I think this test was measuring the clock of the AP1 vs. the other two, rather than the usual S/Pdif output.
That's what I suspected. My clocks are just as good if not better.
I also have a NEL clock that I can put on my Turboclock which measures phase noise at -128dB at 10Hz. When comparing this to my current clock from Crystek, the audible difference is small. The Crystek is -155dB at 10kHz.
AP's specification of 15ps p-p using their WaveCrest I think was done with S/Pdif.
This may be at 10kHz. At 10Hz, the plot puts the RMS jitter at about 500psec, and this is just the clock alone.
I've heard from a few people that using bus power seems to reduce the performance of the AP quite a bit, despite the "regenerative" internal power supply. I'm amazed that the $2900(!) Sonicweld Diverter HR continues to use bus power. They obviously go to herculean lengths to try to clean it up but, why bother with all that when you can just use either batteries or a nice linear supply? I don't get it.
Me either. Whats the point? Make it simpler and then charge $3K??
BTW, I discovered that my new Hynes design actually outperforms LifePO batteries. I put both in the OR4 and compared them.
Do you know of any comparisons of the OR vs. the Berkeley Alpha USB? These are the two I'm most interested in. Even if the Diverter solves all of the USB power issues, the price is so high that it's silly. If you're going to spend nearly $3,000 you might as well just skip the converter altogether and buy a USB DAC.
Agreed. I dont know anyone that has one yet, only the review in July/Aug TAS. Pflaumers background is not really digital design according to the review. Harley compares it driven by a Mac compared to a Lynx card in a PC, which is not interesting or particularly useful IMO. It's really too bad that Steven Stone did not do this review. He would have put it head-to-head with my Off-Ramp 4.
Steve N.