|
Computer Audio Asylum Music servers and other computer based digital audio technologies. |
For Sale Ads |
Use this form to submit comments directly to the Asylum moderators for this forum. We're particularly interested in truly outstanding posts that might be added to our FAQs.You may also use this form to provide feedback or to call attention to messages that may be in violation of our content rules.
Original Message
Dither
Posted by Roseval on March 14, 2017 at 04:12:27:
PCM audio is integer (16 or 24)
Likewise our DACs only accept integers (16/24/32)
Any type of DSP, be it down-sampling from 24 to 16 or volume control, is a calculation.
There will always be a remainder (1/3=0.3333) and of course this won't fit into a integer.
Unfortunately, this remainder (quantization error) is correlated to the sound.
Say anything below 0.5 set the LSB to 0 and anything above to 1.
To get rid of this; dither is applied before the truncation.
It is a good practice to apply dither anytime DSP is used.If you do "nothing" you are using Windows default (DS)
The audio is send to the mixer, converted to float, dithered and converted back to integer.
If you are using WASAPI, the same will happen.
If you are using WASAPI and "exclusve access" the mixer is bypassed. Hence you get rid of the dither as applied by Win.If you use WASAPI in exclusive mode and all DSP in JRiver is disabled (volume control, DSP studio), you are sending bit perfect data to the DAC.
Bit Perfect Dither is nonsense by design, the moment one apply dither, one is no longer bit perfect.
My guess is , given the strong anti-audiophile sentiment at JRiver, this is their way out for applying dither with 24 bit material.
They probably think it nonsense to do so at -144 dBfs but public demand ask for it.