Quote:This still all boggles my mind, because I came from the "bits is bits" mentality, and a USB hub (Regenerator) and changing a power supply on said regenerator shouldn't make a difference. But it does. I've even gone as far as doing the PS Audio "bit perfect" test on the DAC to prove that with and without the Regen, the bit's are technically the same.
Quote:Seems the whole computer/USB chain has the potential to introduce noise at each link. This thing works on one of the links.
I don't know if I got this completely right or if any of this makes EE sense, but I do know it sounds gooder.
Being a EE for 30+ years, I hesitate to comment on this...mainly because my hearing is not so great any longer and "differences" have to be pretty extreme for me to notice. Volume changes and noise are easy but quality of reproduction, etc. are not.
So I will limit my comments to this:
Bits are bits, but lots of "unwanted stuff" can be brought along with the "wanted stuff" (bits). The transmitters, receivers and auto-correction codecs used for most hardware links like USB, Ethernet, I2S, etc. have become so immune to out-of-band noise (data/clock, tx/rx band, not audio band) that the reconstruction of the data itself is almost always bit perfect at the receiving end. If the link signal quality is so poor due to cable length, poor connections, poor termination, impedance mismatch, interference, etc., that the data can't be reconstructed near perfect, then all sorts of bad things happen and more than likely the result will be audibly awful or even not recognizable enough by the DAC for playback. So that's probably NOT where this type device is helping, in most reasonably decent setups.
However, the "unwanted stuff", even the seemingly not harmful to the data stuff, still has to be disposed of (filtered, etc.) or it just continues to pollute the analog resultant, gets amplified more than once up the chain and based on how good the reproduction equipment is we hear it manifested in untold number of ways.
So, if you can clean up the waste, even the waste that seems to have no effect on the data accuracy, before it gets to the end, even perfect looking data "could" be made to sound better. And in the case of USB this also applies to the power transfer, if it's used, probably even more as that tends to be unimportant and gets overlooked in other uses for USB (non-audio).
Maybe a weak analogy would be cleaning up muddy water. The H2O itself (bits) is still in there in pure form. The regen is a course filter that takes out the worst of the mud, even to the point of the water looking clean and clear, but there's still something remaining that makes it taste funny. Then the DAC and it's circuitry are free to fine-filter out the bad taste without having to clean out the mud....ahhh, maybe not that simple! lol
I'm not saying the regen is just some noise filter but it may be helping to reduce the things that can create more noise or that allow more noise and artifacts into the system. JMO. YMMV. WTF...