Two years ago, I set out on a quest to understand why certain cables/CD transports, DACs, etc. sound better than others.
One of my long time audiophile friend, who happens to be in high-end audio bussiness for 30+ years and he himself an audiophile told me its partly because of the power supply and jitter. He is no engineer, so he is unable to explain to me why this is the case. What he was telling me was the truth based on his 30+ of experience in the audio business. I was very skeptical then: how is the power supply going to cause an audio circuit to sound better than another? Especially for a CD transport when all it does is moving bits from one medium to another? In audio, the precise arrival of digital audio data to the DAC is very important. You can have two transports outputting the same data bits, but the one with high jitter will sound substantially inferior. Jitter causes earlier or later arrival of the data bits in the data steam. It is a very small timing difference, but as it turns out, human can discern those tiny differences. The typical effect of high jitter is brighter sound, less bass, less sound stage depth. So how is the power supply going to affect the audio circuit? There is noise on our household AC line. On the same circuit, your neighbors may have florescent lightings, motors in electric fans or air conditioners and poorly designed switching power supplies that emit kH of frequencies into the AC line. These noises cannot be filtered by a simple cap or the run of the mill 7805 regulator in the power supply circuit. And yes, the Transporter has super regulator, but unfortunately, it does not have super regulator in the digital circuits. And many other audio gears in our systems do not have super regulators at all. The AC noise has serious affect on how a capacitor or conductive AC and component interconnect cables may sound. This is why audiophiles often change cables and even caps in their gears to fine tune the sound. They are effectively changing to a component that has less/better noise conduction characteristics (ie: less noise being conducted). This would work in one home, but may fail completely when moved to another home, but the set of AC noise in another home is different. So they change cables again. So how is noise going to affect digital circuits? Jitter. Although the buffer holding the data from the TCP protocol is 100% accurate, the output of this buffer will be affected by jitter induced by electronic noise. A steady state electronic noise produce a steady stream of jitter. But a spur of electonic noise will cause more jitter in the circuit. If the packets received via Wifi is in spur due to various reasons (latency, poor signal range, etc.), then more jitter will happen on the output buffer. Going to a wired connection is better, because the packets are coming in at a more steady pace. I believe what we need is a double or triple buffering design with the final output buffer (a very small one) having a very steady stream of input. The circuit designed around this final buffer should be relatively noise and jitter free. Some high end gears are beginning to implement multiple clocks and buffers in their transports/DACs design. PS Audio Digital Lens is one. Some of the latest Mark-Levinson DACs have special purpose input buffers in them. I think Esoteric has triple clocks/PLLs buffers too. -- Kuro ------------------------------------------------------------------------ Kuro's Profile: http://forums.slimdevices.com/member.php?userid=16701 View this thread: http://forums.slimdevices.com/showthread.php?t=74721 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
