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mansr

A case of the jitters

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7 minutes ago, Rt66indierock said:

Please tell me this is an expensive product.

Sorry, it's a Steinberg UR242, retail price $200.

 

5 minutes ago, Ralf11 said:

Please tell me this is an expensive USB cable.

Sorry again, it's a 1.5 m cable that I've forgotten what gadget it came with.

 

40 minutes ago, NOMBEDES said:

Fine.  But can you hear it?

Yes, reliably.

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16 minutes ago, Audiophile Neuroscience said:

@John_Atkinson has anything changed since A case of the Jitters in 2009 ?

Since you bring it up and @John_Atkinson is involved.....

 

The Pioneer universal player is wrongly maligned here. It has horrible jitter worse than shown for 8 seconds then it decreases until 15 seconds and later the jitter is very low. At this point the noise floor drops as well. It does this whenever a track is started or you skip to a new track. So it's only compromised for a few seconds. 

 

Yes I had/have one. I had it as an inexpensive way to play SACDs.

 

https://www.stereophile.com/content/case-jitters-less-cd-quality

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21 minutes ago, John_Atkinson said:

This kind of noisefloor modulation was characteristic of a specific chip set from, IIRC, Finland, that was used in many home theater processors around 10 years ago. See, for example, https://www.stereophile.com/content/lexicon-mc-1-preamplifiersurround-processor-measurements

In the present case, I suspect the clock generator is to blame. There is a single crystal, and the required rates synthesised inside a huge Yamaha DSP chip. The spectrum at the clock input to the converters looks like this:

tek00002.thumb.png.35a2474fd3bbb49af0c70e475d37dd8c.png

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The spectrum is actually of the Steinberg recording the output of a Tektronix AFG. The effects of clock jitter and voltage ripple are of course the same as for a DAC, only in reverse.

 

I also recorded the same signal with a Tascam UH-7000. In a quick ABX test between the two recordings played back on an iFi Nano, I got a perfect 10/10 score without hesitating. The crap in the Steinberg recording is quite apparent.

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4 hours ago, mansr said:

Sorry, it's a Steinberg UR242, retail price $200.

 

Sorry again, it's a 1.5 m cable that I've forgotten what gadget it came with.

 

Yes, reliably.

what does it sound like to you, like a dog barking, rough, ruff?

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Here are the two flac files opened in Soundforge.

Spot the difference quiz on the waveform.

 

image.thumb.png.a27e43b0a2b8c18812c4e6464dfc22a5.png

 

The spectrum analysis reveals the problem.

UR242

image.thumb.png.4913aec1c662fb96d535b9d866997a9a.png

 

Tascam

image.thumb.png.03c044772db7fdb2d57df14c5f4da489.png

 

The clocking could use some work. So what to choose, a jittery output and expensive external clock, or an expensive clock built in.

 

Would be good to sample music through both devices.

 

 

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19 minutes ago, One and a half said:

Here are the two flac files opened in Soundforge.

Spot the difference quiz on the waveform.

 

image.thumb.png.a27e43b0a2b8c18812c4e6464dfc22a5.png

The only thing that screenshot reveals is that the files are not phase aligned. That's unimportant.

 

21 minutes ago, One and a half said:

The clocking could use some work.

Yes, see the spectrum of the actual clock I posted earlier.

 

21 minutes ago, One and a half said:

So what to choose, a jittery output and expensive external clock, or an expensive clock built in.

Huh?

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4 minutes ago, modmix said:

I happend to try a Steinberg UR22mkII recently - looks quite fine to me...

1506191782_UR22mkIIHi-ZHMF25255mVsinus.thumb.jpg.bf0647bbdaf3c06e138ca106834a6d0c.jpg

Signal was taken from Victors 1kHz  (posted by vicnic in DIYaudio thread Low-distortion Audio-range Oscillator).

1015859357_Viktorvicnic-Low-distortionAudio-rangeOscillator-MessungRTX600120dBV20180114.thumb.jpg.590e8c1e4ce5c051e7d6fd34b5d7c376.jpg

 

FYI: I've no relationship to Steinberg.

Try it at 10 kHz.

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