[GoldenSound]

I also guess @Rob Watts DAC's arent fool proof and ofc his buffer can be over/underrun when going extreme. But i think hes built in enough margin to hardly become a problem in most usecases. I do read his DPLL deployed a unique correction meganism.

Perhaps he can chime in on that one.

Chord uses a PLL so buffer overrun/underrun wouldn't be an issue

 

[ecwl]

Really bad SPDIF source:


This is way better than most DACs, and especially excellent considering this is a small portable device!
Many wouldn't even lock to the source used on the last one and the second one they'd show much higher jitter.
But the word 'immune' isn't really applicable.

Haha. You set a very high bar for immune. But point well taken. Thanks for showing the measurements.

 

[GuiltyRocker]

Just as a demo on the Mojo 2

Very low jitter SPDIF source:


Moderate jitter SPDIF source:


Really bad SPDIF source:


This is way better than most DACs, and especially excellent considering this is a small portable device!
Many wouldn't even lock to the source used on the last one and the second one they'd show much higher jitter.
But the word 'immune' isn't really applicable.

Since this is below the threshold of audibility, it basically is immune, try that one of those Chi-Fi crap DACs, I want to see that.

 

[GoldenSound]

Since this is below the threshold of audibility, it basically is immune, try that one of those Chi-Fi crap DACs, I want to see that.

Sure but you can then say the same for 99% of dacs on the market

 

[GuiltyRocker]

Sure but you can then say the same for 99% of dacs on the market

Sure, but not as good as this.

 

[GoldenSound]

Sure, but not as good as this.

I mean the best one I've tested in terms of PLL Jitter rejection is the May, which is Chinese.

Im not sure why you have a strong aversion to stuff from China?

 

[GuiltyRocker]

I mean the best one I've tested in terms of PLL Jitter rejection is the May, which is Chinese.

Im not sure why you have a strong aversion to stuff from China?

Because so far all I've heard from there is terrible including that Holo May, I listened to that DAC and it was downright mediocre. It was so boring and bland it put me to sleep, it could work as insomnia medication if I ever need it that's for sure.

 

[alxw0w]

Just as a demo on the Mojo 2

Very low jitter SPDIF source:


Moderate jitter SPDIF source:


Really bad SPDIF source:


This is way better than most DACs, and especially excellent considering this is a small portable device!
Many wouldn't even lock to the source used on the last one and the second one they'd show much higher jitter.
But the word 'immune' isn't really applicable.

So as we see with any decent source jitter is not a concern.

As it is with any decent dac for quite some time.

 

[OneOfTheLastMen]

Just as a demo on the Mojo 2

Very low jitter SPDIF source:


Moderate jitter SPDIF source:


Really bad SPDIF source:


This is way better than most DACs, and especially excellent considering this is a small portable device!
Many wouldn't even lock to the source used on the last one and the second one they'd show much higher jitter.
But the word 'immune' isn't really applicable.

Thanks for the excellent information and explanation. The next obvious question is how will we know if we have a "good" SPDIF source? Is it reasonable to assume a well reviewed CD player / transport or streamer will provide reasonably low jitter data? My sources are Cambridge Audio CXC CD transport and WiiM Pro streamer. I am assuming those are good, but haven't seen any reviews of either that provide measurements of jitter output.

 

[OneOfTheLastMen]

I have read up extensively on the way CD transports do error correction. Basically using a fairly complex buffer algorithm that can reconstruct data even where some data is unreadable or where it has to re-read a sector more than once, and then reclocking it at the output. CDs even include redundancy:

"CDs have checksums – each 2352-byte sector stores 288 bytes of ECC data for every 2048 bytes of user data, allowing some read errors to be detected and sometimes fixed automatically."

So hopefully a good CD transport will reclock data well with minimal jitter. But the customer is unlikely to know that unless a review includes measurements.

 

[GuiltyRocker]

I have read up extensively on the way CD transports do error correction. Basically using a fairly complex buffer algorithm that can reconstruct data even where some data is unreadable or where it has to re-read a sector more than once, and then reclocking it at the output. CDs even include redundancy:

"CDs have checksums – each 2352-byte sector stores 288 bytes of ECC data for every 2048 bytes of user data, allowing some read errors to be detected and sometimes fixed automatically."

So hopefully a good CD transport will reclock data well with minimal jitter. But the customer is unlikely to know that unless a review includes measurements.

I read that too, it's fascinating how it all works.

 

[Jawed]

Just as a demo on the Mojo 2

Really bad SPDIF source:


This is way better than most DACs, and especially excellent considering this is a small portable device!
Many wouldn't even lock to the source used on the last one and the second one they'd show much higher jitter.
But the word 'immune' isn't really applicable.

Is this a result published in an article? Just curious whether the connection scheme was described somewhere. USB? Optical? Was Mojo 2 running on battery power?

Also wondering whether you used different devices to produce the three different graphs. Curious how reproducible your test is, e.g. for Rob. Maybe you've already discussed it with him?

 

[esmit]

The SRC-DX is made to be able to feed a 705.6/768k signal into a Chord DAC with a dual BNC data input and to take processing load off the USB chip of the DAC. (so it will generate less internal noise)

It has few use as an input device for Mscaler as the scaler becomes redundant if you feed it 705.6/768k.

Better is to use toslink into the scaler to isolate electrically from your streamer.

You can still use the src-dx to feed your mscaler native 44/48/96 etc signal (you do not nessecarily need two cables then) without upsampling, just to replace USB. I do as I have TV and chromecast toslink (for Spotify). Isolation comes from reactcores optical solution between mscaler and tt2, but that is another story.

 

[JazzAudioDog]

I started by using the USB input of the MScaler from the PC. Than I bought a Nod2i and connected to the MScaler using Coax (with an adaptor RCA-BNC). The digital connection was much more natural sounding to me. Then I bought an Innuos server and returned to the USB connection into the MScaler; found it better the the PC but it still had a little glare, "artificial" kind of sound so then I tried the SrcDX with Wave Ref. cables and that changed everything for the good. I then tried the Singer SU-6 (with the included power supply or with the SBooster LPS) in place of the SrcDx and I preferred the SrcDx and that is what I use currently. I tried both the BNC and the optical output from the SU-6 and found zero difference between them. But the Src-Dx sounded better to me. My DAC is the Chord TT2 (connected by dual BNC Wave Ref cables to the MScaler). I preferred to invest in the Wave BNC cables to avoid the dual box plus 2 power supplies plus all the cable mess for the OptoDx.

Thank you for the details. I’m deciding between a Douk U2 XU208 USB to toslink optical converter using a new Lifatec glass cable or the SRC-DX with an AQ Carbon digital coax cable I have on-hand.

Or I may do nothing because it sounds so good right now. About 100 listening hours ago I upgraded several digital cables to Shunyata Alpha XC. Aurender streamer USB to MScaler and satellite router Ethernet to the streamer. I had previously upgraded the cable modem to main router Ethernet cable. It’s been a real ear opener! I‘ve gone through several different cables in these positions. Nothing has come close to these improvements and it made me want more.

 

[homeros8000]

Because so far all I've heard from there is terrible including that Holo May, I listened to that DAC and it was downright mediocre. It was so boring and bland it put me to sleep, it could work as insomnia medication if I ever need it that's for sure.

I have both Dave and May connected to the same source and amp/headphone. May is an excellent DAC for the price, and I prefer it over Dave.