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Neil Hastie
2005-02-04, 06:32
Hi Mark,

I think you may have hit a known Squeezebox issue. There have been a number
of reports of high end DACs not working with the SBs.
I have personal experience of problems with the Audio Synthesis DAX-1.
Others have reported the same problem with the Cyrus DAC-X and later model
Audio Synthesis products.

In all cases the DAC will not lock correctly on a raw pcm/FLAC feed from the
server
but will lock quite happily on an MP3 stream.

The reason for this is unclear but my guess is that spec of the SB clock
output is
incompatable with the narrow clock capture windows used by the PLLs in high
end DACs.

Things to try :-
1. Try running with bitrate limiting turned on.
2. Try taking the Monarch filter out and feed the DAC directly.

Let us know how you get on

Cheers

Neil


>My Squeezebox is running fine from its TOSlink output to my B&K pre/pro
>digital in. However, I wanted to try it with a Monarch jitter filter and
>Bel Canto DAC, which I use for my CD player. Neither the optical nor coax
>out on the SB appears to work with this combo, which works flawlessly with
>my CD player. I've set the bitrate to No Limit and turned off the volume
>control in server settings. Any other suggestions as to what might be
>causing this problem?

Mark Schlack
2005-02-04, 16:29
I tried both of your suggestions, to no avail. I tried bitrates high and
low, and nothing worked. I haven't tried mp3, but then again, why would
I want to do a great job on that? It's already compromised. At least I
know it's not just me.

Mark


Neil Hastie wrote:

> Hi Mark,
>
> I think you may have hit a known Squeezebox issue. There have been a
> number
> of reports of high end DACs not working with the SBs.
> I have personal experience of problems with the Audio Synthesis DAX-1.
> Others have reported the same problem with the Cyrus DAC-X and later
> model
> Audio Synthesis products.
>
> In all cases the DAC will not lock correctly on a raw pcm/FLAC feed
> from the server
> but will lock quite happily on an MP3 stream.
>
> The reason for this is unclear but my guess is that spec of the SB
> clock output is
> incompatable with the narrow clock capture windows used by the PLLs in
> high end DACs.
>
> Things to try :-
> 1. Try running with bitrate limiting turned on.
> 2. Try taking the Monarch filter out and feed the DAC directly.
>
> Let us know how you get on
>
> Cheers
>
> Neil
>
>
>> My Squeezebox is running fine from its TOSlink output to my B&K
>> pre/pro digital in. However, I wanted to try it with a Monarch jitter
>> filter and
>> Bel Canto DAC, which I use for my CD player. Neither the optical nor
>> coax out on the SB appears to work with this combo, which works
>> flawlessly with my CD player. I've set the bitrate to No Limit and
>> turned off the volume control in server settings. Any other
>> suggestions as to what might be causing this problem?
>
>
>
>

Triode
2005-02-04, 16:40
There was a discussion a while ago about the squeezebox taking a while to stabilise its frequency when in pcm mode.

You could try setting it playing for a while and then resetting the dac/jitter filter (e.g. power cycle)

I'm interested how you get on with this as I'm about to add an improved dejitter filter to my dac.

Adrian

----- Original Message -----
From: "Mark Schlack" <mschlack (AT) verizon (DOT) net>
To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
Sent: Friday, February 04, 2005 11:29 PM
Subject: [slim] Problems with outboard DAC


>I tried both of your suggestions, to no avail. I tried bitrates high and
> low, and nothing worked. I haven't tried mp3, but then again, why would
> I want to do a great job on that? It's already compromised. At least I
> know it's not just me.
>
> Mark
>
>
> Neil Hastie wrote:
>
>> Hi Mark,
>>
>> I think you may have hit a known Squeezebox issue. There have been a
>> number
>> of reports of high end DACs not working with the SBs.
>> I have personal experience of problems with the Audio Synthesis DAX-1.
>> Others have reported the same problem with the Cyrus DAC-X and later
>> model
>> Audio Synthesis products.
>>
>> In all cases the DAC will not lock correctly on a raw pcm/FLAC feed
>> from the server
>> but will lock quite happily on an MP3 stream.
>>
>> The reason for this is unclear but my guess is that spec of the SB
>> clock output is
>> incompatable with the narrow clock capture windows used by the PLLs in
>> high end DACs.
>>
>> Things to try :-
>> 1. Try running with bitrate limiting turned on.
>> 2. Try taking the Monarch filter out and feed the DAC directly.
>>
>> Let us know how you get on
>>
>> Cheers
>>
>> Neil
>>
>>
>>> My Squeezebox is running fine from its TOSlink output to my B&K
>>> pre/pro digital in. However, I wanted to try it with a Monarch jitter
>>> filter and
>>> Bel Canto DAC, which I use for my CD player. Neither the optical nor
>>> coax out on the SB appears to work with this combo, which works
>>> flawlessly with my CD player. I've set the bitrate to No Limit and
>>> turned off the volume control in server settings. Any other
>>> suggestions as to what might be causing this problem?
>>
>>
>>
>>

Mark Schlack
2005-02-05, 10:47
Thanks for the suggestion, but no luck. Very odd.

Mark

Triode wrote:

> There was a discussion a while ago about the squeezebox taking a while
> to stabilise its frequency when in pcm mode.
> You could try setting it playing for a while and then resetting the
> dac/jitter filter (e.g. power cycle)
> I'm interested how you get on with this as I'm about to add an
> improved dejitter filter to my dac.
>
> Adrian
>
> ----- Original Message ----- From: "Mark Schlack" <mschlack (AT) verizon (DOT) net>
> To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
> Sent: Friday, February 04, 2005 11:29 PM
> Subject: [slim] Problems with outboard DAC
>
>
>> I tried both of your suggestions, to no avail. I tried bitrates high
>> and low, and nothing worked. I haven't tried mp3, but then again, why
>> would I want to do a great job on that? It's already compromised. At
>> least I know it's not just me.
>>
>> Mark
>>
>>
>> Neil Hastie wrote:
>>
>>> Hi Mark,
>>>
>>> I think you may have hit a known Squeezebox issue. There have been a
>>> number
>>> of reports of high end DACs not working with the SBs.
>>> I have personal experience of problems with the Audio Synthesis DAX-1.
>>> Others have reported the same problem with the Cyrus DAC-X and later
>>> model
>>> Audio Synthesis products.
>>>
>>> In all cases the DAC will not lock correctly on a raw pcm/FLAC feed
>>> from the server
>>> but will lock quite happily on an MP3 stream.
>>>
>>> The reason for this is unclear but my guess is that spec of the SB
>>> clock output is
>>> incompatable with the narrow clock capture windows used by the PLLs
>>> in high end DACs.
>>>
>>> Things to try :-
>>> 1. Try running with bitrate limiting turned on.
>>> 2. Try taking the Monarch filter out and feed the DAC directly.
>>>
>>> Let us know how you get on
>>>
>>> Cheers
>>>
>>> Neil
>>>
>>>
>>>> My Squeezebox is running fine from its TOSlink output to my B&K
>>>> pre/pro digital in. However, I wanted to try it with a Monarch
>>>> jitter filter and
>>>> Bel Canto DAC, which I use for my CD player. Neither the optical
>>>> nor coax out on the SB appears to work with this combo, which works
>>>> flawlessly with my CD player. I've set the bitrate to No Limit and
>>>> turned off the volume control in server settings. Any other
>>>> suggestions as to what might be causing this problem?
>>>
>>>
>>>
>>>
>>>

Mark Schlack
2005-02-05, 15:13
Tried another outboard DAC, the Camelot Arthur, and it worked fine. So
there must be some bad mojo between both the Monarcy jitter filter and
the Bel Canto DAC 1.1 and the SB. Slim Devices, what's up with that? Too
bad, the Bel Canto does a really nice job. BTW, the Camelot was more
detailed than the SB, but not by a huge amount. I don't really like the
Camelot's sound anyway -- it's too brittle and detailed in my system --
so it's a hard comparison to make. My server and SB seem to make at
least as good a transport as my Pioneer Elite DV-59AVi, as far as the
digital bitstream that gets delivered to my pre/pro.

Mark


Triode wrote:

> There was a discussion a while ago about the squeezebox taking a while
> to stabilise its frequency when in pcm mode.
> You could try setting it playing for a while and then resetting the
> dac/jitter filter (e.g. power cycle)
> I'm interested how you get on with this as I'm about to add an
> improved dejitter filter to my dac.
>
> Adrian
>
> ----- Original Message ----- From: "Mark Schlack" <mschlack (AT) verizon (DOT) net>
> To: "Slim Devices Discussion" <discuss (AT) lists (DOT) slimdevices.com>
> Sent: Friday, February 04, 2005 11:29 PM
> Subject: [slim] Problems with outboard DAC
>
>
>> I tried both of your suggestions, to no avail. I tried bitrates high
>> and low, and nothing worked. I haven't tried mp3, but then again, why
>> would I want to do a great job on that? It's already compromised. At
>> least I know it's not just me.
>>
>> Mark
>>
>>
>> Neil Hastie wrote:
>>
>>> Hi Mark,
>>>
>>> I think you may have hit a known Squeezebox issue. There have been a
>>> number
>>> of reports of high end DACs not working with the SBs.
>>> I have personal experience of problems with the Audio Synthesis DAX-1.
>>> Others have reported the same problem with the Cyrus DAC-X and later
>>> model
>>> Audio Synthesis products.
>>>
>>> In all cases the DAC will not lock correctly on a raw pcm/FLAC feed
>>> from the server
>>> but will lock quite happily on an MP3 stream.
>>>
>>> The reason for this is unclear but my guess is that spec of the SB
>>> clock output is
>>> incompatable with the narrow clock capture windows used by the PLLs
>>> in high end DACs.
>>>
>>> Things to try :-
>>> 1. Try running with bitrate limiting turned on.
>>> 2. Try taking the Monarch filter out and feed the DAC directly.
>>>
>>> Let us know how you get on
>>>
>>> Cheers
>>>
>>> Neil
>>>
>>>
>>>> My Squeezebox is running fine from its TOSlink output to my B&K
>>>> pre/pro digital in. However, I wanted to try it with a Monarch
>>>> jitter filter and
>>>> Bel Canto DAC, which I use for my CD player. Neither the optical
>>>> nor coax out on the SB appears to work with this combo, which works
>>>> flawlessly with my CD player. I've set the bitrate to No Limit and
>>>> turned off the volume control in server settings. Any other
>>>> suggestions as to what might be causing this problem?
>>>
>>>
>>>
>>>
>>>

freelunch
2006-01-12, 08:48
Has this issue been further investigated or resolved?

Ironically, when I bought my sb3's, it was with the intention of acquiring a Bel Canto (or similar DAC) to use with it.

julian2002
2006-01-12, 08:57
as far as i know this was ONLY an issue with the original squeezebox 1 and pcm. the chip used to process pcm (as opposed to mp3) was an off the shelf unit which had abysmal specs for timing - it wasn;t capable of keeping a true 44.1khz clock rate but wobbled around it - various software fixes were tried but none worked as it was in the chips firmware whcih couldn;t be changed.
i use an audio synthesis dac and had really bad quality problems (it locked, but badly) however moving to a sb2 COMPLETELY solved the problem. i also tried various 'jitter busters' with no real results (monarchy amd bheringer solutions).
i'm pretty confident that an sb2 or 3 would work fine with one of the dacs mentioned.
cheers


julian

Heuer
2006-01-12, 12:35
My SB3 runs into an Audio Synthesis DAX Discrete and the results are very good indeed. Locks on to 44.1khz, upsamples and is off. Never had any problem.

seanadams
2006-01-12, 20:50
Which model do you have?

SB3: No known issues with the s/pdif - by now the implementation has been extensively proven and I would be very surprised if there are any bugs.

SB2: very early units may have an impedance match problem on the coax output, but this was fixed around April.

SB1: there are some unresolved issues concerning clock precision and channel/polarity inversion.

freelunch
2006-01-18, 10:12
That's great news. Thanks for the update!

Does the channel swapping problem with digi out still exist in the sb3?