Close in jitter?

[Mivera]

I have read the paper and gone over it a few times to see if I am missing something. The results would appear to be what I had pictured in my mind to start with. Which is exactly why I have great difficulty placing credence in such small levels of close in jitter being audible. Such small differences in timing are not just difficult to measure, I cannot imagine how they would survive above levels of randomness in the air. The differences are simply far too small.

This is why listening is far better than just figuring. Lots of people have a hard time understanding how an AM radio can pickup music from the thin air as well. Just imagine the skeptics back when radio was first invented.

 

[Mivera]

The best way of doing what?

Measuring tbe i2s clocks do not show us the relevant bit of information; the analugue output of tbe dac.

Okay invent a machine that is accurate enough to correlate the jitter that the Microsemi 5125A can pickup right before the DAC chip, in the analog domain after the DAC chip then. Once we have that then perfect. We can now use that machine for this testing. I can imagine there's a machine out there that can do it somewhere. It's just not an APx with the J-test.

 

[March Audio]

I have already demonstrated to my clients that lower jitter can be heard. Even at levels light years beyond what an APx 555 could dream of detecting. And I know the jitter was lower because I did the proper testing with the proper machines.

How do you know the cause of the difference that is allegedly heard is due to jitter?

How did you established cause and effect?

 

[Blumlein 88]

This is why listening is far better than just figuring. Lots of people have a hard time understanding how an AM radio can pickup music from the thin air as well. Just imagine the skeptics back when radio was first invented.

I could have taken an AM radio and any 100 people who could hear. Test them blind and 100 of 100 could tell me if they heard music yes or no correctly.

 

[March Audio]

Okay invent a machine that is accurate enough to correlate the jitter that the Microsemi 5125A can pickup right before the DAC chip, in the analog domain after the DAC chip then. Once we have that then perfect. We can now use that machine for this testing. I can imagine there's a machine out there that can do it somewhere. It's just not an APx with the J-test.

So you are agreeing that jitter seen in the digital domain on the dac input cant be seen in the analogue domain of the dac output.

 

[Mivera]

How do you know the cause of the difference that is allegedly heard us due to jitter?

How did you established cause and effect?

Read Bruno's whitepaper. I just listened to what the very best DAC manufacturers, and clock experts were telling me and conducted my own experiments. It became very clear right away that the low phase noise made a huge difference. So I even did a blind test with Dustin Foreman the Sabre chip head engineer. We soldered a Crystek 950 clock into 1 of the Resonnesence Mirus DAC's, and a 957 into a another. We sent it off to the golden ear guy who does all of the listening tests for Resonessence Labs. We didn't tell him which was which, and let him listen for a week. He could clearly pick out which DAC had the 957. That was just the beginning. I did several more experiments since.

 

[Mivera]

Oh and I forgot to mention. Dustin measured both of those DAC's from the analog outputs at the ESS Sabre lab with the APx-555, and they were identical. Swapping the 950 to the 957 made absolutely no difference to the measurements from the analog outputs. Yet you can clearly see the difference in the phase noise between the 2 clocks:

 

[Mivera]

I also swapped the Crystek 950 in my Exasound E20 with a Crystek 575. The results were so profound that George at Exasound even switched to the 575 for the successor the E22. That was the only difference, yet several people traded up and raved about the upgrade.

 

[Mivera]

Here you can see the successor to the E20, the Exasound E22 with the upgraded Crystek 575 clock. All based on listening tests. Yet absolutely no difference in the specs from the analog outputs.

 

[Mivera]

So you are agreeing that jitter seen in the digital domain on the dac input cant be seen in the analogue domain of the dac output.

Yes I'm agreeing it can't be seen with an APx. Well not the J-test anyways. Perhaps if you got creative with the settings there's a way to do it. But you would also need a machine like the Microsemi 5125A to take the digital domain measurements, and try to make them correlate with the analog measurements. Without both machines you'll have no way to know what to look for.

 

[Mivera]

The clocks we use now in our bottom of the line gear are light years better than the Crystek 575 and 957. And I have every single 1 measured and sorted. Each client gets a plot of the actual clock in his DAC. Clock to clock consistency is extremely poor. Even up to 15dBc/Hz @ 10hz per clock! It took us sorting and measuring 600 of these NDK NZ2520SD's to get just 25 that are better than -111dBc @ 10hz. I had to wait 4 months for just 25 clocks because each one needs to warm up in the test socket for a minimum of 2 hours to take a measurement like this.

 

[Mivera]

Another thing, just like demonstrated with the TI vibration test in the other thread, these clocks are extremely sensitive to vibration. For example even if you blow on the clock while being tested the phase noise spikes and the test is ruined. The clock socket needs to be on an isolation platform in a very still room to get an accurate test.

 

[Nightlord]

Another thing, just like demonstrated with the TI vibration test in the other thread, these clocks are extremely sensitive to vibration. For example even if you blow on the clock while being tested the phase noise spikes and the test is ruined. The clock socket needs to be on an isolation platform in a very still room to get an accurate test.

Very useful when it will be put in a room with loudspeakers playing then...

 

[Cosmik]

I would be fascinated to know how loud the acoustic noise of power supplies (transformer hum, whistling inductors, thermal expansion and contraction of transistors etc.) in the same room as the system is, compared to the noise levels we're talking about here. It isn't zero. The power supply noise will also be modulated by the signal.

 

[amirm]

I just listened to what the very best DAC manufacturers, and clock experts were telling me and conducted my own experiments. It became very clear right away that the low phase noise made a huge difference. So I even did a blind test with Dustin Foreman the Sabre chip head engineer.

Then you would be willing to participate in a blind test conducted by me where you win $5,000 if you can do this but if you fail, I only get my expenses of $500. Yes? You can bring any clock expert that says the same thing about audibility there just the same.

 

[amirm]

I also swapped the Crystek 950 in my Exasound E20 with a Crystek 575. The results were so profound that George at Exasound even switched to the 575 for the successor the E22. That was the only difference, yet several people traded up and raved about the upgrade.

Several people? That is nothing. There are people who sell boxes with dirt in them and have hundreds of if not thousands of people raving about them.

 

[Mivera]

Very useful when it will be put in a room with loudspeakers playing then...

This is why people use isolation platforms under their DAC's. It's not something unique to these clocks.

 

[Mivera]

Then you would be willing to participate in a blind test conducted by me where you win $5,000 if you can do this but if you fail, I only get my expenses of $500. Yes? You can bring any clock expert that says the same thing about audibility there just the same.

First thing to determine is your machine isn't good enough to do the job. After that's clearly established, you can do whatever psychoacoustic testing you want.

 

[Purité Audio]

You would be better off at WBF Mike they believe this sort of stuff over there.
Btw the spare card you sent me did arrive, and the unit does work much more consistently than before, so thanks .
Keith

 

[Mivera]

You would be better off at WBF Mike they believe this sort of stuff over there.
Btw the spare card you sent me did arrive, and the unit does work much more consistently than before, so thanks .
Keith

I thought this forum would be into objective data. Anyways that's good. But there's been quite a bit more improvements with Roon since then as well. So I have an even better OS now if you want a copy. Although if there's no issues no since changing. 80% of my clients are still using the very first version I gave them without any issues. The other 19% only updated because I sent them the new images to try.

But I've moved on to Ravenna now. A much better system. I'm thinking about offering everything on my Mivera webshop as DIY kits since I've gone to 100% OEM work through my other company.