Logitech Transporter out of sync with EMM Labs DAC6e SE word clock


Good day ~

I’ve posted about this issue in another discussion, but figure I’ll start one here specifically for it.

I recently purchased an EMM Labs DAC6e SE, and got it hooked up to my Logitech Transporter earlier today. I’m outputting PCM data over AES/EBU and have slaved it to the DAC6e’s word clock via BNC. The DAC locks to the signal, reporting no errors on the front panel, but is putting out loads of crackling sounds along with the music. I can then go in and set the Transporter as master and the DAC6e to lock to the external clock, and the crackling is gone. One of the reasons I purchased the DAC6e was that I could utilize its (I’ll assume) superior word clock; without it, I’m only adding jitter to the equation, thus - in my humble opinion - negating its use.

There are a few old threads out there on the Slim Devices forum, but there is no solution even stated; but the fact that things are out of sync seems to the be issue. I’ve left a voice message for EMM Labs; as the Transporter is no longer supported I can only look to the forums, which I’ll be posting this identical information to shortly.

Anyhow, if you have any thoughts or suggestions, please let me know.

Thanks, as always, for your time.

~ Mark
ballywho
After looking through countless forum entries throughout the entire day, I’ve come to the conclusion that, unless there was one (or maybe a few?) firmware updates that resolved this issue, then this is a lost cause.  Of course if you know of anything at all, please do chime in.  If I don't hear back in several days, the DAC's going back out for sale.  :/
Sorry but passing clocks around is an 80's solution that never worked very well. Jitter is a inherent issue with clocks and signals, The best approach is an asynchronous DAC that simply rejects jitter - however do lots of research because many DACs add their own jitter through PLL adjustments which can be far worse than random jitter.
I’ve come to the conclusion that the Transporter’s word clock input (and/or associated software) is simply not functioning correctly, and that there’s nothing wrong with the DAC6.  Considering how much I really do love the Transporter, and was just curious about older DACs (even though I didn’t quite take that exact route), the DAC6e SE is going back out on the market.  That may sound hasty as all get-out, but I have no interest in combing the planet for a fix.

Seems to me you have to enable it at the Transporter, which makes sense.  The free-running clock in there has to be synced to the word-clock, so it may be disabled as default.

I have used it before and it did work with my products years ago.


Steve N.

Empirical Audio

BTW, this is not about passing around clocks.  This word-clock is used to synchronize the source clock so that the stream coming into the DAC is synchronous with the local low-jitter fixed frequency MASTER clock.  Perfectly good solution that can yield very low jitter.


Steve N.

Empirical Audio

I originally posted this issue a long time ago. Solution was to make sure to turn off display when playing and to convert to pcm at server I believe.