• Registered: 2008-07-07
  • Posts: 44

Topic: Driver suggestion (a small brick) :)

Hello,
I'm facing a couple of problems I'd like to know if is there any possibility to correct this in the driver. Please excuse me if somehow are pilot error smile , but I have to ask.

I have an iMac (pretty new) and run Logic. The interface is a FF800 but I also have an Apogee Rosetta800 (FF800 as master via WC). Logic's audio preferences has a parameter which lets you add a positive or negative delay (in samples) to the recording. In my loopback tests I've found that with the FF800 analogs optimal value is 0; but to properly record a loopback with the Rosetta (via Lightpipe) requires a value of +12 (@44.1). This and the fact that also during playback there is a small time difference between both converters outputs leads to a lot of problems I don't know how to solve:
Can't really use all 16 channels of inputs because 8 of them will be recorded at a non optimal place early or late...  it depends on which setting you choose. only solution I see is move the recordings by hand or change the setting all the time to match the converter you'd choose. I also tried a digital loopback with the value of 0 and it ended recorded early...

Can it be possible to add a delay parameter in the driver to adjust digitals with analogs?. Or split the driver in parts each one reporting its own value.


one more:

I mix in analog and I find disturbing how the outputs are numbered in the Fireface.... In my mixer is channel 9 but in FF800 is 13.... and so on... Is it possible to have an option to rearrange the output numbers in the driver?. I know... I can re-route in Totalmix. smile

I don't know if this is even remotely possible technically, but I'd like to know big_smile

regards

  • Registered: 2008-07-07
  • Posts: 44

Re: Driver suggestion (a small brick) :)

73 views and any answer... ¿Does anybody agree or disagree? smile

  • From: Germany
  • Registered: 2007-04-10
  • Posts: 9,751

Re: Driver suggestion (a small brick) :)

Delay requires internal memory, so not possible...

In any real world recording situation, this theoretical offset is totally irrelevant. Moving a microphone back or forth a few inches will cause more of a difference. I would suggest to just not worry about this at all.

No way to rearrange channels, sorry.


Regards
Daniel Fuchs
RME

Regards
Daniel Fuchs
RME

RME Support's Website

4 Reply by gpiccolini (edited by gpiccolini 2011-10-19 20:37:40)

  • Registered: 2008-07-07
  • Posts: 44

Re: Driver suggestion (a small brick) :)

Ok... Thanks for the kind answer.  I know it's not like its recorded 15seconds late or early big_smile , but the delay I get between converters is 31 samples (more or less 25cm. @ 44.1Khz). Weird thing is: FF800 analog inputs also have to be converted to digital but they do record perfectly on time with a setting of "0", but a digital loop results on sound recorded "early". So somehow the analog input information seems to be reported "ahead" of time. can't this feature be disabled?. maybe with this thing off the problem can be solved.

5 Reply by MC

  • MC
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  • From: Germany/Thailand
  • Registered: 2007-04-06
  • Posts: 25,542

Re: Driver suggestion (a small brick) :)

There is only one value to be reported. Changing this there would still be the difference between digital and analog ports.

Regards
Matthias Carstens
RME

MC's Website

  • Registered: 2008-07-07
  • Posts: 44

Re: Driver suggestion (a small brick) :)

excuse my ignorance and my insistence (I try to understand this), but in cases like mine: where I use digital I/O to connect more converters to record and also mix in analog, wouldn't be beneficial to disable the analog inputs time correction? (if that exists, of course). Then all the converted audio will arrive more or less together... Or any other problem will arise?. Is my understanding that time differences between analog and digital connections are due the time it takes the converter to do their job, in an "all analog" FF800 system all inputs should be at least closer in time if the compensation is Off.
I mean: when recording with lots of inputs at the same time, the delay between converted leads to phase problems between converters (drums, with more than 8 mics, live recording). It may be difficult to solve this, but maybe there's a way to make it a little better with an option in the FF control panel.
smile

thanks for your time

regards

  • vinark
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  • Registered: 2009-06-05
  • Posts: 2,764

Re: Driver suggestion (a small brick) :)

"Then all the converted audio will arrive more or less together..."
No, all AD converters have very different latency. That´s why the analogue ins are exactly on time, it is the only converter of which the latency is known. The only real solution, if you think this is important,  is to have something like a Raydat and 4 identical converters.
Or create a template in logic with the different delays set up and where you record to a track for the right audio path.
Or group mics on one device that need phase coherency. For example the BD and close Snare don´t need it (cause the bleed isn´t phase coherent to begin with), but overheads do.

My guess is that you are blaming the converter delay for a problem that is inherent to multi mic drum miking, phase issues, but they already existed on analogue tape. Sometimes it is only solvable by either moving a mic that causes problems or nudging a track after recording by ear.

Vincent, Amsterdam
https://soundcloud.com/thesecretworld
BFpro fs, 2X HDSP9652 ADI-8AE, 2X HDSP9632
  • From: Washington DC, USA
  • Registered: 2007-08-06
  • Posts: 442

Re: Driver suggestion (a small brick) :)

gpiccolini wrote:

one more:

I mix in analog and I find disturbing how the outputs are numbered in the Fireface.... In my mixer is channel 9 but in FF800 is 13.... and so on... Is it possible to have an option to rearrange the output numbers in the driver?. I know... I can re-route in Totalmix. smile

I don't know if this is even remotely possible technically, but I'd like to know big_smile

regards

Several others, myself included, have requested the ability to re-order UFX channels, and to disable unused channels.  I think RME said they would work on this, but I am not sure if this is still on their list of features for a future driver/firmware release.

  • Registered: 2008-07-07
  • Posts: 44

Re: Driver suggestion (a small brick) :)

vinark wrote:

"Then all the converted audio will arrive more or less together..."
No, all AD converters have very different latency. That´s why the analogue ins are exactly on time, it is the only converter of which the latency is known. The only real solution, if you think this is important,  is to have something like a Raydat and 4 identical converters.
Or create a template in logic with the different delays set up and where you record to a track for the right audio path.
Or group mics on one device that need phase coherency. For example the BD and close Snare don´t need it (cause the bleed isn´t phase coherent to begin with), but overheads do.

My guess is that you are blaming the converter delay for a problem that is inherent to multi mic drum miking, phase issues, but they already existed on analogue tape. Sometimes it is only solvable by either moving a mic that causes problems or nudging a track after recording by ear.

Hello, I'm not blaming anything, I'm writing about a problem I have. It doesn't stop my work to be done, but sometimes forces me to workarounds. I was suggesting that MAYBE disabling the FF800 driver compensation for its own AD will possibly make other AD converters to align better with FF800 ones. I'm aware that it's not a good idea to play or record a stereo track thru different converters, but 31 samples early or late is around 1ms (@44.1) which is roughly most AD converters latency. If I get a 5 samples of difference I'll start to call it "negible", although is my believing that the recording has to be done at the exact place, not close to it.

I only wrote about this to have a small discussion and see if things can be bettered. I like RME a lot esp. for their rock solid drivers and support  smile

regards

10 Reply by MC

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Re: Driver suggestion (a small brick) :)

> I've found that with the FF800 analogs optimal value is 0; but to properly record a loopback with the Rosetta (via Lightpipe) requires a value of +12 (@44.1).

> but 31 samples early

The latter most probably refers to a digital loopback, which is not the point here. 12 samples sounds more like an expected difference between different converters when connecting them to the FF's ADAT port.

Regards
Matthias Carstens
RME

MC's Website

11 Reply by gpiccolini (edited by gpiccolini 2011-10-20 16:14:10)

  • Registered: 2008-07-07
  • Posts: 44

Re: Driver suggestion (a small brick) :)

Matthias:

these are my test values for analog loopbacks @ 44.1 in Logic 9.1.5 (Lion)

With a setting of "+12" in Logic (Rosetta out)
Rosetta: 0
Fireface: 31 samples late


With a setting of "+12" in Logic (FF800 out)
Rosetta: 19 samples early
FF800: 12 samples late

With a setting of "0" in Logic (Rosetta out)
Rosetta: 12 samples early
FF800: 19 samples late

With a setting of "0" in Logic (FF800 out)
Rosetta: 31 samples early
FF800: 0

recording an external signal on both also results on a 31 samples difference.

I love your sense of humor on my new "title" big_smile
EDIT: oops. it changed again!... big_smile  still like it.