DS with a headphone amp - crossfeed


#1

Hi @tedsmith

I’ve been trying crossfeed (Bauer stereophonic-to-binaural DSP) with my headphones setup with my DS.

I ran your bitperfect test with crossfeed enabled and I get the green check mark showing on the DS screen.

Obviously it would be silly to ask if I should be using crossfeed - that’s so highly a personal preference.

But I’ve always followed your advice about DSP (like the PC software doing upsampling to DSD128) and always turned DSP off that fails the bitperfect test.

But crossfeed is one DSP that doesn’t look like it affects the bits.

Unlike other forms of DSP that fail the bitperfect test, is there any downside that you know of with using crossfeed for headphones listening, in terms of the DS and the processing it itself does.

And a much less ‘how long is a piece of string’ question: are you a fan of the Bauer crossfeed DSP for your own headphones listening yourself or not really?

Cheers in advance


#2

Any DSP that doesn’t change bits isn’t doing anything.

The confounding thing in this case is that the bitperfect test is done using a mono signal. In retrospect perhaps it should have used stereo. Since both channels are identical any linear crossfeed will leave things alone (after all you probably want things that are centered to remain centered in most crossfeed DSP algos.)

A crossfeed is pretty benign for PCM signals, but not so much for DSD.


#3
Ted Smith said

In retrospect perhaps it should have used stereo.


Hi Ted, I thought I may have seen a link posted to the stereo 24/192 bitperfect test but can’t find it now.

Is there a chance it can be posted to the Downloads section or was the file size the issue?

Or a Dropbox link or similar, if possible

Cheers in advance


#4

There isn’t a test like you want available at this time. The (downloadable) stereo test is merely the same exact samples in both channels which isn’t what you need. As I mentioned, for your case I needed to write a slightly different test that relied on two specific but different signals in the two channels. It didn’t cross my mind at the time that 1) some players have trouble playing a mono signal and 2) that there were cases where the errors in one channel exactly balanced the errors in the other channel. I may address this in a future release (after I figure out how to keep a new test file from causing the old test code to fail and visa versa.)


#5
Ted Smith said There isn't a test like you want available at this time.
Not a problem, thanks for the clarification.

#6
Hi @tedsmith

I’m trying a Toslink source and it passes the 24/192 mono bitperfect test (no DSP and no crossfeed in use here).

Does the DS Toslink input support DSD64 via DoP, since 24/192 is working?

Or is DoP via Toslink disabled by the DS?

Cheers again


#7

TOSLink is “wired” just like S/PDIF or AES/EBU - if the hardware supports 24/176.4, 24/192 or DSD64 (via DoP) the software does. I have TOSLink cables that don’t do anything above 24/96, a couple that only handle 24/176.4 / DSD64 and one that does 24/192.


#8
Ted Smith said

TOSLink is “wired” just like S/PDIF or AES/EBU - if the hardware supports 24/176.4, 24/192 or DSD64 (via DoP) the software does.


Thanks Ted, got it working now with DSD64 via DoP. Had to fiddle with the software to find the DoP settings.

Sounds fantastic! But you already knew that of course ! :slight_smile:


#9
Ted Smith said

TOSLink is “wired” just like S/PDIF or AES/EBU - if the hardware supports 24/176.4, 24/192 or DSD64 (via DoP) the software does. I have TOSLink cables that don’t do anything above 24/96, a couple that only handle 24/176.4 / DSD64 and one that does 24/192.


Would you please share with us which brand(s) of TOSLink can handle the higher data rates?

I’m one whose still convinced that my worst enemy is interference coming in via conducting connectors.


#10
Peter said

Would you please share with us which brand(s) of TOSLink can handle the higher data rates?

I’m one whose still convinced that my worst enemy is interference coming in via conducting connectors.


It’s not a brand of any single component of TOSLink that matters, having a squared off end of the optical cable that’s well polished probably maters the most - Your odds of good termination of the optical cables probably goes up with he price of the cable. But I know from personal experience that modestly priced cables (< $100) from people like AudioQuest work - you don’t need costly glass cables but more need carefully built cables.

The specific transmitter matters too, but in my limited experience most of the ones out there work at at least 24/176.4k with a modest cable.

The cables that fail to work here are the kind that come with your VCR/Cable box/DVR, etc.