What is "24 bit fixed-point padded to 32 bits"?

[mshan]

What exactly is "24 bit fixed-point padded to 32 bits" and what is it supposed to do?

 

[Iron_Dreamer]

Well, it outputs 24 actual bits of sound data, but puts it in 32-bit chunks, because often soundcards with 24-bit dacs only have 16 and 32 bit modes to work in (like the RME), so if you want to use the full 24-bit capability of the dac, you must trick the card by sending it 24-bit padded to 32.

 

[lan]

The driver deals with 16 and 32 not 24 so that's why you must pad it. Padding means adding 0s. A 24bit DAC takes 24bits of input and gets rid of the extra 8 zeros.

 

[Haribo]

So if I want my 44.1/16 music to be as unaffected as possible in foobar2k, and my ASIO driver only accepts 32bit output, I should chose 16bit padded to 32bit?

 

[mshan]

Also, is padding supposed to improve sound quality or is it simply a trick to make foobar function properly with various sound cards?

 

[lan]

Quote:

Originally Posted by Haribo So if I want my 44.1/16 music to be as unaffected as possible in foobar2k, and my ASIO driver only accepts 32bit output, I should chose 16bit padded to 32bit?

If it works, go for it.

Quote:

Originally Posted by mshan Also, is padding supposed to improve sound quality or is it simply a trick to make foobar function properly with various sound cards?

Nothing to do with sound quality. I think it makes things work with ASIO mainly. I don't think the other output methods complain.

 

[Duncan]

It puzzles me too, seeing that the au2 is promoted as a 24 bit DAC, yet I use 32bit fixed point mode in foobar, and it works great using KS...

 

[RunsWithScissors]

The thing to keep in mind is that you don't get any additional increase in precision so the sound quality is still limited to what 24 bits will provide. Padding up to 32 bits with zeros does not actually add actual sound information, just zeros to make the data format compatible with the output device.

 

[Edwood]

My RME PAD only works with ASIO with 24 padded to 32 or 32 fixed.

Also, multiple RME's in one computer only works with Waveout.

-Ed

 

[Orpheus]

well, i dunno how it's applied to your soundcard... but when you're doing lots of processing, internal 32-bit processing can help with generation loss. that is, as you apply more and more effects, you are able to save a couple more bits of information ultimately. but if you're just talking about your driver... yeah, it's probably more for compatibility purposes.