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  2. #Yoda#

    MQA is Vaporware

    It seems as if publishing new albums in minimal HiRes requirements to a superior price, is the new strategy of many labels that are not focused on Jazz or Classical, to secure their crown jewels since they've noticed that the download numbers for MQA albums are continuously marginal. Meanwhile I'm quite happy for any well produced Americana or Indie Rock/-Folk album that is being published in at least 24/88.2 or /96.
  3. BrokeLinuxPhile

    Official Qobuz Issues Thread

    @Hugo9000 Thanks for the clarification on what MQS is. Unfortunately that just confuses me even more about Rumours actually is if you buy it from Qobuz right now. There should be better truth in labelling if you are going to buy something outright IMO.
  4. It works quite nicely both ways, with some amount of practice/training. Brain is pretty good in filtering out this. So you can mentally block the background noise of sea as well as "noise of symphony orchestra playing" and focus on something that is behind it. That's kind of the traditional thing of having a conversation in a noisy bar or night club, not unusual of having 90 dB(A) background noise and someone talking at 60 dB.
  5. Jud

    Album of the Evening

    Any thoughts about SQ from anyone who's heard it on Qobuz? Bop 'til You Drop sounds quite good, though you might want to turn it up. The levels are low next to current Loudness Wsrs product.
  6. If any of that EMI escapes the computer in first place. And then figure out if any of this makes any difference whatsoever to the DAC in question. One big source of EMI is the iPad everybody & friends seem to be fancy of using as "remote control" (not me though) with potentially both cellular and WiFi transmitters. Cellular modem banging out it's pulsed traffic at 2W transmit power is quite a source indeed when you are having a call or otherwise transferring data. For that to matter, the internal DAC design first needs to be less messy than the potentially incoming disturbance. Which is also not always the case. Scope not, but FFT nicely shows the UAC packet traffic at 8 kHz (125 µs packet interval). Not hard to spot at all. And not related to any more or less fancy clocking in the USB. Actually fancier the clocking, more pronounced and well defined this ticking becomes. Calls for spread spectrum clocking here. Ethernet is a ground isolator unless you spoil it with shielded cable connecting grounds... And for example with something like NAA you don't need a "reclocker", because it only has one clock. But it is clockless until the NAA.
  7. biosailor

    Album of the Evening

  8. I've often thought that the whole supposed falling out between Larry and Gavin was just another part of the ruse. Gavin wasn't truly shown the door in my opinion, he was hired to do a certain job, that is raise millions in IGG funding, and when that job was done he walked with his predetermined cut. The ruse bestowed on the backers was then furthered with a cover story that there was some deep falling out between the two, which fit the whole theme of disarray and gee we're sorry we've fallen behind, and wow Larry wasn't even aware of what marketing was doing, and so yeah we're going to now make Gavin the fall guy because lets face it, he isn't even here anymore to be questioned. So remove the guy that made all of the public promises, send him on his way with a nice fat (predetermined?) payout severance, and then use that story to further the delaying tactics. The only reason I'd want to doubt the above is this has for certain ruined Gavin's career in the industry, and so Larry would have had to pay him a relatively large sum to go quietly. Anyone able to search pending or settled litigation between Mr. Fish and Larry Ho or LH Labs/Light Harmonic?
  9. Yes, this is why we can "listen into the noise," as we know from your sonar and sonar training experience; and for those of us who are a little older 😉, looking for faraway AM stations to listen to on our transistor radios. The interesting thing for high end audio would be the reverse: To what extent can we sense the "pollution" of a pattern, such as a symphony orchestra playing, by a small amount of noise?
  10. Those cracks in the Qobuz catalog have been allowing albums better off hidden away to see the light of day. I nearly retched when it spit this one out.
  11. Please help me understand something - The Sonore rendus accept ethernet in and USB out, D to D converters. If you are using, say HQplayer or Roon, what's the benefit of the rendu if it requires a cleaned up signal (e.g.: not from a stock computer with a noisy switching PSU, D to D MB converters, etc)? If I spend the time and $ to clean up the signal at the source (the computer) then why do I need a rendu versus connecting an optimised PC direct to the DAC? Isn't that one of the main reasons for the rendus coupled with a LPSU and internal femto reclocking? I'm not trying to dismiss the qualities and benefits of the rendus, but want to ensure I understand the rendu's purpose for my configuration.
  12. Of course not, the relevance was only that data storage is not always 0/1, but sometimes something quite in between...
  13. One more question from me: Why is Larry selling the Source on his website when it's a crowdfunded product that's not fully delivered yet? And if I'm not mistaken he's planing to do the same with the Wave and sell in under the Light Harmonic brand. Suckers pay for R&D and profit.
  14. ddetaey

    router or switch?

    I think this absolutely fine. And since you have it, start using it. If you feel something missing, you can always upgrade later. Dirk
  15. Indeed. Banishing CMOS and its power spikes would be wonderful. But have you looked at the prices (and poor availability)for ECL flops and CMOS>ECL converter chips? Not to mention that I seem to recall them being current-hungry little beasts.
  16. KenG

    Official Qobuz Issues Thread

    So far I like the service and appreciate all the hard work you and your teams put into the Beta and 2/14 launch. I am still noticing quite a few holes major Independent artist like Elliott Smith, Spoon, Husker Du and Radiohead but presume these are coming. I noticed that a lot of the major Matador Records and XL catalog was added over the past few days.
  17. semente

    Album of the Evening

    P.S.> available from Qobuz for £3 - https://www.qobuz.com/gb-en/album/kocsis-plays-bartok-zoltan-kocsis/zjqkxji75pihb
  18. semente

    Album of the Evening

    This PCM recording was first issued as an LP: Recorded 23rd & 24th October 1975 at the Arakawa Kumin Kaikan Studio, Tokyo Denon PCM Recording https://www.discogs.com/Zoltán-Kocsis-Plays-Béla-Bartók-Allegro-Barbaro-Three-Rondos-On-Folk-Tunes-Suite-Sonata/release/7954587
  19. koupa

    Article: Yamaha NX-N500 Network Powered Speaker Review

    Unfortunately the traditional USB is a very bad protocol. But it stormed the Industry 25 years ago because the former protocols were even worse and it unified some things. Firewire for example was much much better but except Sony and Apple no one in the consumer market used it. The Pros were something else end I don't count them. I hope now with the USB-C / Thunderbolt protocol some things to be improved. Things should be simple. Work or not.
  20. A memory device could easily allow common mode noise to flow around it, and the effects on phase noise/jitter could vastly outweigh anything else (eg crosstalk) again I’m not discussing digital rather analog — I understand bits quite well thanks.
  21. Today
  22. Does your DAC use a hard drive for intermediate storage between the USB receiver and the conversion circuit? If not, I fail to see how that has any relevance whatsoever.
  23. Seems a good place to repost John’s explaination and hypothesis. And no, his test system is not done yet. The first multi-board setup had poor signal integrity due to a bunch of semi-expensive coax cables connecting them, so he redesigned the board (also using some newer, high-speed, ultra-low jitter parts that recently became avaialble). His work on this measurement project is mostly limited to time in-between product development work. @JohnSwenson, October 2017 The hypothesis goes thusly: ALL crystal oscillators exhibit frequency change with power supply voltage change. This is known and well measured. A cyclical change in voltage causes a cyclical change in frequency which shows up in phase noise plots. For example if you apply a 100Hz signal to the power supply of the oscillator you will see a 100Hz spur in the phase noise plot. A circuit that has a digital stream running through it will will generate noise on the power and ground planes of the PCB just from the transistors turning on and off that are processing that stream. This effect is very well known and measured. Combine this with the previous paragraph and you have jitter on the incoming data stream producing varying noise on the PG planes that modulates the clock increasing its jitter.  The above has been measured.  But shouldn't ground plane isolation and reclockers fix this? At first glance you would think so, but look carefully at what is happening. What is a reclocker? A flip flop. The incoming data with a particular phase noise profile goes through transistors inside the flip flop. Those transistors switching create noise on its internal PG traces, wires in the package and traces on the board. This noise is directly related to the phase noise profile of the incoming data. This PG noise changes the thresholds of the transistors that are clocking the data out thus overlaying the phase noise profile of the local clock with that of the clock used to generate the stream that is being reclocked. This process is hard to see, so I am working on a test setup that generates a "marker" in the phase noise of the incoming clock so it becomes easy to see this phase noise overlaying process. This process has always been there but has been masked by the phase noise of the local clock itself. Now that we are using much lower phase noise local clocks this overlying is a significantly larger percentage of the total phase noise from the local clock.  Digital isolators used in ground plane isolation schemes don't help this. Jitter on the input to the isolator still shows up on the output, with added jitter from the isolators. This combination of original phase noise and that added by the isolator is what goes into the reclocking flip flop, increasing the jitter in the local clock. Some great strides have been made in the digital isolator space, significantly decreasing the added phase noise which over all helps, but now the phase noise from the input is a larger percentage, so changes to it are more obvious.  The result is that even digital isolators and reclocking don't completely block the phase noise contribution of the incoming data stream. It can help, but it doesn't get rid of it.  For USB (and Ethernet) it gets more complicated since the data is not a continuous stream, it comes in packets, thus this PG noise comes in bursts. This makes analysis of this in real systems much more difficult since most of the time it is not there. Thus any affects to an audio stream come and go. Thus just looking at a scope is not going to show anything since any distortion caused by this only happens when the data over the bus actually comes in. To look at anything with a scope will take synchronizing to the packet arrivals. Things like FFTs get problematic as well since what you are trying to measure is not constant . It will probably take something like wavelet analysis to see what is really happening.  The next step in my ongoing saga is to actually measure these effects on a DAC output. Again I have to build my own test equipment. The primary tool is going to be an ADC with a clock with lower phase noise than the changes which occur from the above. AND it needs to be 24 bits or so resolution. You just can't go out and buy these, they don't exist. So I build it myself. I have done the design and have the boards and parts, but haven't had time to get them assembled yet. Then there is a ton of software to make this all work. Fortunately a large part already exists, designed to work with other systems but I can re-purpose it for this. So it's not going to be right away, but hopefully not too off in the future I should be able to get to actually testing the end to end path of clock interactions all the way to DAC output. John S. ===========
  24. This is a really interesting topic SSC is used explicitly to reduce EMI in motherboards that otherwise aren’t able to pass FCC certs. So look at why the EMI is so high and there are lots of reasons ... including pushing digital logic circuits beyond what they were originally intended to do eg CMOS. Perhaps if ECL had originally won out this wouldn’t be an issue. Rather than SSC the DAC, I’d favor isolating the common mode EMI transmitter aka overclocked Xeon motherboard 😂 ... fiberoptic Ethernet is a very effective isolation method ... and then engineer the DAC/Amp properly for low EMI 🤷🏻‍♂️
  25. I was responding to this: Why did you say that if you don't want to talk about clocking and buffers? You appear to be suggesting that a memory device can somehow pass on jitter from the writer to the reader. That's pretty much the central tenet of Alex's beliefs. We were. Then you completely changed the subject. Your outburst was somewhat incoherent, though, so perhaps I misunderstood what you were trying to say (besides insulting me). Are you drunk or something? You usually make a lot more sense than you have done in the last few posts.
  26. Rt66indierock

    MQA is Vaporware

    Thanks I notice a lot of the Americana is 24/44.1. A pretty normal ADC output for quite awhile.
  27. The Computer Audiophile

    Article: Yamaha NX-N500 Network Powered Speaker Review

    Great to hear the cable fixed it.
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