Hi
The jitter on the BDP 2 and 3 has been measured at less than 15 picoseconds so I am not sure what would cause a cable length to affect jitter?
james
Hello James,
I'm still not sure with respect to your 15 ps comment (honestly). The last time you mentioned about the outputs being transformer coupled. I did some reading on this as well since and about AES recommendations. I tried to find about my current DAC (Dangerous Music Source) as well and it was Direct Coupled. Chris Muth was behind the design for this and the rest of the gear. He does this for all the mastering gear as well and the new Convert-2.
"No transformers that color your sound or filter caps
that smear stereo. Instead, DC coupling with a custom
instrumentation grade power supply for simple, electronic
elegance. Bandwidth from DC to light."
I tried to find out about direct coupling and if that had any impact on the digital side, and couldn't find any.
This is what Steve Nugent had written on the first page:
"The optimum cable length will depend on the risetime of the signal. The faster the risetime, the shorter you can make the cable. Very short cables such as 0.5m are to be avoided because the reflection from the destination makes its way back to the source just as the destination is sampling the transitioning edge. This creates jitter. Therefore, make it as short as possible, given your risetime, but long enough to avoid the first reflection (there are attenuated second and third reflections)."
The link to the forum I posted above talks about it in more detail and the 3 scenarios. There was also discussion on the kind of jitter in some of the previous pages.
It very well may be just my DAC, which I've accepted from the start.
I did more tests with AES (Grimm TPR 2 feet, TPR 4 feet, Mogami 3173 10 feet, 3173 18 feet). I disabled all the other digital outputs as well. Database and everything disabled. Only WAVs. To keep things as tightly controlled as possible with the lowest system activity. I used Jitterbugs and Flash drives as well.
There is a sense of ease and improvement in locating the soundstage with the longer cable. Again, I was using the 4 feet for past few months and it was livable and better than 2 feet.
If I had the BDA-2 or BDA-3, I'd be doing with that as well to confirm.
Out of curiosity James, what length of cables do you use for AES? Also, do you happen to have a long AES cable (around 15-18 feet)? I would love to get your impressions if possible with the longer cable on a day you are free. BDP-X to BDA-X.
It's not a serious issue anymore for me, with having made other improvements, but I'm still curious and puzzled about this topic. Cheers.