I'm trying out a cheap r2r DAC from China. Unfortunately it has static noise like a not tuned in radio. If I turn the volume up the sound suddenly at a certain volume becomes clear but the lower volume noise stays. Every instrument and voice above a certain volume is crystal clear but instruments and voices that are lower in volume are really distorted. All at the same time in a song.
Never experienced anything like it before.
Unfortunately there is no schematic available from the manufacturer.
The phenomenon is less with the supplied muse opamp and more so with my discrete ones.
Connected via coaxial cable from my Wiim Ultra feeding a Chip amp with currently no preceding volume pot.
I know it's hard to figure from a distance but maybe someone else had experienced the same phenomenon and figured out how to fix it.
Thanks in advance.
Klaus
Never experienced anything like it before.
Unfortunately there is no schematic available from the manufacturer.
The phenomenon is less with the supplied muse opamp and more so with my discrete ones.
Connected via coaxial cable from my Wiim Ultra feeding a Chip amp with currently no preceding volume pot.
I know it's hard to figure from a distance but maybe someone else had experienced the same phenomenon and figured out how to fix it.
Thanks in advance.
Klaus
In the absence of a schematic, a picture of the board would be a useful start. The volume you're turning up is digital (as you mentioned no volume pot)?
Yes volume control is done by the Wiim Ultra.
It's just a test setup to evaluate the potential of the DAC.
First picture is with Burson opamp fed by onboard 5.4v. I hopped the low voltage would be the cause.
Second picture is with Sparkos Regs+-18v feeding the opamps.
As soon as the music is over the whole rig is silent.
Over the Wiim Ultras internal dac everything works perfectly.
Klaus
abraxalito
By the explanation it sounds like an under biased transistor and when the input reaches a certain level, the trany gets enough to bias it and works. Could be a dry joint?Couldn't do to much measuring since I am in a hotel. I took the setup without the amp with me though and found out that with the headphone the problem is still there but less obvious.
I will put the soldering iron to all joints that are on the active stage and see if it fixes the problem.
Thanks guys for your help.
I will report back.
Klaus
I will put the soldering iron to all joints that are on the active stage and see if it fixes the problem.
Thanks guys for your help.
I will report back.
Klaus
You can try to use the DAC with a different source or amplifier to see if the issue persists.