The dithermode ist essentially for sound quality in DSP.
It would be very helpful to set the diterhing-algorithms in DSP-Settings.
E.g. the older mode from Roon 1.7?
I think this makes the most diffent sounding from Roon 1.8
Where was dithering in 1.7 DSP?
Roon Team has changed the dither algo in 1.8.
It sounds different by comparison to 1.7.
Dithering is essential by all DSP-operations for example upsampling. There are several algos and each algo sounds different. I think is would be a good idea to have the choice.
The conversion filters. These had always been in the same place. Had not noticed that the type of filters have been changed. Are you sure?
WHat makes yo uthink the dither algo has changed in 1.8? Never read that.
@brian wrote a while ago that Roon is using TPDF dither in DSP for bit depth reduction.
From the release notes, no idea if this is a different algorithm or just tweaking the existing one:
Audio stack improvements
The audio pipeline in the Roon Core has been optimized to reduce memory traffic and CPU usage. We have also improved the efficiency and mathematical accuracy of the dithering algorithm used for DSP.
Good spot, I missed that.
Nowadays dithering is generally recommended in each and every step where you reduce the resolution of an audio stream. It is easy to show that you get rid of all the “evil” digital artifacts by dithering and the only thing you have to sacrifice is an unimportant tiny rise in the noise floor. But who says dithering is always necessary? Could dither even have negative side effects? In some situations I believe it can!
In Roon software dither is used in the DSP volume control, in the general DSP and in the track or album gain feature which means that you in some situations add dither several times in a row. The noise floor is still extremely low and everything is ok - or? Without dither and without any audio signal you have no activity at all and total silence but with dither activated you have processing activity as well as the dither noise itself all the time - even without any audio signal present…
In a studio environment it is always good practice to use dither because you don’t know for sure what will happen to the signal later on - massive gain for instance - but at the final stage very close to the endpoint of the stream in your listening room the situation suddenly becomes very different because the artifacts of an undithered reduction from say 32 to 24 bit will be completely inaudible. But what if the artifacts from the active dithering process itself has an impact on the character of the perceived sound?
I feel convinced that the sound from my bridge/DAC combination with undithered digital “Device volume” activated has a more clear and open character compared to the Roon “DSP volume” situation with the same attenuation.
I will therefore suggest Roon to add a choice from several flavors of dither and obviously also the possibility to disable dither completely at least in the “DSP volume” section.