The Absolute Sound "review" of USB cable reads suspiciously like a press releaste


I mean c'mon—can't you even throw in a few according-to-the-manufacturer's?

http://www.theabsolutesound.com/articles/nordost-purple-flare-usb-cable/?mc_cid=1f41b2b3b4&mc_ei...
john_g
The arguments are dissimilar.
This is not about whether a digital format produces a perfect reproduction of an analog source or otherwise.
This is about whether the USB data transfer protocol is bit perfect as long as the interface is spec compliant- including the transmitter and receiver.
The answer to the latter question is yes, it is.
The answer to the former question is far more complex.
There is some possibility that the USB can introduce noise through the ground connection. The USB receiver can be designed to eliminate the possibility of ground loops. However, sometimes the problem does occur.

By the way, to put this in context, my system is tri-amped with a sub woofer and a pair of slightly modified ML Montis, The electrostatic panels are driven by one of the following- Rogue M180s, Hypex Ncore 400s or a Benchmark AHB2, depending on my whim. The non electrostatic units are all driven by DSP equalised class D amps.
The preamp is a modified Hovland HP100 or a home made phono amp driving a digital ADC/DAC- the RME ADI-2 PRO FS. My cables are all home made (except for the USB ;-))
My cartridge is a Miyajima Madake. I also have many 15IPS 1/4" 2 track tapes- safety masters or similar- that I play on a Otari MX50.
I have digitized many LPs/tapes and I play them back with the RME device using a USB connection.

Actually it’s the same argument. The CD argument is that digital data encoded on the CD cannot be changed and that laser servo mechanism + error correction together ensure that the 1s and 0s maintain their integrity all the way to the DAC. It’s called the 1s and 0s argument. It’s the same argument used to “prove” that there’s no difference among digital cables, that 1s and 0s are being transmitted by the cable so aren’t affected by rf or vibration like analog signals are.
Perhaps you view it that way. I do not. CD readback is imperfect because there are mechanical and optical imperfections in the recording and playback processes that result in timing issues and there also is stochastic jitter. These processes are intrinsically more complex than the rather simple USB interface impairments.
The attached CD data recovery circuitry is tasked with the restoration of the near ideal bit sequence that then is applied to the DAC. 
There's plenty of room for the introduction of timing errors/jitter in that process even if the result is ultimately bit perfect.
Ideally the DAC will retime the input data to restore a pristine, low jitter, bit perfect,  data sequence for conversion to analog.
Incidentally, the same kinds of circuits/techniques are used to recover data for high speed data links such as is used on the backbone of the internet. The jitter requirements for those applications are orders of magnitude lower than the needs of audio and although the noise bandwidths are different the issues remain the same, particularly as modulation of the phase and/or modulation of the amplitude is used to increase the data capacity.
“There’s plenty of room for the introduction of timing errors/jitter in that process even if the result is ultimately bit perfect.

“Ideally the DAC will retime the input data to restore a pristine, low jitter, bit perfect, data sequence for conversion to analog.”

>>>In my view the damage is done immediately and irrevocably as soon as the laser reads the data. The primary reasons why the CD playback process is imperfect is due to scattered laser light getting into the detector and vibration of the CD player and CD itself. The nanoscale geometry involved - laser beam width, pit depth distance from laser to the CD metal layer - makes the job of the servo mechanism, especially with all the vibration that is occurring, impossible. You get what you get.

The USB cable argument is probably more similar to the digital cable argument. Or so it would appear.