Hello,
As debugged in another thread, my ST-70 is once again running good. Music sounds great but...I have a couple questions. I'm getting big vibration/hum out of the power transformer (so it seems). This (like everything else in the amp) is a brand new (triode electronics). Using a shorting cable diminished it a bit.
The buzz is also out of the speakers - quite loud when nothing is playing. I also am getting RF - I hear something (TV or radio) in both speakers as well as static. This was most pronounced late at night. I think it's contributing to the buzz problem.
Which brings me to the dirty mains...maybe. My house has odd wiring (seriously - 24V low voltage system throughout and flourescents (never on when listening)), When we moved in a new circuit box was installed. I also ran a dedicated line from my listening room to the breaker box and a dedicated 20A breaker. Despite this, if there is other significant electrical activity in the area (kitchen disposal or even turning on some lights) I notice my system 'pause' momentarily. This is most evident on vinyl as the turntable slows, but the tubes dim ad brighten up again.
So my question: How do I get the dimming tubes 'surge' to stop and what can I do about the RF (once that's fixed, I'll focus on the buzz should it still remain)?
Thanks!