Since many of you on here build your own DACs, I thought you might be able to give me a clue to what's wrong with mine. It's an older Musical Fidelity A3.24, which was one model down from their flagship when it was made. For several years, it sometimes makes a loud 'pop' when I insert a new CD into the transport. It does this with different transports, but it's currently hooked to a Pioneer Elite DVD player.
When it does this, the "Locked" LED on the front panel blinks. But it doesn't do it every time a new CD goes in. I haven't been able to discern any pattern to it. I've just gotten into the habit of muting my preamp every time I change CDs.
Are DACs supposed to mute any un-musical signals related to getting a digital signal lock?
When it does this, the "Locked" LED on the front panel blinks. But it doesn't do it every time a new CD goes in. I haven't been able to discern any pattern to it. I've just gotten into the habit of muting my preamp every time I change CDs.
Are DACs supposed to mute any un-musical signals related to getting a digital signal lock?
Yes, commercial DACs mute sound output, like ’pops’, whenever non-Audio data is presented to the D/A chip. Such as when signal-lock is lost.
It would be good practice for a DAC to mute its output when the S/PDIF receiver's out of lock. The alternative to that might be very undesirable noises from random data.
Thanks for the replies. I did have to replace two leaky Jamicon-brand caps at the outputs years ago, and I'm thinking I may need to go in again and check for more problems or just do a blanket re-cap. MF also mentioned something to me about having problems with some relays they used, but they were very unpleasant on the phone on the one time I was actually able to reach someone. As far as I've ever been able to tell, MF's approach to support and service is "Go away, and don't bother us."
I also found this thread via Google even though diyaudio's own search engine didn't reveal it:
https://www.diyaudio.com/community/threads/musical-fidelity-a3-24-dac-mute-mod.311942/
https://www.diyaudio.com/community/threads/musical-fidelity-a3-24-dac-mute-mod.311942/