Hi,
I am running for some years now the ul40s2 from Menno with the autobias:
Autobios improved
Everything is nice and quiet. I am running this amp in ultralinear.
I have just pulled the el34 and plugged 6550 from svetlana in withou changing anything else.
i got a huge hummmm...music could be played, but the humm was a lot. I plugged in a matched quad of kt88 of the treasury series...same behavior.
This is issue no 1. No idea why this can happen.
Worse, I plugged in the el34, and zhe amp was not quiet anymore. slight hum, but the channel as well is now not as loud as the other anymore (i did this experiment only on one channel). I did not change anything in the autobias module or anything.
What happened here ?
Thanks for your support
I am running for some years now the ul40s2 from Menno with the autobias:
Autobios improved
Everything is nice and quiet. I am running this amp in ultralinear.
I have just pulled the el34 and plugged 6550 from svetlana in withou changing anything else.
i got a huge hummmm...music could be played, but the humm was a lot. I plugged in a matched quad of kt88 of the treasury series...same behavior.
This is issue no 1. No idea why this can happen.
Worse, I plugged in the el34, and zhe amp was not quiet anymore. slight hum, but the channel as well is now not as loud as the other anymore (i did this experiment only on one channel). I did not change anything in the autobias module or anything.
What happened here ?
Thanks for your support