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PeterSt

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  1. I'm afraid they don't understand their (so-called) jobs. Btw, this is warranted. I am not shouting loudly or anything.
  2. Anyone familiar with them ... coffee shops have been closed down over here. As I understand it, now music will sound a little worse.
  3. That depends on how much the galvanic isolation helps in the first place. Haha. (this already implies that the total of 100 is not that, but may vary between 0 and 100) So now let's say it possibly helps 100 in total. But in your system the isolation helps 20. Now the isolation itself implies added jitter (this just is so; please take my word for it). Now you need the re-generation to diminish that added jitter again. Do we reach 100 now ? No, because that depends again; Say that the jitter figure was -60 without the isolator. Also let's say that jitter is always detrimental (a dangerous assumption to begin with). With isolator the jitter becomes -80. With re-generation the jitter becomes -20. So what did we gain net ? I see a 20 and a -20 ... Now a kind of problem : ... So without isolation the jitter is -60. With re-generation the jitter is ... -20 again. Please take this as a fact (the re-generation implies an absolute jitter figure and the extra jitter because of the isolator is unimportant). My "math" coincidentally ends up at 0 difference, net. But it can easily be +30 or occasionally -10. There's one other matter to be factored in: Any "generation" is audible. This will be because it implies jitter itself and it will be highly deterministic (oscillating patterns). This is audible in the Intona once you are used to it longer term (you start to recognize the flavor). I here it too in any other re-generating device (mind you, as a specific flavor). So in my personal view any re-generating device adds something which wasn't there in the first place (no re-generation adds nothing). If the jitter was at -60 and it ends up to be at -20, it can well be that the -20 -although with a better jitter (RMS) figure- is more audible than the -60 figure, because of the pattern-like flavor in the -20 situation. Also, sadly the -20 situation is a lower jitter number, so any deviation (the pattern) is better audible at that level than when it is buried in the "more noise" of the -60 level. And so it all depends ... And let me end with the again "fact" that jitter in this digital domain (because that is where the isolation operates) should not even be audible. Or better put: "do" anything. But it surely does via very sneaky ways, quite beyond the topic of this thread. However, it is the same topic as the sheer reason why USB isolation should help in the first place. In the end it is all about how the DAC can be influenced by means of jitter hammering on the power supplies or inherent noise itself being detrimental for a best clock signal. Was this something for an answer ? of course not. But that difficult - or complex it is ... Peter
  4. Yes, I think the Intona can bear this situation. N.b.: I introduced the Intona to this world of audio usage. The Alldaq description / prescription could be correct, but almost certainly not in all situations. Generally the idea is that a. you leave all on 24/7 when it likes to work for you finally (haha) or b. that you know what to repeatedly do each time (like which end of which USB cable to un- and replug). There are no general rules that I found, over the period of time that I worked (designed with) this stuff myself; it can be hit and miss quite easily. Why not try an ISO REGEN from Alex @Superdad ? At least they have the experience with 1000s. Do notice that the AllDaq is USB3 which the Intona IMO is not (unless by now it is) and that the ISO REGEN also is not (USB2). But I don't think you need that ? Good luck ? Peter
  5. For those who like mud throwing ... I have sad news. BOTH parties here are to be trusted, but both apparently do not have the experience ... well ... I have. This is how it should look like when customs opened a package for inspection (see the green tape). But this surely does not happen all the time; I experienced this only once that I have heard of, plus coincidentally once with a flight of my own. But packages are opened all the time ... And when not sealed with explicit tape, it's often carefully sealed again, the customer not even knowing how we packed it. On a side note, the picture above does not show the real damages to these both boxes, but I guarantee you they look as 10-times used. But both boxes were new when they left here. What am I getting at ? In one of the boxes you see, there is a PC from us. The thing was taken apart completely. Cooling fan cables were not connected any more, switches had been taken out and put back in upside down (very cosy (not) for a dipswitch and trouble-shooting further problems), and then also to notice that the whole issue came to light when the PC ran hot and we couldn't tell how. The prosperous matter in this case is that this concerned a long-term customer who started blaming customs right from the start instead of thinking that our QC wasn't the best. Of course the tape customs applied helps too here. Talking about Lush^2 ... only 3 months or so back, a customer received an open package (he saw it being dropped on his doorstep while it was open), the both crucial connectors missing from the package. Had this package been sealed again (nicely or poorly) he would have been assured we forgot the connectors. I have so many stories, some working out OK, some working out not-so-good (costing someone additional money). But one thing: I take it for granted right from the start that customs does these things. And I quite well know in which countries this happens (Malaysia included, Thailand included (photo above). Point is: you just can't imagine what they all do to find strange stuff inside, or why in haven's sake switches get disassembled. Or why cooling fans power connectors are taken off. And not one, but even two. In the end most probably everything, but then they don't know where to put it back. It is outrageous. And from the customer: Attached please find photos of cooling fan and wire harness tied near the front panel. I found one Y-connector cord which is unconnected. Is the fan (mounted on right side panel) male connector supposed to be connected with this famale Y cable ? Also I noticed that the emergency cooling switch (right front) does not kick start the two emergency fans automatically when the switch is up (auto mode) even the CPU temp is 60 C ? What is the CPU temp to auto kick start the fans ? When playing back I always turn on emergency fans by lower the emergency switch. What is the normal setting for emergency switch ? Yes, this too took numerous emails to a. sort out what was going on and b. solve the issues (after finding them). But all in good spirit and then suddenly money doesn't play a role much. In the case of Y A I myself am pretty sure that customs didn't have a torque screwdriver at hand and so they tried something else instead. The picture shown (later in the thread) obviously shows total-damage to the screws which never ever will be from a little worn-out screw driver. But what obviously goes wrong here is that person A blames person B because customs can't have done this, and person B feels attacked and does not investigate further whether maybe the shown pictures could lead to customs behavior after all. And then they start fighting instead of blaming customs ... Really, the number of times such things happened to us are not countable on two hands, so one can suspect such issues if even the slightest looks or feels wrong. Add to this the nature of people from that area (which includes not being able to buy proper tools, which includes feeling helpless because no "physical help" available really, which includes, well, all we would not be able to envision because we live in "the west". Maybe @STC can confirm this by his angle of view (no need to respond if you don't like to). No worries. Y A is a fine customer already (which out of all happened after this thread emerged, while I only found it today). And let me add to it that some people are more demanding than others which again originates from the "being helpless" which really is so for quite some countries in this world. The verdict: Alex @Superdad, you apparently missed the fact that customs do this to you. If still possible, someone should open that unit and find the source of the rattling noise. You may well find my PC situation in there. Y A @mikey8811, you couldn't know and had no other choice than blaming the supplier. For a next time, investigate the techniques people or companies (or customs) use to let packaging look like unopened. Also maybe investigate track records of people / suppliers (/ manufacturers) to see the ill-logic of matters. Alex, what could be lose inside ? Answer: nothing I bet ya. Unless something happens (happened) to it like that PC. Addendum for a bit of fun: I once sent a non-insured low jitter clock assembly to a local customer in Holland, by normal mail. It got lost. I sent a next assembly to the same customer, knowing that the chances would be too low to let that happen again. So why to insure it (value was 120 euros or so). It got lost again. Then I agreed with the customer to over-value and insure it for 500 euros; we agreed money would be left for a nice dinner for two if it would happen again and I could claim the 500. And yes, it happened and the claim of 500 was in order and fulfilled. OK, the dinner never happened. The customer now came collecting his clock assembly. Sh*t happens everywhere, and sometimes of magnitudes we can not imagine. I hope you two can get along again and that Y A is eventually able to make a nice Thai ending (ahum) of all his forum threads; I really can't imagine the slightest that Alex / Uptone is even capable of doing the things he is accused of, but this, sadly, includes the kind of admitting that it could have happened in his offices, looking at the screws (Alex, man, look closer !). And Y A, please, I tell you that Alex can be trusted (I am a customer too, he is a customer too, etc.). And if you can't trust him then you better don't trust me as well (FWIW - haha). I feel quite similar(ly operating). Regards, Peter
  6. A great interview. Thanks ! And the only person I can think of to refuse to write about our DAC because he instantly heard how the speaker we used at some US audio show, distorted in the tweeter. Imagine : ahead of the show we tweaked and tweaked and tweaked to make that speaker sounding right ( I should be able to find photos of what we all did to that for the given (to us) speaker for this show). We were quite nervous at explaining to every one requiring it, that something was wrong with the speaker and it surely wasn't our DAC (such a weak excuse !). But John, out of all, worked the other way around: he was comfortably assuring me that no review etc. was possible with these speakers. And I wondered how the heck he came to that conclusion seconds after he walked into our room. If I only would allow myself to put up the photos at the end of the show, we all literally rolling on the floor of laughing because of having so much after-show fun. Out of respect I always kept them hidden on my hard drive.
  7. Yea, cool. Do you have a use case for this ? Apologies for being serious. Speaking of that, is this the spray you used ?
  8. I wish I made photographs of all the (very low voltage) fan means I applied to the cooling part. So the Peltier element would cool itself. It always worked ... ... temporarily. Next up : perpetuum mobile
  9. You bet. But I'll start with sound quality. I am really used by the other way around by now. So yesterday I deliberately did not start this software process (of the next 24 hour implying playback). Sound is really more "relaxed" because of this. This, while I know for 5-6 years by now that in my specific situation, playback needs to commence for ~20 minutes to develop a balanced sounding operation. With the 24/7 thing this indeed lacks (no difference audible for whatever next minutes of inital playback). But doing nothing (the past 24/7) is also not good (again, in the situation I have at hand here). So it is all quite sensitive. The Peltier solution can be tuned to the most sensitive temperature setting with resistors (I did not try, but is should work).
  10. Btw, don't underestimate other sources of influence because of heat. Of course it depends completely on the design. But for example, the DC Offset measured at a DAC output is always subject to heat somewhere along the chain (within the D/A process, including the gain stage). DC Offset also applies to a differential setup, where it manifests in THD aggressively (plus and minus are influenced differently). So this is now now expressed in THD per D/A element (like a mono channel chip) but to the net result (plus and minus fighting).
  11. Try it. With really low TDP (like measuring 25C or so at the chip's surface) continuous operation on any of the chips, no continuous use would show a higher temperature. Still, running that for 24/7 will degrade THD by the ever so slightest means (like 0.002dB or so). This is audible like crazy (perhaps because of means beyond my knowledge). You applied it the other way around: cool the chips to a relevant degree, and measure a sheer 5dB of less THD. I believe you without checking. Btw, 5dB is rather much, but easy to accomplish by this aggressive means (like a heat source would do it the other way around I guess). So yes, it is the way to go. I am quite confident of that.
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