Charles - it is/was present with the Franks, Atma's, and Audions, though amplifier gain affected the ratio of signal to noise and hence how obtrustive it was. With the Audions I can eliminate it with low gain.
I am not certain that the CSL is the cause or contributor. It does not increase or decrease with CSL volume pot position, only power amp gain. Following the Jensen trouble-shooting guide, I'm left with:
In response to this discovery last year, I first tried a different cable (no difference), then I tried routing the cables completely away from any power cords or transformers...still no improvement. The only power line close to the cable is the PS cable for the CSL and that's DC. I eventually just lowered the gain on the Audions.
I am not certain that the CSL is the cause or contributor. It does not increase or decrease with CSL volume pot position, only power amp gain. Following the Jensen trouble-shooting guide, I'm left with:
the noise is coupling into to the cable by induction. This is most often caused by a
strong magnetic field near the cable. Such magnetic fields are produced by power wiring,
power transformers, and TV or computer CRT displays. Electrostatic coupling is also
possible, but rare in a cable which has a grounded outer shield. Route all signal cables to
avoid such strong fields.
In response to this discovery last year, I first tried a different cable (no difference), then I tried routing the cables completely away from any power cords or transformers...still no improvement. The only power line close to the cable is the PS cable for the CSL and that's DC. I eventually just lowered the gain on the Audions.