DSP: Granular bit depth control with dither

I think it would be great if Roon offered more granular bit depth control and different dithering options in their DSP engine.

18 bit and 20 bit Schiit DACs as a use scenario.

And the benefit would be?


The difference between 24-bit without noise shaping and 20-bit with noise shaping is spurious peaks reaching to -140 dB, compared to the noise floor of -160 dB?
Jeez, man. This is what keeps you up at night?
140 dB is about 24 bits.
Do you have content with 24 bits?
And do you have a room with 140 dB DR? Where do you live?
And do you have electronics with 140 dB DR? Stereophile tested the Benchmark AHB2 amp at 130 dB, or 21 bits, and called it the quietest amp they had ever tested, and said this was right at the limit of what their measurement gear could see.
And are your ears 140 dB capable?

I was in the belief that devices that report their bit depth correctly, also received the reported bit depth. Is this not right?

What additional dithering options are needed?

Not at all.

I don’t know for a fact, but I always interpreted this as referring to the standard bit depths commonly used, such as 16, 24 and 32.
This is about a DAC that is designed so it behaves best with 20 bits?

Although Jussi’s post is not clear, it mixes in noise shaping and I can imagine the difference is really the noise shaping, since 20 bits by itself does not give 160 dB.

They accept 24 bit but round down to 20bit or 18bit internally.

Probably none, Jussi offers different dither options in HQPlayer, he prefers different methods based on sample rate.

So basically you need a workaround for faulty devices that advertise false bit depth and don’t apply dither when down-sampling later on.

Ah no, they just round down - no down-sampling at all. Maybe Roon can just update their device DB (no longer sending 24 bits to these devices)?

I don’t need anything. I could use my HQPlayer license if I absolutely needed it.

Just a nice to have feature request.

This isn’t directed at the OP, but it seems the ability to tweak the sound is an attractive feature to sell products. I’m using AudioOptimizer now. There are all kinds of different options, filters, etc. For a lot of these you are directed to “use what sounds best”. So if one is truly ‘correct’ all the others are different versions of ‘not correct’. They are somehow imparting euphonic distortion
But we audiophiles like to tweak.

Well in this case it does make a measurable difference in certain DACs. If it’s audible or affects audible frequencies is very questionable. In that way this request is a little different than some other subjective audiophile feature requests.