Another update... haven't been able to get in touch with Jim for a second consultation, but now I'm fully convinced it's the front end tubes that are contributing to at least part of the choo-choo sound and buzz.
In the meantime, I've taken the gain down from 72 dB to 68 dB, which has at least ameliorated the noise.
I guess NOS tubes are the next step. Or maybe those Tung-Sol 12AX7s.
Patrick
In the meantime, I've taken the gain down from 72 dB to 68 dB, which has at least ameliorated the noise.
I guess NOS tubes are the next step. Or maybe those Tung-Sol 12AX7s.
Patrick

