC86 Broskie Aikido line stage amplifier and the space I have in the chassis is very minimal.

Is there a simple way to modify the standard circuit to allow for headphone use? For example, can we increase the value of the output caps (C3) to ensure the frequency response for headphones is adequate?

 

[lineup]

Nice Idea, @lordearl

 

[6L6]

Yes, increasing C3 will be the first step, and perhaps the only step needed. Start by paralleling 47uF across whatever film cap is there currently.

 

[Ixnay]

Interestingly, I bought a pre built version of this as a headphone amp and the bias being set quite high seemed to make it one of the very best sounding headphone amps that I ever owned.

 

[woodturner-fran]

Broskie did a version of this using 2x LM317 per channel arranged on the outputs as followers to give some current drive
https://tubecad.com/2008/01/blog0132.htm

but it seems he changed from that afterwards.

 

[Ixnay]

Yes, as I recall the 317 outputs were in the design that I had. Again, just sound that was impossible for me to define. You just had to sit down and enjoy it and forget the rest.