16-09-2021, 06:21 AM
"I did have a major issue of self oscillating at something is excess of 20KHz" Did you connect the ground bus to the chassis? Could just be it being a SE Class A amp, I had similar issues with the PCL82 amp.It's a good idea to do a manual frequency sweep from 20hz to 100khz looking for an increase in THD. At the frequency where THD starts to increase fit a snubber. If no THD meter use Soundcard Scope which is free PC software that has FFT and an accurate THD meter.
3dB down at 9khz is dissapointing, could be the tfmr,well most likely the tfmr,but worth scoping the first stage just in case, though not sure what you can do if this is limiting HF response.
A lot of SE tfmrs have as you say E I lams but with thin paper fitted between the lams every 10 lams or so, it's often impossible to see it.
3dB down at 9khz is dissapointing, could be the tfmr,well most likely the tfmr,but worth scoping the first stage just in case, though not sure what you can do if this is limiting HF response.
A lot of SE tfmrs have as you say E I lams but with thin paper fitted between the lams every 10 lams or so, it's often impossible to see it.
