Recommendation for DAC needed.

@shadorne 
 
Digital volume control is only an issue with 16Bit DACs, 24Bit should be not audibly difference than analog volume controls, and for sure 32Bit.

@mzkmxcv  

It doesn’t matter how many bits. The problem is at the analog conversion stage. The analog signal will become so small as to drop close to the noise floor of the output stage of the DAC. An analog volume control reduces both signal and noise together. A digital volume control only reduces the signal level.

@shadorne

A 32Bit DAC will have a noise floor of ~ -192dBFS. Meaning even if you turn the volume down from full scale to -40dBFS (much quieter than what we listen at), then the noise floor has risen to -152dBFS, still better than 24Bit.

Like I said, it’s a non-issue with 32Bit.

Its even more of a non-issue with say an ESS 9038, which has access to its internal pathway and decreases the noise floor just like an analog volume control (down until it hits its own noise floor of course). Good DACs have been able to do this for >5yrs.

@mzkmxcv

Noise floor is analog.

There is nothing on the market with an analog noise floor of -192 dBfs. These kind of numbers are utterly meaningless in the real world.

The PS Audio doesn’t have an ESS chip - that some DACs have added analog volume control is indeed wonderful - I was already aware of this so I learned nothing by your comment.

My comment above was about the PS Directstream Sr DAC. Please read comments more carefully before hitting the reply. Analog volume control is not digital volume control. ESS chips that do analog volume adjustment as well as digital is good and I support that because purely digital volume control has limits.

An analog volume control reduces both signal and noise together. A digital volume control only reduces the signal level

You put that out as a statement, not technically in relation to PS Audio, but you did talk about them in the prior sentence, so I can see that.

There is nothing on the market with an analog noise floor of -192 dBfs.

Correct, as the noise floor is reduced due to the performance of the analog components in the DAC. The 32Bit chips on their own are -192dB, as that’s what 32Bit is. The ESS 9038 and AKM 4499 is -140dBFS, and was ~-130dB a few years ago, so slowly progressing forward.

So, even ignoring how they can lower the noise floor with attenuation, if you did the same -40dB attenuation, that would be -100dBFS, still a greter dynamic range than what we have in-room (around 80dB).