• Registered: 2020-04-25
  • Posts: 8

Topic: Delay compensation for external processing

- RME Fireface 800 v3.41
- RME Totalmix v1.75
- Pro Tools v2024.6
- iMac M1 (2021)
- macOS Sonoma v14.7.1

Hi all,

I have recently been getting back into music production to fill the creative void. My most recent acquisition is a Moog Moogerfooger MF-101 LPF pedal which is used primarily for baseline processing and hard patched from an available analogue output from an Akai MPC Live 2, and then hard patched into an available front panel FF800 line input. I had originally patched the MF-101 pedal into a rear line input, but didn't have enough output level to match my systems dBu, the front panel line input is beneficial purely for the gain pot which allows me to match the systems dBu.

I have recorded the roundtrip latency, and it is roughly 0.250 milliseconds. Enough that it is noticeable, and this can obviously be corrected in my DAW (Pro Tools v2024.6). The Totalmix input channel can be phase flipped, and this obviously makes a noticeable difference, but I'm curious if Totalmix natively supports delay compensation? To be clear, this is purely for monitoring purposes, as when my musical compositions are complete, they are multi-tracked into Pro Tools for final mix down, and latency/phase corrections can be applied.

Any further suggestions to aid the obvious latency observed with external equipment, monitored via Totalmix?

Thanks for the read!

  • waedi
  • DAW Mastermind
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  • From: Swiss Zürich
  • Registered: 2020-12-08
  • Posts: 4,839

Re: Delay compensation for external processing

How did you measured this roundtrip latency ?

Monitoring directly thru Totalmix should not add any noticable latency.
How is the routing of the Moogfooger ? You say this is for the Bassline.
Is this Bassline inside the DAW ?
then of course you will have latency on wich Totalmix can't do any compensation.

M1-Sequoia, Madiface Pro, Digiface USB, Babyface silver and blue
  • Registered: 2020-04-25
  • Posts: 8

Re: Delay compensation for external processing

waedi wrote:

How did you measured this roundtrip latency ?

Monitoring directly thru Totalmix should not add any noticable latency.
How is the routing of the Moogfooger ? You say this is for the Bassline.
Is this Bassline inside the DAW ?
then of course you will have latency on wich Totalmix can't do any compensation.

Thanks for your reply!

Signal flow:

MPC outputs (6x analogue) -
1-5 patched directly into FF800 rear line inputs
6 patched directly into MF-101

MF-101 output (1x analogue) -
Patched directly into FF800 front line input

All signal generated from MPC, no signal generated from DAW then fed into MPC inputs or auditioned along with MPC.

Roundtrip measured by generating internal MPC click track, routed to output 5 + 6. Pro Tools session with two mono audio channels (5 + 6), audio recorded from MPC and waveform transients measured between both tracks (1 sample difference (1 / 44.1 = 0.022 milliseconds)). Both MPC and Pro Tools have the same session configurations (24-bit / 44.1 KHz).

I should clarify, with my various production techniques I usually split a main sample into both a LPF + HPF of itself for creative processing flexibility, in this example the MF-101 is handling the LPF processing and the HPF is performed internally in the MPC. I believe the issue is that when both LPF and HPF are summed together (monitored in Totalmix) there is phase coherence issues due to the very small (0.022 milliseconds) latency offset generated by the external MF-101. This can all be corrected during mix down in Pro Tools, but before this happens and I am composing a project I am monitoring the MPC outputs (x6) via Totalmix.

4 Reply by waedi (edited by waedi 2024-11-25 09:30:04)

  • waedi
  • DAW Mastermind
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  • From: Swiss Zürich
  • Registered: 2020-12-08
  • Posts: 4,839

Re: Delay compensation for external processing

A click track from MPC is routed to stereo output 5/6 and the recorded tracks 5 and 6 having one sample difference in ProTools ?
Why sending a click track to stereo out ? Why not one mono signal ?
The MPC seems to play out this track on the two channels with a latency of one sample on one of these outputs.
Play one mono track and the problem is gone.

M1-Sequoia, Madiface Pro, Digiface USB, Babyface silver and blue
  • Registered: 2020-04-25
  • Posts: 8

Re: Delay compensation for external processing

waedi wrote:

A click track from MPC is routed to stereo output 5/6 and the recorded tracks 5 and 6 having one sample difference in ProTools ?
Why sending a click track to stereo out ? Why not one mono signal ?
The MPC seems to play out this track on the two channels with a latency of one sample on one of these outputs.
Play one mono track and the problem is gone.

Internal click track or an imported click track file (programmed) has the same results. My calculation was wrong: 1 sample / 44.1 = 0.022 x 1000 = 22.67 ms

I don’t think you understand the issue. It’s essentially phase coherence due to the 22.67 ms delay with the external analogue processor. This is only an issue with Totalmix monitoring i.e. routing direct inputs to direct outputs, and won’t be an issue during mixdown due to DAW delay compensation. Strange that Totalmix doesn’t have delay compensation per input channel.