DDL/Dolby Passthrough not splitting channels at all correctly (AC3 etc)

Submitted by itismeguy on Thu, 2007-09-13 07:05.

I've sent this off to support as well, but in case it is easier or someone in the community knows some kind of trick that is not immediately apparent:

I've bought a Sondigo Callisto and unfortunately the passthrough mode just doesn't work. I've got a Yamaha 7.1 DTS/DD reciever connected via SPDIF. I've configured the device using the drivers from this website.

I have tried a number of test files including DD5.1 codec testing files from Dolby (AC3).

When playing with DDL configured and the Sondigo as the default playback device, front right and front left channels are allright, center channel is mixed between left and right, and the rear left and rear right channels are passed to front left and right respectively.

The amp correctly identifies 5.1 channel input but the Sondigo device does not appear to correctly split the channels or conduct passthrough.

Is there a way to enable or force passthrough for AC3 surround sound? Or to force the Sondigo to split the sound correctly?

A dolby digital test file can be downloaded from this location:
http://www.lynnepublishing.com/surround/www_lynnemusic_com_surround_test...

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Seems to me your playback

Submitted by mini on Thu, 2007-09-13 08:30.

Seems to me your playback software does not do passthrough, but stereo decoding of the AC3 files. The driver then does upmixing to 5.1 and DDL encoding. What's the software you are using?

Also, you don't want DDL to kick in at all in this case. You want AC3 passthrough.

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Software

Submitted by itismeguy on Thu, 2007-09-13 12:18.

Awesome! Using a variety of different players, I've gotten some results.

Comparing it to the analog outs from my main PC here and the optical out from the Xbox I have running XBMC, I can see the channel separation is working after a fashion, but there's two problems:

1) A noticeable delay on the rear channels
2) The rear/side left and rear/side right surrounds are transposed if I choose 5.1 configuration
3) If I choose 7.1 within Windows and 8 channels within Sondigo's software, it plays the rear surrounds transposed, and it plays the very rear channels through the main speakers - also, my amp still only detects 5.1 input.

Is there a way to switch the left and right channels on the Callisto?

Edit: Also, the rear channels are really very quiet compared to my DVD player, TV tuner, Xbox and PC (so I am guessing this is another Callisto problem). Can the rear audio be boosted?

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Levels and Delays

Submitted by Len on Tue, 2007-09-25 20:40.

The level of the surround channels relative to the front channels is set by the playback software or the decoder, not in the Callisto driver, unless you have made adjustments to them in the control panel.

There should also not be any more delay introduced by the Callisto than the XBOX -- but you will definitely need to ensure that any pre-encoded Dolby Digital/DTS content (i.e. DVDs) is being passed through rather than decoded and then re-encoded. The media player should have a "enable digital out" mode.

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