White noise from DS DAC

Hello!

I have a problem with the DS DAC + Bridge 2 - when there is no audio playing I hear some distinct white noise from the speakers. If I turn the attenuator on - the noise also become quieter but in that mode I have a lack of volume. With other preamps I have there is no noise at all.

My system is: DS DAC - XLR - Pass Labs XA200 monoblocks - Legacy Focus SE.

Where could be the problem?

Also, my DS DAC powers trough 230V-100V transformer because of my power grid different voltage. May be It causes the issue in some way? But other 100V devices works great with this transformer.

Thanks!

Hello @zver_mephi, you mentioned other preamps that you have - do you have one that you could try between the DirectStream DAC and your Pass Labs amps?

If I put the preamp in the chain - the noise almost gone. But I think overall sound quality better without the preamp, maybe because of not so hi-end level of the device.

Is there any solution to eliminate the noise without adding the preamp?

I’ll page @tedsmith for a true expert opinion on what options you have and to cover anything I might miss.

Basically, you’ve encountered an issue with system synergy. Since your speakers are on the more efficient side, you’re able to hear the noise floor on the DSD when you have it on the high output setting.

Putting in the attenuator alleviates this problem, though as you mentioned then you’re not able to get enough gain from the DSD with your amps.

The best way to solve this issue would be with a preamp or passive attenuator.

One other question I have - you mentioned you only hear the white noise when no music is playing. How far away can you hear this noise?

I can hear the noise from my listening position - about 10 ft. to each speaker.