Bug 4479 – 24-bit SPDIF output for adjustable volume and replaygain

Bug 4479 - 24-bit SPDIF output for adjustable volume and replaygain

Summary:

24-bit SPDIF output for adjustable volume and replaygain

Status:	RESOLVED WORKSFORME

Product:	SB 2/3
Classification:	Unclassified
Component:	Audio
Version:	unspecified
Platform:	All All

Importance:	P4 enhancement with 1 vote (vote)
Target Milestone:	---
Assigned To:	Chris Owens

URL:
Keywords:

Depends on:
Blocks:
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Reported:	2006-11-06 12:42 UTC by John Stimson
Modified:	2006-11-13 13:26 UTC (History)
CC List:	0 users

See Also:
Category:	---

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Description John Stimson 2006-11-06 12:42:11 UTC

According to Dan E. at Slim Devices, the SPDIF output of the Squeezebox2 is always 16 bit.  Replaygain and volume adjustments generate 24 bit output for the internal DAC, but that output is dithered or truncated to 16 bit for the SPDIF output.

If it is technically possible I would like to have the option of leaving the volume-adjusted signal at 24 bit resolution for output on the SPDIF port.  I have a 24 bit capable external DAC and would like to use the maximum precision available when using the replaygain feature.

Comment 1 Chris Owens 2006-11-13 13:26:57 UTC

I just got back from chatting with Dan, and he is wiser now.

In fact, the SPDIF output on the SB2 and SB3 is 24 bits, even after replaygain and volume adjustments.

However, you should be aware that many people feel that innacuracies innate in the multiplication of the digital values have an audible affect on the sound, even at 24 bits of resolution.  These people prefer to disable the volume control on the SPDIF output (From the web UI: Player Settings -> Audio -> Digital Volume control) and use an analog level control on the output from their DAC.

Please let me know if there are additional questions, or if you are not actually seeing 24-bit output from your Squeezebox.  There's always the possibility a bug has crept in!