fallsroad
100+ Head-Fier
- Joined
- Jan 20, 2007
- Posts
- 155
- Likes
- 10
Greetings all,
S/PDIF out -> MicroDAC (purchased June, 2007) --> McCormack Headphone amp/preamp --> McCormack power amp --> PMC TB2 speakers.
I'm getting an intense high frequency noise through my speakers. I've moved, connected and disconnected all of the gear in an effort to discover the problem, and as best I can tell it only occurs when the DAC is in the chain (My UPS may be a contributor, so I took that totally out of the equation and unplugged it).
The noise is independent of volume, whether I'm using the volume pot on my preamp or the software ones in Windows XP (which are usually kept at maximum). The noise is not a single tone but a continuous keening whistle and some hissing, if that makes any sense. The noise is also independent of input on the preamp - if I use an empty input the noise remains the same.
I subbed a USB cable, but that did not solve the problem. The only thing that seems to reduce it is to leave both SPDIF and USB connected at the same time, but the reduction in the noise is not enough for it to be negligible - it remains quite audible and terribly annoying.
No 60Hz hum is present at any time, fwiw.
I also noticed that with both cables connected I can only use the SPDIF input on the MicroDAC, even though the Windows settings remain the same. Is that normal? I was surprised to discover a rather different sound quality via USB than SPDIF as well - much brighter/thinner sounding.
Thanks for any help or suggestions.
S/PDIF out -> MicroDAC (purchased June, 2007) --> McCormack Headphone amp/preamp --> McCormack power amp --> PMC TB2 speakers.
I'm getting an intense high frequency noise through my speakers. I've moved, connected and disconnected all of the gear in an effort to discover the problem, and as best I can tell it only occurs when the DAC is in the chain (My UPS may be a contributor, so I took that totally out of the equation and unplugged it).
The noise is independent of volume, whether I'm using the volume pot on my preamp or the software ones in Windows XP (which are usually kept at maximum). The noise is not a single tone but a continuous keening whistle and some hissing, if that makes any sense. The noise is also independent of input on the preamp - if I use an empty input the noise remains the same.
I subbed a USB cable, but that did not solve the problem. The only thing that seems to reduce it is to leave both SPDIF and USB connected at the same time, but the reduction in the noise is not enough for it to be negligible - it remains quite audible and terribly annoying.
No 60Hz hum is present at any time, fwiw.
I also noticed that with both cables connected I can only use the SPDIF input on the MicroDAC, even though the Windows settings remain the same. Is that normal? I was surprised to discover a rather different sound quality via USB than SPDIF as well - much brighter/thinner sounding.
Thanks for any help or suggestions.
