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Can you review a Synchro-Mesh S/PDIF re-clocker?

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Alisterkoran

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I'm looking forward to measurements showing a 10X improvement in jitter with Synchromesh, especially at the output of a DAC.
Sadly that won't be possible. He says he doesn't think the AP system is resolving enough or uses the right measurements. So if Amir does do some measurements and doesn't see the 10x improvement, it means his test equipment isn't good enough. . . .

I run into lots of skeptics on all of the forums. I'm used to it.
That's a coincidence, the same thing happens to me on athletic forums . . .
 

svart-hvitt

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@Empirical Audio , remember to send your Dynamo LPS, reference cables etc. too. We don’t want to leave any stones unturned here.

BTW, here’s a review with measurements of two other reclockers from Mutec and Lake People (they do a lot more than reclocking):

https://www.stereo.de/archiv/archiv/download///67345/

Mutec jitter was measured at 1.2-1.8 nanoseconds. Lake People at 2-4 nanoseconds. And these boxes do a lot more, like conversions of formats and sample rates.

Another Mutec test with J tests:

https://www.lowbeats.de/test-mutec-mc-3-wordclock-generator/

So I look forward to reading the review!

EDIT1: A Paul Miller take on Mutec reclocking: https://www.mutec-net.com/downloads/manuals/MUTEC_MC-3plusUSB_-_HFN.pdf

EDIT2: A Mutec reclocker test with files for listening comparison tests! https://www.bonedo.de/artikel/einzelansicht/mutec-mc-3-smart-clock-usb-und-ref10-test.html
 
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Sir Sanders Zingmore

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Me too. I hear the difference it makes on all sources, but it will be interesting to see if the analog measurement technology is up to the task. In the past, I have read numerous reviews in Stereophile where the reviewer raves about the SQ and yet JA measurements don't reflect this. I have also read multiple reviews by JA where he tries to correlate some measurement to the sound quality of a digital cable, usually S/PDIF or USB. He can never see any difference in the measurements and yet the cables definitely sound different. I don't think the AP system is resolving enough or uses the right measurements to accomplish this. IMO, the measurement technology and input stimulus needs to be improved for analog measurements.

Welcome Steve. Nice to have you on board.
I have read glowing reviews of your products on other forums.

I do wonder what you expect to come out of Amir’s measurements.
As I see it, there are 3 possible outcomes.
1. The measurements show no effect at all
2. Your device degrades the measurements.
3. Your device improves the measurements.

Can you tell us what you will conclude in each of the above scenarios?
 
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Empirical Audio

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If it's on the internet, it must be true ;)

I'm looking forward to measurements showing a 10X improvement in jitter with Synchromesh, especially at the output of a DAC.

Me too. I hope the measurement system is up to it. If it is, it should show 100X improvement over the typical transport.

BTW, you don't need the internet to prove that Taccola invented many of the things that Leonardo is attributed with before he was even born. Just look at Taccola's drawings.


Steve N.
 
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"@Empirical Audio , remember to send your Dynamo LPS, reference cables etc. too. We don’t want to leave any stones unturned here.

BTW, here’s a review with measurements of two other reclockers from Mutec and Lake People (they do a lot more than reclocking):

https://www.stereo.de/archiv/archiv/download///67345/"

I looked at this device, although I cannot read Deutsch. The output waveform, if that is what is shown on the scope, has a very slow risetime. This will result in much higher jitter. My products have a risetime of ~400psec.

I will definitely send all of the accessories for the measurements. I would also like to see if it makes any difference to have different sources feeding it or different input cables.

Steve N.
 
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Welcome Steve. Nice to have you on board.
I have read glowing reviews of your products on other forums.

I do wonder what you expect to come out of Amir’s measurements.
As I see it, there are 3 possible outcomes.

1. The measurements show no effect at all

This depends on the measurement method. If only using a DAC to look at jitter, then he is using the wrong DAC. I requested that he use a DAC with resampling on the inputs and one without. I would like to see measurements with and without a DAC.

The other issue is relative scale of the jitter. If one believes that very small differences in jitter are inaudible, then the wrong conclusion may be reached. Like I said previously, a small change in jitter, from 22psec to 7psec was immediately obvious to me using my system and in my measurements. If the playback system used is not resolving enough or the noise level too high, then these differences may not be audible.

2. Your device degrades the measurements.

That would be a shocker. Given that this is my most popular product in 22 years and I have never had ANY negative review, I would have to blame the measurement system or techniques for not correlating to the audio result. My re-clocker outputs very fast edges, around 400 psec. This is why I usually insist on using my 16GHz aerospace quality silver cable from the output to the termination. If the measurement system cannot properly terminate to a signal this fast, it may cause problems in the measurement. The AP system is the world standard, so I believe this is unlikely.

3. Your device improves the measurements.

I would expect this, although I am frankly dubious about the measurement technique. I did notice that my measurements on the iFi SPDIF iPurifier correlate pretty closely with Amir's, so that is reassuring:

https://www.audiocircle.com/index.php?topic=157348.20

Steve N.
 

svart-hvitt

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"@Empirical Audio , remember to send your Dynamo LPS, reference cables etc. too. We don’t want to leave any stones unturned here.

BTW, here’s a review with measurements of two other reclockers from Mutec and Lake People (they do a lot more than reclocking):

https://www.stereo.de/archiv/archiv/download///67345/"

I looked at this device, although I cannot read Deutsch. The output waveform, if that is what is shown on the scope, has a very slow risetime. This will result in much higher jitter. My products have a risetime of ~400psec.

I will definitely send all of the accessories for the measurements. I would also like to see if it makes any difference to have different sources feeding it or different input cables.

Steve N.

Steve, use Google to translate. Open PDF in Word if you find it difficult to copy from PDF.

Here’s an English marketing text from Mutec with measurements from Lowbeats.de embedded:

https://www.mutec-net.com/product_mc-3-plus-usb.php#description

PLEASE NOTE! The measurements I showed can be replicated by @amirm to document any benefits or degrading. In other words: Measurements will show effects, we just don’t know which, the level of effects and if they’re inside audible band.
 

amirm

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Before a war breaks out..... :)

Steve, we are guided by audio science here. Please don't make strong subjective comments that are not backed by controlled testing.

Members, Steve has very good technical design knowledge. Having him around would be good. So please don't go for full strangulation. :)
 
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In terms of lowest jitter, this device from Mutec claims to have a world record (maybe MSB claims the same top spot too but I don’t know if it’s based on public measurements):

https://www.mutec-net.com/product_ref_10.php

See phase noise data in the manual, see page 16:

https://www.mutec-net.com/downloads/manuals/MUTEC_REF_10_Manual_V1_E_screen.pdf

Any comments, @Empirical Audio ?

Very low for sure, but this is their 10MHz oscillator without any cable attached.

We are talking about S/PDIF data jitter at the end of a 1.25m cable. A totally different animal.

Steve N.
 

svart-hvitt

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Very low for sure, but this is their 10MHz oscillator without any cable attached.

We are talking about S/PDIF data jitter at the end of a 1.25m cable. A totally different animal.

Steve N.

Thanks!

I look forward to seeing @amirm ’s measurements here.
 

Killingbeans

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There's a lot of things in this thread that makes me wish I had more than two eyebrows to raise.

But I don't really have neither the desire nor the intellectual firepower to start a war. I'll just get some popcorn ready and keep my fingers crossed for not needing them :D
 
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RayDunzl

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I don't think the AP system is resolving enough

It claims (from what I just read) 24 bit resolution, so 144dB.

That, according to the Shoutometer is the theoretical back-of-the-napkin difference between someone shouting at you from 1 meter and somebody else shouting at you from 10,425 miles/16,777km.

Seems like that should be pretty close to enough resolution.

Of course, it measures the wrong things to be useful, but still...
 

restorer-john

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You presume wrong. It uses a 4192 re-sampler chip.

Wow.

Wasn't it circa 2005 (14 years ago) when the Cirrus/Crystal CS-8421 was released with way better specs in every regard than the SR-8192?

SR-8192:

1552260350053.png


CS-8421:
1552260449095.png
 

amirm

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It claims (from what I just read) 24 bit resolution, so 144dB.
We get dig into the noise floor using FFT to below -160 dB easily. Here is the loopback test on the AP, measuring the performance of its own generator:
Audio Precision APx555 Dashboard.png


Two distortion spikes at -148 and -150 dB are clearly visible. And this is with 32K FFT. We can go to one million if needed.

AP has a jitter analyzer and that analyzer is limited in performance. "Inferred jitter" using FFT is not.
 

FrantzM

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Hi

I am quietly waiting for the measurements... I found the veiled intonation that : "perhaps" or "If "(or whatever modifier was used) "the AP" is of sufficient resolution of whatever word was used ... unsettling.
As they say , we'll see... Until then, allow me to be incredulous.
 
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Empirical Audio

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It claims (from what I just read) 24 bit resolution, so 144dB.

That, according to the Shoutometer is the theoretical back-of-the-napkin difference between someone shouting at you from 1 meter and somebody else shouting at you from 10,425 miles/16,777km.

Seems like that should be pretty close to enough resolution.

Of course, it measures the wrong things to be useful, but still...

It's fine for analog measurements. It's the digital that is in question. The problem I have with most analog measurements is they don't use real music for stimulus and they don't look for dynamic response. An impulse response measurement is insufficient IMO. Steady-state is interesting, but even the cheapest components usually get this right. Dynamics is the issue with most inexpensive gear. Transistor non-linearity with load, changing signal amplitude and dynamic signals is what the measurements should focus on. This is what sets really good components apart from mid-fi IME. This is more about the measurement stimulus and process rather than the AP equipment. I'm sure it's up to this task.

For a designer, good sounding audio components is almost always about power delivery, although there are aspects of jitter that require clever circuit design that are digital specific. Power delivery is different than power supply. Power delivery is about delivering the di/dt transient currents to the active devices and chips when they need it without the voltage sagging locally. It's about delivering power to one device and not having the transient currents affect the other local devices. Like achieving low-jitter, this is really an art-form. It involves careful placement of the right types and sizes of decoupling caps. It involves designing discrete regulators that are very fast responding and low-noise. It involves layout of the circuit board so that crosstalk and power hogging is avoided. Unfortunately, none of these things is taught in college. Maybe someday I will teach it if I live in a urban setting....

Steve N.
 
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