[alsa-devel] Juli@ ICE1724 and 24 bit audio

Pavel Hofman pavel.hofman at insite.cz
Mon Feb 9 21:26:46 CET 2009


Demian Martin napsal(a):
> I have the driver working fine for sample rates from 44.1K to 196K however
> it seems to be truncating the data to 16 bits. I wasn't sure until I started
> testing with the HRx 176.4K 24 bit files that have an embedded HDCD flag in
> the LSB. The files work OK on Windoze systems (with a lot of low level
> settings tweaked) and they play fine but the flag isn't detected by a system
> that can detect them. Further looking at the data stream with a scope it
> seems the last 8 bits aren't changing. Is there anything I can do to control
> the driver to confirm this problem or change the playback settings to make
> it work?
> 
>  

How do you play the files? Do you use the hw or plug:hw device? IIRC, 
the standard-setup dmix resampler is 16-bit only.

I did tests with SPDIF OUT/IN and found it bit-perfect, for 24bit too.

Regular ICE1724 cards do not output 176.4kHz SPDIF, only 88.2kHz. But 
Juli is not affected by that bug.

Regards,


Pavel.


More information about the Alsa-devel mailing list