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

[MZKM]

When I used to sell cables, I didn't even know about this study. Nobody contacted me. The thing that these guys don't get is that high-frequency effects on a speaker cable are not in themselves audible, however the reflections on the cable without a terminator can change the behavior/linearity of the amplifier output drivers. This is what causes changes in the audio frequencies. It's an indirect effect.

They also compare my termination to a Zoebel network. It is not the same thing. This is a transmission-line termination, not a Zoebel. The Zoebel is essentially a filter. The transmission-line termination is tuned to the cable.

Steve N.

You thought Audioholics asked for a sample of your product to give a subjective review?

Nobody contacted me.

They used your cable and have your reply (similar to the one you just gave) as part of the article as well. Are you saying they didn't ask for a sample but simply shelled out $700+ and returned it when they were done?

however the reflections on the cable without a terminator can change the behavior/linearity of the amplifier output drivers. This is what causes changes in the audio frequencies. It's an indirect effect.

The Axiom Audio cable is terminated, and its performance is near identical to yours.

 

[RayDunzl]

This forum is scientifically oriented, so either propose how your product should be meausured or stop talking nonsense.

Isn't empirical planning on sending a unit to @amirm for scientifical measurement?

I tend to talk nonsense, when continually provoked.

I'd view it as a common defense mechanism.

 

[SIY]

Not good enough. You need to understand every microsecond of the left and right channel tracks and compare them on the fly to the ideal track. Any variation is distortion.

Well, I'll ask again: what specifically is a suitable test signal and analysis to demonstrate the "interplay" that you have claimed?

 

[KSTR]

Interplay is the effect of both channels playing a certain pattern that is different from left to right. This will have an effect on the measurement and an effect on the component being measured. Certainly there will be an effect on the component because the power subsystem will be delivering different transient currents to the left and the right channels at the same moment. If this effect can degrade the waveform of either channel, then this would be detected in the measurement system if it were looking for this effect synchronously in both channels.

Here are examples:
If you are only playing a stimulus track through one channel, this is not sufficient. If you are playing the same track through both channels, this is not sufficient. If you are playing different track through left and right channels, but you are only looking at one channel at a time for degradation in the waveform, you may miss degradation in the other channel. This is a lot like intermodulation distortion, but the stimulus and the measurement process must be designed to look for this.

Here a somewhat related measurement with the RME Adi-2 Pro FS. I applied a current pulse by shorting the Headphones(3/4) output of the device while it reproduces a short full-scale peak. The short duration of the pulse (actually a doublet to exite both rails) doesn't trigger the overcurrent sensing, hence almost the full short-circuit current of 3 OPA1688's is produced, about 0.5A(!) total.
I measured the feed-through from this to the main output(1/2) (which is feed from a seperate AK4490, so this isn't normal channel crosstalk) while it is outputting -6dBFS DC (the Adi-2 Pro can output DC) which is blocked by coupling input cap of the ADC. ADC runs with 20dB gain so it's influence should be minimal. Heavy block averaging was used to dig down in the noise (~40dB reduction). Because the symptom is strictly signal-correlated there is no loss of information by the block averaging.

The error from this rather exteme (completely unrealistic in normal use) shock-exiting the supply rails only amounts to about +-6 LSB's ref. DAC output range (not visible in the non-averaged waveform, still below noise floor).

This is a most excellent result. I don't see any chance that the crosstalk you're talking about is any significant, given the low currents. I might try what you suggest, testing L/R channels, with even more noise reduction (50...60dB can be achieved which is equivalent to 28...30 bit equivalent resolution, it just takes some very significant measurement time) but I don't expect to find anything....

 

[garbulky]

Absolutely it can be measured. Now quit harassing me.

Your proposed measurements are not in the standard testing suite Amir or ja performs. If you want him to deviate to something that makes sense to you, you should spell it out. Your current description sounds too vague. And when other people take a guess, you tell them it was the wrong way. So clearly, your description isn’t sufficient Make it clearer otherwise it’s a waste of time on both ends.

 

[Krunok]

Isn't empirical planning on sending a unit to @amirm for scientifical measurement?

I tend to talk nonsense, when continually provoked.

I'd view it as a common defense mechanism.

It is. But if you say in advance measurements won't be valid than your intentions should be questioned.
I'm not provoking him, I'm simply asking how he proposes his device is measured.

IMHO only kids are allowed to use "talking nonsense" as defence mechanism - adults should use counter arguments. Any particular reason why you're advocating for him?

 

[Sir Sanders Zingmore]

Your proposed measurements are not in the standard testing suite Amir or ja performs. If you want him to deviate to something that makes sense to you, you should spell it out. Your current description sounds too vague. And when other people take a guess, you tell them it was the wrong way. So clearly, your description isn’t sufficient Make it clearer otherwise it’s a waste of time on both ends.

Actually rather than being a waste of time, It’s an important investment of time.
It’s carefully setting the groundwork for the get out of jail card in case Amir’s measurements show no improvement (or even a degradation) from the device

 

[Empirical Audio]

I did propose it. Did you read it?

 

[Empirical Audio]

Actually rather than being a waste of time, It’s an important investment of time.
It’s carefully setting the groundwork for the get out of jail card in case Amir’s measurements show no improvement (or even a degradation) from the device

It's called Plausible Deniability. Learned it from an expert, Trump.

 

[SIY]

I've seen some vague stuff, but nothing specific. I don't have your gadget on hand, but I can certainly run specific tests on plain vanilla DACs to get a baseline IF you can specifically say what your proposed test signal is and how the results should be interpreted.

 

[Krunok]

I did propose it. Did you read it?

Are you referring to this?

"You need to understand every microsecond of the left and right channel tracks and compare them on the fly to the ideal track. Any variation is distortion. "

 

[mansr]

I tried to visit the Empirical Audio website, only to be presented with this:

 

[Krunok]

I tried to visit the Empirical Audio website, only to be presented with this:
View attachment 23398

Yep, no https on that site, only unsecure connection can be made.

 

[mansr]

Yep, no https on that site, only unsecure connection can be made.

Oh, the server has https enabled, just with a bad certificate. A Google search for the name returns the https site as the top result:

 

[Xulonn]

The expectation of subjective claims like the ones made in this thread are what convinced me to use my current avatar...

 

[bennetng]

Oh, the server has https enabled, just with a bad certificate. A Google search for the name returns the https site as the top result:
View attachment 23399

I use Firefox as well, no problem visiting the site.

 

[Veri]

I use Firefox as well, no problem visiting the site.
View attachment 23400

Deceptive site LOL I applaud your attempt at humor

@Empirical Audio I suggest a little break/time-out, beside the "harsh" reception most of us are really looking forward to the report on your products!! Hope amir gets some in his hands.

 

[Empirical Audio]

You thought Audioholics asked for a sample of your product to give a subjective review?



They used your cable and have your reply (similar to the one you just gave) as part of the article as well. Are you saying they didn't ask for a sample but simply shelled out $700+ and returned it when they were done?



The Axiom Audio cable is terminated, and its performance is near identical to yours.

I guess the Alzheimers is kicking in...

 

[Krunok]

I guess the Alzheimers is kicking in...

Pathetic. To some point even insulting.

 

[Empirical Audio]

Your proposed measurements are not in the standard testing suite Amir or ja performs. If you want him to deviate to something that makes sense to you, you should spell it out. Your current description sounds too vague. And when other people take a guess, you tell them it was the wrong way. So clearly, your description isn’t sufficient Make it clearer otherwise it’s a waste of time on both ends.

To do what I need, they will need a fully automated measurement system that uses real audio data for stimulus and compares both channels to a reference signal. I don't believe this exists yet. Somebody prove me wrong.