lunatic

Thanks Matt. Stopping (instead of pausing) does produce the desired result. Is traffic flowing during paused playback? Is there some sort of keepalive exchange?

I have the same problem with Classe CP-800. Jriver MC19 running on win7. if I put the DAC on standby, music stops playing on jriver. Turning DAC back on, jriver is unresponsive and sometimes crashes. I just tried pressing stop, DAC on standby and back. This works, but I will have to see if I can do this with a time gap of hours between standby and ON. When I switch the DAC to standby, win7 makes the sound when it detects a USB device unplugged. Should I not be setting jriver output device explicitly to the DAC? Auto, perhaps. thanks

Just wanted to note that the Invicta FAQ addresses the issue of difference between USB and SD card inputs. I came across it by accident since the FAQ is under "Home" on their website and I didn't think to look under it. Here is what they have on their FAQ: Updated Notes: Prior to release 3 of our firmware, we got reports from beta-testers that the SD Card source ‘sounded better’ than USB, and we sought a reason for this in our design. It is hard to see why that would be, but experience teaches us to listen to our beta-testers and trust the feedback they give us, even if our design sense tells us that there should be no difference at all. We note that since Release 3 this difference between USB and SD Card is no longer reported. But truth to tell, we did not actually even know how to address the problem since we could only identify second order effects (as described below) which are all already removed to the maximum extent we know how to implement. USB buffering which was a possible candidate for the source of imperfection, is not in our control since we are the client, not the host, on the USB bus. However, Release 3 of the firmware is reported to have made SD Card and USB indistinguishable, and you may be interested to know what we did in Release 3 that seems to have serendipitously achieved this. Release 3.0.0 and later firstly removed the ‘polling’ of the user interface and replaced it with interrupt-driven user input. This means that after the DSP has set up the USB processing paths and so forth, it no longer need keep checking for user interaction: it only responds when an actual user-interface event occurs. Perhaps having more bearing on the issue, is that the software team found a redundant timing check in the USB data path and removed it. This timing check was ensuring a precise lock to the internal low phase noise clock, but it turns out that the data was already in that clock domain, hence this step was not necessary and removed. Finally, FLAC decoding capability was added to the system. To achieve the real-time decompression ‘on-the-fly’ at 192kS/s was a significant challenge. Thankfully, we were able to do this in all INVICTAs that we have ever shipped, due to an op-code level optimization of the processor. That is, not relying on the compiler to give optimum operation code sequences, but actually examining them and hand-optimizing where a clear improvement was possible. We even went so far as to add additional hardware units to the processor to improve its op-code utilization. (This is possible since the processors in INVTCA and CONCERO are the MicroBlaze reconfigurable processors from Xilinx). All this has led to a very efficient processor architecture that needs fewer clock cycles to complete common audio tasks. These changes are now reported to make USB and SDCard exactly the same high quality audio. But, as you can see, it is unclear exactly where the fault was (if indeed there was one at all) and why Release 3 by all accounts has improved it.

Thanks for the replies. Fair points but there is a lot of uncertainty around what it is that the human ear can hear that we can't measure yet. So am I supposed to rely on faith? Maybe measurements don't prove the non-existence of a difference between A & B but at the very least, measurements can prove that there is indeed a difference between A & B if any. Most of the "audiophile" industry is selling snake oil to people suffering from cognitive dissonance. I myself am not immune to that but at least I am aware of it and take measures to counter it. I don't trust my ears to tell the difference between the same note played twice within a few seconds. I certainly do not trust someone else's ears as now we are also including subjective opinions into the list. Science has not come this far because the Einsteins and Newtons gave their subjective opinions on things. Things were proved and verified by the scientific community. Apparently this sort of scrutiny does not apply to all things audio because somehow this field is "special". The human ear has super powers that are beyond the realms of science as we know it. Even in 2013. @mav52 I don't care much for reviews. Reviews help raise my awareness on what's out there. I generally try to read as much as I can about how a product is designed and then try it for myself if there is the possibility. Companies that don't reveal much about how they designed their product generally repel me. Sorry to take this thread off-topic. I will stop it now. The Invicta does look very interesting and it looks like a well thought out product. Pricing is a little steep given the competition. I'd definitely like to compare it to the Lynx Hilo.

A null test usually involves letting the device in question convert to analog and then something else converts it back to digital. What you are suggesting is that there is a difference the human ear can pick up that the measured output cannot. This implies that the D-A converter is producing analog signals that only the human ear can pick up but not the A-D converter. This in turn implies that the D-A converters are superior to the A-D converters. That is a rather strange assertion to make. A/B comparisons are non scientific. There is a published paper on the memory of human hearing that I don't remember too well but the memory is supposed to be less than a second. That is a pretty volatile entity to rely on. The digital domain is well established. We are not questioning the laws of gravity are we? If we start questioning the instruments we use for measurement, then we should stop using thermometers and stethoscopes. Lets just touch and feel shall we? IMO, if you are a "professional" reviewer and for any difference measurement you are not using null tests, then you are a waste of my time. If you are trying different USB cables, you are wasting my time. On a side note: If one is using only USB and wants to use an outboard preamp, then is there any difference between the output of the Invicta and Concero? This is a > $3000 question, so someone please answer it

So far, I've read only the 6moons review and I stopped reading where they said there is a difference in sound between inputs. This sort of thing gets on my nerves. Same issue with the audiostream review of the mytek. Proper design dictates buffering and reclocking off of it. All inputs feed the buffer so if there is a difference in sound between inputs, I am not willing to spend a dollar on it. But then again these reviewers do not just do a null test and put the issue to rest either. Subjective claims are just that - claims. It is a shame that these are called professional reviews. I see that a firmware update has supposedly resolved the differences in input. Has anyone measured this or performed a null test? What did the firmware update do exactly? Why was it broken before? Did the people who make the Invicta not read the textbook on Digital Audio?