To Aesthetix users

First tube-switching results:

I just switched the front pairs of 12AX7s - V1L and V2L into V1R and V2R.

The chuff-chuff cyclical sound and the 800 Hz buzz have now switched to the right channel. Still audible from the left, but much louder from the right.

I am now going to mix and match the tubes (I have marked them all.)

Patrick

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

You can try a quad of Ei 12ax7 tubes at $10 each. I use these in the Aesthetix Io's first stage as I have not yet been able to find a quad of Telefunken or Mullard that are as quiet as these.

Hi Patrick,

FWIW I have had good luck in sensitive Counterpoint products with RAM branded soviet and Yugo tubes from Roger Modjeski. Expensive but may be worth a try in your case.

Let us know how you get on.

Good Luck

I have found that Telefunken ECC83 (12AX7) in the V1 and V2 position significantly reduces noise level and provides incredible transparency.

Another ideal choice would be RCA black plate 12AX7/7025. A matched quad selected for low noise would suit the bill.

Tungsram 12AX7s are way less expensive and also dead quiet.