• Registered: 2011-02-08
  • Posts: 18

Topic: adat device out of sync with ff800

i took a mono signal, split it with y cable, and ran it into my fireface and the adat device (behringer ada8000) that's supposed to be the slave, then recorded. when i looked at the waveforms they were off by about 30 samples. when i summed to mono you could hear it. very obvious.

so what's going on here?

the ff has a solid green light for adat 1. i thought that meant sync. i'm using 2 toslink cables. behringer ada8000 out to ff in. ff out to ada8000 in. ff is set to internal.

the only thing i can figure is the converter paths take 30 samples longer in the ff.

  • From: Germany
  • Registered: 2007-04-10
  • Posts: 9,776

Re: adat device out of sync with ff800

You are confusing sync and sync... Clock sync is not synonymous with perfectly synced time positions, different converters do take different lengths of time for conversion. 30 samples seems quite a bit of a difference, and I would tend to assume the FF is "faster", but who knows - I haven't tested the ADA.

Anyhow, nothing to worry about.

Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

RME Support's Website

  • Registered: 2011-02-08
  • Posts: 18

Re: adat device out of sync with ff800

i guess i am confusing sync with sync. haha. so you are saying this is normal? they are in sync but off by a constant.

yeah, i would think the ff would be faster too. i can double check that one.

so it seems like i should figure out what this time difference is and then manually move the the tracks to match. for me this means moving 8 tracks over 30 samples. 30 samples is pretty close. might be 29 or 31 though. but when you sum the 2 tracks to mono you really hear comb filtering. not good.

i can test the manual move with some pink noise and confirm  comb filtering is gone.

good to know this is normal. thx.

  • From: Germany
  • Registered: 2007-04-10
  • Posts: 9,776

Re: adat device out of sync with ff800

You only need to worry about or consider correcting this offset if you only record identical signals on all channels and then sum them. Else, 30 samples is equivalent to about 20 cm distance between microphones.

If you are recording separate signals, there will be no comb filtering.


Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

RME Support's Website

  • Registered: 2011-02-08
  • Posts: 18

Re: adat device out of sync with ff800

good point. there are some drums. maybe 4-8 tracks. i think i'll feel better just making the adjustment. should be pretty fast.

  • From: Germany
  • Registered: 2007-04-10
  • Posts: 9,776

Re: adat device out of sync with ff800

If you record all the drums with one converter and the rest with the other, you will not notice anything... But of course there is nothing wrong with aligning tracks, if you wish.


Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

RME Support's Website

  • Registered: 2011-02-08
  • Posts: 18

Re: adat device out of sync with ff800

cool you guys. and thx for the quick response. i'll try and keep the drums on one converter.