That is one of the reasons I looked at the Zen streamer, all the available measurements indicate a very good and stable USB output.
Not sure if that does make a difference in the end though, but you got to chose something.
Jan
Not sure if that does make a difference in the end though, but you got to chose something.
Jan
Can you share some pointers to these measurements? I'd like to understand in what ways a given USB implementation can be better than others.
This is not USB, but did give me a good feeling for a competent implementation.
ifi Zen Stream Measurements and intro to streamers - GoldenSound
Jan
ifi Zen Stream Measurements and intro to streamers - GoldenSound
Jan
I see. The review says "...has poor to awful jitter and scheduling on SPDIF and USB.", which is silly when it comes to USB. As explained before, the clock of the audio data is not controlled by USB, but by the clock/oscillator inside your ADI DAC. This part of the review is just another example of HiFi fairydust gibberish.
Really? What I read is:
This is seriously fantastic noise levels, absolutely nothing here that anyone could possibly consider anything but fantastic. Well done ifi!
Even if for some reason your dac was so horribly designed that it just put all of this noise directly through to the output, it’d be at -107dB relative to 4v (in the 20hz-20khz band).
Absolutely fantastic performance here, Audible-band jitter is exceptional and HF jitter is still very low too.
Not quite as good as 48khz, but still very good. The ~2.5khz, 5khz and 10khz spikes are a little odd, but still very low and again, great performance.
Are we reading different things?
Jan
This is seriously fantastic noise levels, absolutely nothing here that anyone could possibly consider anything but fantastic. Well done ifi!
Even if for some reason your dac was so horribly designed that it just put all of this noise directly through to the output, it’d be at -107dB relative to 4v (in the 20hz-20khz band).
Absolutely fantastic performance here, Audible-band jitter is exceptional and HF jitter is still very low too.
Not quite as good as 48khz, but still very good. The ~2.5khz, 5khz and 10khz spikes are a little odd, but still very low and again, great performance.
Are we reading different things?
Jan
"SPDIF" in the figures. Also, measuring jitter from the USB is not possible, simply because THERE IS NO CLOCK ON THE USB!
Please re-read the explanations above: The ADI DAC pulls in the music data from the USB/streamer, but it uses its own internal clock, as the USB system does not provide a clock!
Please re-read the explanations above: The ADI DAC pulls in the music data from the USB/streamer, but it uses its own internal clock, as the USB system does not provide a clock!
Hey, I don't want to split hairs, and I understand that the USB doesn't have jitter because there isn't a clock to jitter.
But the graphs that you refer to that show the S/PDIF jitter have a caption saying that the data is fantastic!
So is that tester misleading us?
Jan
But the graphs that you refer to that show the S/PDIF jitter have a caption saying that the data is fantastic!
So is that tester misleading us?
Jan
It goes to show anything is worse than RPi in the eyes of the RPi disciples. Even though jitter of RPi is .. eh... ahem. The PSU and local decoupling on the PCB are not like many would like to see it too. It is religious you know so all that does not matter all of a sudden.
Don't let it get you down. The iFi device seems well designed with great care to reduce jitter and noise. It has a good PSU, has good onboard regulation with quite a few LDO regs and it has good quality passive parts. It certainly looks better than RPi. It is ridiculous that you have to defend a well measuring device which was your choice.
It would be nice to compare to an RPi. Via USB. Then report what device sounds best. I did that and then silence followed.
Don't let it get you down. The iFi device seems well designed with great care to reduce jitter and noise. It has a good PSU, has good onboard regulation with quite a few LDO regs and it has good quality passive parts. It certainly looks better than RPi. It is ridiculous that you have to defend a well measuring device which was your choice.
It would be nice to compare to an RPi. Via USB. Then report what device sounds best. I did that and then silence followed.
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The way I read the review is that he is saying the SPDIF output has a very clean clock when he wrote that there is "good data". I don't think its misleading, as long as you are aware that his discussion is abut the SPDIF data output and not something else.
Jean Paul: We all know that you are not a RPi fan. Please accept that I am not arguing about RPi or religion, but about the fact that "jitter" does not make much sense with USB audio data. Please stop trolling.
No! I like RPi but it simply is not the only device around that is OK and it certainly is not the best. It looks plain awful and cable management and HAT structure don't make that any better.
The man has bought an excellent iFi Zen stream and who is trolling here with continuous gelaber about RPi? When your neighbor bought a brand new Opel Insignia and starts to get to know it you start telling a BMW I3 really is better for hours too?
The man has bought an excellent iFi Zen stream and who is trolling here with continuous gelaber about RPi? When your neighbor bought a brand new Opel Insignia and starts to get to know it you start telling a BMW I3 really is better for hours too?
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You are simplifying this. The review was not made against ADI. There are still USB audio implementations that use synchronous mode. In this case the clock on the host side is very important.
Actually even asynchronous or adaptive implementations can be bodged and have jitter or over/underruns.
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I'm not defending, I just want to understand. I want to become just as smart as you guys! 😎
Jan
There is not much to understand with regards to performance as one can not do much as it are both ready made devices. Only the RPi can be pimped with HAT cards. Install that RPi 3B and use it via USB and compare to the iFi. Then you will know which device performs best and if USB makes sources irrelevant as stated here.
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True. The jitter of such a data stream would be awful indeed, and today's qualitt audio devices therefore do not wuse this method anymore. My point was that:
1. The review data show the SPDIF jitter.
2. The USB data going into Jan's ADI DAC will be clocked by the ADI internal clock, so the clock quality of the streamer is not relevant.
Well let's hope Jan will do that comparison of a plain 3B to the Zen stream. No HATs, just USB. I know what the answer will be.
Are you sure that Jan does not want to use this streamer with something else than the ADI?
there must be more...
So, when using asynchronous USB source, IYO it does not matter if the source is a RPI or whatever?
Checking some SOtM USB streamers, IYO it would not matter to use a "high end" sMS-200 ultra neo (best clock) or (cheaper) sMS-200 because their (cheapest) sMS100 would do the job equally well?
Allo USBridge with separate "dirty" and "clean" power supply is nonsense?
I don'thave the experience (yet), but I do believe in the more expensive streamers to sound better because of better power supplies, better PCB layouts and likely more.
So, when using asynchronous USB source, IYO it does not matter if the source is a RPI or whatever?
Checking some SOtM USB streamers, IYO it would not matter to use a "high end" sMS-200 ultra neo (best clock) or (cheaper) sMS-200 because their (cheapest) sMS100 would do the job equally well?
Allo USBridge with separate "dirty" and "clean" power supply is nonsense?
I don'thave the experience (yet), but I do believe in the more expensive streamers to sound better because of better power supplies, better PCB layouts and likely more.