True round trip latency for Scope cards - Ableton problem

[sodiumcycle]

How can I find the true round trip latency for the Scope card? I need to override the Ableton automatic latency adjustment with the true roundtrip value.

More info:
I'm using Ableton with external gear (compressors, eq) and need to adjust the latency of recorded tracks by setting the sample nudge of the processed track to get it to line up to the recorded track (parallel compression.) The latency reported by Scope does not match the latency reported by Ableton. I'm getting bad phasing when trying to line up processed tracks with dry tracks using the sample adjustment reported by either Scope or Ableton.

[maky325]

It happened to me before. I can't recall how i fixed it i only want to say that it's possible to align them properly. Someone else will jump in. The thing is (if memory serve me well) that some of scope devices or mixers add slight delay for DSP processing. Several samples (enough for phasing issues). Now i can't recall how i calculated it properly but when i was done it worked.

I think there are tools here at the forum to "ping" correct delay. Sorry i don't have Scope anymore but it's possible to do it.

p.s. If nothing help try to run Cubase demo, or Studio one demo. They have external hardware configuration tool with that "ping" option which calculate real delay. Once when delay is reported in these applications you can put same delay in Ableton and it will work.

[astroman]

for parallel compression, let alone drums... you can't get it right automatically - just forget about it
as maky wrote, each plugin may slightly vary, for example Transient Designer adds 41 samples.
(the biggest offset I noticed, but 3 to 6 samples isn't uncommon)
that's perfectly okay with a realtime system - it put's you into control
for critical stuff I simply measure the real figures for the roundtrip once.
It's not even advisable to adjust everything to one single point in the attack curve...
(just read that in the explanation about the Slate Trigger drum replacement stuff and it made perfect sense)

cheers, Tom

[next to nothing]

I just checked the real roundtrip ASIO latency for my cards, using http://centrance.com/downloads/ltu/ .
You can insert whatever between asio in and out and see what results you get.


44100Hz:
3ms = Measurement results: 258 samples / 5.85 ms
4ms = Measurement results: 386 samples / 8.75 ms
7ms = Measurement results: 642 samples / 14.56 ms
13ms = Measurement results: 1154 samples / 26.17 ms

48000Hz:
3ms = Measurement results: 258 samples / 5.38 ms
4ms = Measurement results: 386 samples / 8.04 ms
6ms = Measurement results: 642 samples / 13.38 ms
12ms = Measurement results: 1154 samples / 24.04 ms

96000Hz:
1ms = Measurement results: 258 samples / 2.69 ms
2ms = Measurement results: 386 samples / 4.02 ms
3ms = Measurement results: 642 samples / 6.69 ms
6ms = Measurement results: 1154 samples / 12.02 ms

[dawman]

Thanks NTN.
THat's an accurate tool and shows different measurments different than Reaper shows.
I always thought .07 msec @ 64 samples was pretty fast.
this tool shows round trip of 1.8/96k, and 2.4msec/64 samples/48k, my new live setting so I can run Solaris vis the AES/EBU I/Os.

Coolness

[sodiumcycle]

Thanks guys. That is just what I was looking for.

[mausmuso]

Sodium,
I suppose you are aware that the STM 2448 channels each have sample delay setting that can be adjusted?
I use it sometimes to correct/tighten up track latency.
Not sure if it will fix your issues though?
maus

[astroman]

yeah, a cool feature that's often overlooked...
would be even smarter with an additional milliseconds offset - for Asio roundtrips the range is too small
so it needs a 'regular' delay set 100% wet (bells 'n whistles off) and the sample delay for fine tuning

cheers, Tom

[jksuperstar]

Since you are in essence making a full circle, round-trip of audio, it shouldn't matter where you are measuring from/to.

So, there's a Scope device that you place, and it'll measure round trip from any dsp, out to wherever, and back. So you can measure out to your daw and back. Use it between DSPs, to outboard gear, or your DAW...

With good vibes from tgstgs--
http://forums.planetz.com/download/file.php?id=8001

(originated from this thread: http://forums.planetz.com/viewtopic.php ... ck#p270549 )

I think...