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PeterSt

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  1. Hey Barrows, I don't see you talking about how to get in that data over Ethernet; it needs to be "pulled". Async USB virtually uses the 24MHz clock for that. The buffer is USB itself. Regards, Peter
  2. Unfortunately it is not possible to stuff the thick gauge wires in a UCB C small connector. People asked before and we tried, but it just does not fit in there. And changing the cable wiring itself is not an option (IMHO). Regards, Peter
  3. Dear @elcorso, Dear Roch, Thank you very much from all the great inspiration from the rainforest. That you may be remembered by all those who shared your hobby and beyond. Your last cable has been sent. Hugs, Peter
  4. I obtained it, but never really used it in commercial products. Why ? It reflects EMI. And since this radiating stuff is a kind of wide beam anyway, you won't know where it is going instead, unless you can measure it (which we can). So put it on the lid like suggested and it goes where now ? ... yeah, well ... now it becomes harder to measure because where to put your measurement probe exactly while it has become one big flood of EMI anyway. My point is : you would want to put it in or on a radiating device in the first place but it will affect the radiating device itself. And while not so many devices exist in your chain, avoiding a preamp in the first place, what is left is the DAC. And that must be protected from itself. Btw hint : connections radiate the most. Not really chips (clocks) as you might expect. Not-terminated cables are the worst. E.g. a USB cable that is put in at one end. Now observe the EMI at the other end. You could shield that with a sheet of this. But you will only spread it (diffuse it) into space, while the solution is disconnect that cable. Decent grounding (/ termination) appears always the better solution. But it is quite hard to tell what and how if you can't measure it. Those sheets (of a few types for generally 3 types of radiation) are almost like snake oil; technically they work, but functionally it is too difficult to apply them. Also, be careful at applying them in electronics, because often they conduct (some times on one side only) and you thus just can't lay them over all the exposed wires and pins and such. But then again, that would be about preventing the radiation to go out, while the word is to prevent it from going in (think DAC again, which needs to be protected from itself). ... The picture from 3M would be correct ... (mind the both ways) Both feet back on the ground, net it is about what measures on the electrical output of the DAC or poweramp if you want. Hence that is what will be audible (theoretically). Well, be in for a couple of surprises when you, for example, thought to do right with your battery powered laptop playing the music. The subject is quite large.
  5. Hi Sven, Thank you very much for this detailed report. This is already great because - as told - nobody ever report about these cables and then there is nothing to work out or improve either (and I remain blind). Please be careful not to get fed up with all the configuration possibilities; it is too easy to start randomly change and get mad. Best would be to find a change in sound by a rough change (like disconnecting all on one side) and then envision what you actually hear. I mean, what the physics behind what you perceive for change could be. In order to be able to do this, look at the schematic of the configuration you implied (you have a few examples only, but they should be sufficient to work out the one you just dialed in). With this, try to see through that you are influencing this : - regarding this picture it is the timing jitter and the amplitude noise. The more thin those lines are, the less jitter will be in order, the better the sound should be (whatever "better" means, because it can be so that technically better implies that other anomalies in the system become audible - still it is best to have the least jitter). In your case you have the additional dimension of using a wordclock (cable). It is a bit hard for me to see through the dynamics of that because I think it now can be so that you are using two signals which are about equal (the difference would be the difference in cable induced jitter) and they will oscillate (never mind this will be at a minute level deep down somewhere in your DAC). Only if the clock wire of your HDMI is not connected, this would be avoided (if I understand correctly how all is connected in the first place). Oscillation of this kind is killing, as it will imply a very slow changing jitter spectrum and this would exhibit as not-stable sound. Please notice that I don't mean that the two clock signals are connected somewhere - it is about the noise both will imply (in-DAC) and that interferes / influences each other. When you are working with this, and you indeed are able to envision what happens inside (no matter whether you are correct on it), you will see that you have 50% chance of changing further in the correct direction. Thus, you change something, then you e.g. perceive more or better (less distorted) highs, and from there you envision how to improve this, based on your thoughts. Then you apply a next change in that direction of which you think it is correct and or it is correct indeed, or it works out the other way around. But, now you know where the direction is to be and can proceed from there (like making the shield LONGER because that is what you do when you'd sequentially connect the shields when nothing is connected in parallel). Dizzy ? For your Lush^2 or ^3 it works the same, but far more complicated; there too jitter is in order, but not at a direct signal level. This is because USB is based on a protocol (with packets and (varying) packet sizes and such) and you can't say that less jitter will sound better. But it will be different anyway. In your situation the fun would be that you change things on your HDMI connection while the clock signal is not even used in there, while you still perceive changes. This would be similar to my own situation of having an ET^3 as Ethernet cable between a PC that connects over RDC to the (headless) audio PC, where no audio at all flows over that cable (it is only for screen and keyboard control) and that still the sound changes by this cable and its configurations. This is how the "minute" changes (say unmeasurable) still influence via diverse invisible backdoors, in the end always hammering on your precious clock signal. Peter
  6. Hi there Sven, Somehow people don't report on the HDMI^2 (ET^2 / ET^3 the same). Maybe this is because the application for these cables (i2s) is too specific plus it is not a "protocol" application (USB is and there all works out very different and more predictable). It is actually just analogue (never mind it is about 1's and 0's). The only difference that can emerge here, is about jitter (i2s carries the clock signal). Notice that jitter is audibly foremost discovered by means of the bass. Whether also "hall" (room) I wonder, so this could be a means to determine what it really is about. Notice, however, that lower jitter expresses as more firm bass (more of one frequency when one frequency was intended), which comes to you as LESS lower bass (the more the bass is fumbled, the lower it comes across, and you can feel this on the woofers (more frequencies running through each other)). The "room" as you express it, feels the same to me (fumbling), but I would be on a dangerous path to claim so (especially because you like it better :-)). N.b.: From the Lush^ you may recognize how the energy spectrum can vary from wide and flat to deep and holistic. And this by varying the configuration. ... For the i2s application I would not approach it like that - it will work differently. When all the shields are connected, you actually will create a more fuzzy signal path. It could be better shielding, but the path would also be "longer" so to speak. Or even better : there will be several paths for the ground, never mind it is not ground - it influences the signal under it (the data and clock wires). So what I would do : disconnect all small connectors on both ends. Now the shields at least do not influence each other. The shielding may be less, but it depends what actually bothers (we both don't know). *If* it happens that now the sound becomes even more "warm", it would be my idea that now you created (implied) too much jitter. And, if I am right then less jitter is always "better" as such, which does not tell what you like better. I can blather much more, but it would be best if you can find a difference to begin with. If you do, you may tell what you perceive, and if you don't like what you hear now, connect all he wires on the sending (A) side, and have the B side all disconnected. These variations should bring the largest differences because electrically they "do" the most (for differences). I don't use external i2s myself, so I can't judge. All I can do (could do) is design the very best cable for its properties (like gauge and shield types + isolation means and its properties). Best regards, Peter
  7. You don't want my trousers to fall down, do you ?
  8. Hey Mani - The Intona taking out general noise is nothing I have ever seen. However, it takes out (or lessens) the 8KHz USB protocol noise. So look at 8KHz (and 16KHz and 24KHz etc.). Regards, Peter
  9. Why not video the room and then grab all the individual frames and present those as photos you took ? 60fps should do, but you can go way beyond these days.
  10. By clicking the cross you see here : (I hope this is not too vague, but this is near the bottom of the screen)
  11. With a bit of spare time, I would like to hand people some advice, so that disappointments like with @mallikh can be avoided. And I mean for him/you, not per se for myself. In between lines : I have never experienced that it went wrong at the installation/assembly of the sent chips and I actually always wonder how it can be that people "know" that it is the PCM1704 chips which are failing. However, without exception (that I recall) people send feedback like you see one quote below, probably because they have been anxious whether what's sent would finally work or not (many people first tried AliExpress or something, and will find chips so fake that they are probable even empty inside). Here just the last feedback in my email : (the list is rather long and the quote is from someone near the top, where he orders more like announced in the quote via an email near the bottom) Hi Peter, Just got around to soldering the chips and everything is good…..at a later date I may add more to the DAC board,I still need 5 more but the replacements will have to wait. Thanks for your prompt response and help much appreciated! Cheers, [....] Hi Peter, Can you give me a good price on 6 of the PCM 1704 with postage please?same if as last order Pcm1704 K Thanks, -------------------------- Now what should this tell (hopefully) ? that none of these chips are falsified or not working otherwise. And to be honest - I even had them checked by TI in the US myself. What can you do with this ? a. Being sure that nothing is wrong with them - you have my guarantee. Thus, you can feel secure (people who don't know me after 15 years may be less comfortable doing so); b. NOT being sure at all that your device in question is OK in all other places. So it is about this latter. And btw, where I could theoretically help with audio DAC solutions, it's getting a bit weirder once you (I) learn that these chips were used in ultra high precision weighing machines, telescopes and of course more where I did not think of. Now I do, because the chips are sent to all these instances. Now with Mallikh as the example - by email I also tried to help out, by pointing out that the chips are fine and the culprit thus has to be sought in the other parts of the device in question. That it always, so far, has been so that indeed the chips were burnt somehow (still unbelievable for me - see the beginning of this thread), is ... people's luck ? As I told, Maillikh does not have knowledge of electronics and why would he, as long as someone else has - him/her doing the work. What I wrote to him and what may count for others too, is this (literal copy and Maillkh can tell if it is not the truth). N.b.: This is the last email in full so no context is left out. The real message to you, potential buyer of the chips, is that nothing can go wrong as long as you first trust the good shape of the chips. So here goes : All right xxxx. It is your choice not to answer my questions thoroughly. But that will not help you really. > checked thoroughly all the circuit for 4 days I believe that. But in that case you can show me the bitclock and wordclock outputs from (???) to the IC's ? Please don't hesitate to be technical - I design D/A converters. We build them in-house as well. And maybe I told you : we used 1000s of these chips and none whatsoever failed ever. Also not the 100s or so we shipped later, like to you. So the chips are all right. Hint : I don't think you can check the circuit (of some device you dont want to tell ?). And if you can measure for real - just show me. - bitclock -wordclock -masterclock (oscillator). -when you're at it anyway, the data (this would show eye diagram). Now tell me the device FIRST before continuing. OK ? Kind regards, Peter The sheer fact that this did not happen (no response any more) tells me by guarantee that the engineer with knowledge maybe has no knowledge (or equipment) and that maybe he does not even exist. But those with the (DIY) knowledge know exactly what this is all about : the strict proof that the device itself is OK in advance of the chips, and if so, we'd need to look behind the chips or possibly upside-down soldering. And look, the email itself testifies from this path, which I would do for free and to help out. It will happen to anyone within reason. Unless you cut the path yourself of course, then nothing remains (like in this case). What I see happening lately, is that people obtain some ever back good device for 100 euros, don't get sound out of it to next "know" that it will be about the PCM1704's. And alas, somehow they are always right (except for this one case, as it seems). All in other words, please be careful before buying. Also - and I had this in mind for Mallikh - if your device does not work and you can't find the culprit, just sell them as 2nd hand for about the same price, locally (but be sure you did not burn them). You may even take profit over it. And try one channel first. No more lyrics. Peter
  12. I now see that it can comes across as wrong language ... I meant financially. Apologies.
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