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j.wales
2007-11-15, 18:46
After a few weeks of frustration from dealing with a "pausing" in my music and trying everything under the sun, I think I may have found the issue.

I called Lavry, and they told me that the SB3 was operating outside of the tolerances for the Lavry while it is in crystal lock mode and therefore the Lavry was cutting out the music and not the SB3. The fix, I was told, is to use the Lavry in wide mode.

Now I am not an engineer, but this seems reasonable. Any insight from other more technical oriented people - is this possible? and is it the SB3 not being consistent enough?

Has anyone else experienced this? If so, other fix suggestions?

seanadams
2007-11-15, 19:37
It's hard to say, not knowing exactly how Lavry's design works, but I know lots of people use SB3 with his DACS without issue. I suppose you could have a crystal physically out of tolerance (in either device). That's not something you can readily test without specialized equipment. Have you tried the DAC with other sources?

j.wales
2007-11-15, 20:00
I have not had a chance to test it with another component. I have tried to operate the Lavry in wide mode, and it has not had the issue for about an hour of listening. I plan to do a more in depth test either tomorrow evening or over the weekend, including with another source.

One thing I did do was plug headphones directly into the SB3 and let the digital signal go through the Lavry in Crystal. I had the headphones in one ear and listened to the stereo with the other. When the signal through the Lavry pausd, the headphone signal did not. This is what made me call Lavry. I thought I was going to have to send the Lavry back.

As an FYI, Lavry tech support said that they have had calls like this in the past, tech support new exactly what I was talking about, almost without me finishing. They also recommended that I test with another component to make sure.

KeithL
2007-11-15, 23:21
When I was using a Derek Shek dac, it would crackle and spit occasionally. An email to Derek Shek solved the problem. The music was saved at 48.000 khz instead of 44.100 khz. It's been perfect since I changed to 44.100 khz.
ATB Keith

j.wales
2007-11-16, 05:51
Keith - I did double check - All music is 44.1

That said - if the Lavry can "lock" onto 48Khz - why would this be an issue?

slwiser
2007-11-16, 08:56
CrystalLock assumes a signal of 44.1 khz within 10 ppm, while narrow lets that range out to 100 ppm. Wide lets it go where-ever it will and lock onto the signal. So if they say the SB3 is operating outside its range of what it can lock onto then what they are saying is that the SB3 signal is a little more than 44.11 or less than 44.09 khz. So a very stable clock is needed for the CrystalLock to lock onto. CrystalLock can also lock onto 48khz as well but within those parameters noted. Try narrow first before going to Wide mode. I have read where a lot of people prefer the wide mode instead of either of the others. I am not one of them. The wide mode is much more like what the Benchmark DAC1 does.

I was a little off above, here is the message I remembered from the Lavry Forums on Dealing with signal drops (DA10) -- suggestions needed:
----------------------------------
The CrystalLock™ circuit in the DA-10 has a “capture window” of +100 PPM (parts per million) which exceeds the specification for the AES interface standard. The actual capture range typically exceeds this spec in production units.

If your DA-10 is losing lock in the CrystalLock™ mode, I would suggest trying narrow and wide mode. This would tell you if the signal coming in to the DA-10 is within the capture window, or not. The capture window for narrow is nearly the same as for CrystalLock™ mode. The Wide mode operates in a manner more similar to some of the other DA’s you mention, so it is much more forgiving of input signal timing variations.

Chances are the timing variations that prevent the DA-10 from locking consistently in CrystalLock™ mode are not jitter and would not show up as a buffer under-run problem. They are more likely to be caused by momentary interruptions of the streaming of the audio data caused by software/system timing issues.

I would be curious if anything else changed in your PC, like other hardware or software changes.

If your system does not supply an accurate enough signal for the DA-10 to lock in CrystalLock™ mode, you may need to use Wide mode instead.

If you have a “pure audio” device like a CD player with a digital output, I would suggest using this as a source to see if there is any sign of a problem using the CrystalLock™ mode.

If you have a Tech Support question or problem, in the future please contact me at:
techsupport@lavryengineering.com

seanadams
2007-11-16, 11:04
They are more likely to be caused by momentary interruptions of the streaming of the audio data caused by software/system timing issues.

This comment demonstrates (for a company that makes DACs) either a startlingly poor understanding of how s/pdif works, or a hopeful assumption that Squeezebox must be mysteriously different from any other s/pdif source in the world.

There is nothing that could happen on the data delivery side of things that would affect the timing or any other performance characteristics of the s/pdif output. If Squeezebox can't get data from the server it will simply output digital silence until more data is available. In that respect it behaves exactly the same as a CD player would when it encounters a section of the disc it can't read, or when the user jumps to the next track.

If _I_ were the one admittedly violating the spec, I certainly would not be so quick to blame the other device!

If you'd like, you can send both products to me for testing. I suspect that the mean frequencies of the crystals in each device simply differ by more than the CrystalLock(tm) circuit allows, and that is something I can easily measure here. Of course you could also just send your unit in for a hardware swap, although even if that solves the problem it would not tell us very much.

I would also invite Lavry to participate in this discussion, although I know that on other occasions they have been very cagey about discussing CrystalLock.

slwiser
2007-11-16, 11:42
This comment demonstrates (for a company that makes DACs) either a startlingly poor understanding of how s/pdif works, or a hopeful assumption that Squeezebox must be mysteriously different from any other s/pdif source in the world.



Let me show my ignorance again...Isn't s/pdif simply a signal protocol and like any other signal the basic signal can be interrupted however abruptly? The SB does not talk back and forth with the receiver device no matter what receiver device you use? Right?

If I attempt to understand the Lavry explanation this is what I would think which may be incorrect. The Lavry using CrystalLock reclocks the signal somehow based on it's own clock at 44.1 khz which arguably could itself somehow be off. If the clock feeding the s/pdif signal is not within it proper band expected then the FIFO buffer could get flooded or emptied and problems may occur.

Robin Bowes
2007-11-16, 12:26
slwiser wrote:
> seanadams;243204 Wrote:
>> This comment demonstrates (for a company that makes DACs) either a
>> startlingly poor understanding of how s/pdif works, or a hopeful
>> assumption that Squeezebox must be mysteriously different from any
>> other s/pdif source in the world.
>>
>>
>
> Let me show my ignorance again...Isn't s/pdif simply a signal protocol
> and like any other signal the basic signal can be interrupted however
> abruptly? The SB does not talk back and forth with the receiver device
> no matter what receiver device you use? Right?

What Sean is saying is that the s/pdif output is always on. If there is
no music to send, it just sends silence.

R.

slwiser
2007-11-16, 12:39
What Sean is saying is that the s/pdif output is always on. If there is
no music to send, it just sends silence.

R.

I did not realize that...but then that does not make any sense to me in context.

j.wales
2007-11-17, 06:45
Sean

I have hooked up the Lavry to a CD player, and there are a couple of notes. One- and most puzzling to me is that the Crystal Lock on the DA 10 is on 88.2-I was under the impression that all CDs output at 44.1 unless HD - I did not think the CD player was upsampling - It is a $125 Panasonic F87 5 disc CD/DVD player. It does play HDCDs, but none of the CDs I am playing are HD. Why would this be?

That said, there have not been any pauses for several hours of listening between last night and this morning. Does this mean it is a tolerance difference between the SB3 and the DA 10? 2. Now this may show my ignorance, but can this be caused by environmental factors? ie RF/EMI noise? Temp? etc. Finally what is the fix? Something just does not seem right about having to use the DA-10 at a less than ideal setting.

mephisto
2007-11-17, 07:18
Hi 'j'

I've been using a Lavry DA10 with my SB3 for over 18 months with no problems whatsoever, so I don't think there's anything intrinsically wrong with the combination. Are you sure the Lavry is losing lock? If it is you would see the lock light go out during the pauses. If the lock light remains illuminated I would think that indicates a problem with data streaming via the SB3.

Keith.

slwiser
2007-11-17, 07:41
I have had my Lavry DA10 since Apr 06 and have a few drop out problems but changing sources and cables fix all those. Now that microwave door when it shuts hard just kicks up some big time AC issues for me.

j.wales
2007-11-17, 08:57
Keith

I don't think there is anything intrinsically wrong with the set up - I actually put the combination together based partially on what I read on these forums - I know there are many happy listeners out there with the DA 10/SB3 combo - which is why I am asking about environmental factors - can I do something different before changing hardware.

As for the light - it does not go out. As far as the data - not sure what else to do to test

I have the SB3 hooked up to pre-amp using both analog outputs direct and digital through DA 10. I also have headphones hooked directly into the SB3. The only one that delivers the pause is the digital through the DA 10. SB3 is hooked up using CAT 5 - not wireless - I have used the SB3 at least 6 months before I got the DA 10 using analog outs and never had this issue. I have watched the buffer on the SB3 never goes below 100% on a song.

Slwiser - when you say changing sources - Do you mean as in a CD player versus the SB3 - and what cables have been tried? which worked and was it between the SB3 and the DA 10?

totoro
2007-11-17, 09:05
Keith

I don't think there is anything intrinsically wrong with the set up - I actually put the combination together based partially on what I read on these forums - I know there are many happy listeners out there with the DA 10/SB3 combo - which is why I am asking about environmental factors - can I do something different before changing hardware.

As for the light - it does not go out. As far as the data - not sure what else to do to test

I have the SB3 hooked up to pre-amp using both analog outputs direct and digital through DA 10. I also have headphones hooked directly into the SB3. The only one that delivers the pause is the digital through the DA 10. SB3 is hooked up using CAT 5 - not wireless - I have used the SB3 at least 6 months before I got the DA 10 using analog outs and never had this issue. I have watched the buffer on the SB3 never goes below 100% on a song.

Slwiser - when you say changing sources - Do you mean as in a CD player versus the SB3 - and what cables have been tried? which worked and was it between the SB3 and the DA 10?

Are you using the sb3 in a wireless setup? If so, maybe you're just getting dropouts. This is pretty easily tested. Just omit the lavry for a while. If you still have issues with music stopping, you're probably getting dropouts, and will need to experiment with using different channels on your wireless router.

slwiser
2007-11-17, 09:41
When I say changing sources I mean different computer delivery methods. Old computer with USB challenges vs. new computer. Others have noted cables have made a difference in the Lavry forums.

seanadams
2007-11-18, 01:29
Try a different cable. Video cable is good for s/pdif.

Mark Lanctot
2007-11-18, 14:10
One- and most puzzling to me is that the Crystal Lock on the DA 10 is on 88.2-I was under the impression that all CDs output at 44.1 unless HD - I did not think the CD player was upsampling - It is a $125 Panasonic F87 5 disc CD/DVD player. It does play HDCDs, but none of the CDs I am playing are HD.

Actually HDCDs are 20-bit, 44.1 kHz, not 88.2 kHz.

You can play back HDCDs on an SB provided:

- the SB is connected digitally to an external HDCD decoder

- you are not using any digital volume attentuation

- you are not using ReplayGain

This also, incidentally, proves that the SB is bit-perfect. You alter the bits at all and an HDCD decoder will no longer recognize the source as HDCD.

j.wales
2008-03-15, 07:53
After a few weeks of frustration from dealing with a "pausing" in my music and trying everything under the sun, I think I may have found the issue.

I called Lavry, and they told me that the SB3 was operating outside of the tolerances for the Lavry while it is in crystal lock mode and therefore the Lavry was cutting out the music and not the SB3. The fix, I was told, is to use the Lavry in wide mode.

Now I am not an engineer, but this seems reasonable. Any insight from other more technical oriented people - is this possible? and is it the SB3 not being consistent enough?

Has anyone else experienced this? If so, other fix suggestions?

I figured I would post a follow up to this as it may help others - After testing many wires and talking with Lavry as well as what is above in the forum - in a last ditch effort I returned the DAC to Lavry - they did some extensive testing and were not able to duplicate the issue - until!! an engineer who was using the DAC constantly - built up static electricity by accident and touched the DA-10 - it paused/dropped the signal - it turns out that the unit was very sensitive to static electricity! - they changed the power supply and something else at NO Charge - and sent it back to me- no issue since - I have also been using a anti -static electricity spray -

Thank you all for the help

Anne
2008-03-15, 08:20
Excellent, equipment can be extremely sensitive to this.
Just for the record, never had any issue whatsoever with my Bryston upsampling dac. I run wireless to SB3.