Trying to Re-Amp with Axe-FX and keep it in time. "input manual offset" behavior

thefastener · 05-14-2021, 03:03 PM

Reaper 6.28

Basically just want to re-amp a lot of guitar tracks without having to nudge them into place after the fact. The input manual offset setting seems to have a mind of its own.

Routing all stays internal to the Axe-FX (edit: it is my interface in reaper), no cables, everything is staying USB.

Setup:
• Added hardware send on "click" channel to AxeFX OUT 7/8 (goes to IN USB block in the Axe FX)
• Second channel for "processed" sound set to record IN 1/2 on Axe-FX (OUTPUT 1 block in the Axe-FX)

Basically this tells the Axe-FX to send the "click" through the Axe-FX and record the output of its processing onto another track.

First pass with "Use audio driver reported latency" checked
All Offsets set to 0 samples, 0 ms.

Late by 365 samples as can be seen below

Second pass only change is "Input manual offset" set to 365 samples

Early by 246 samples

Third pass only change is "Input manual offset" set to 119 samples (365-246)

Early by 47 samples

Fourth pass only change is "Input manual offset" set to 72 samples (119-47)

Late by 187 samples

Am I doing something wrong here? If you don't change sample rates or anything else, shouldn't you be able to calculate "Input manual offset" once and it work across projects?

Additional notes:
• on blank projects I can get the offset to line up, but if I open other projects (sample sample rate/audio device) it will mess up the value that i used in the "blank" project
• I also tried this on the portable version of reaper 5.99 and had the same issue.
• The ReaInsert ping method had the same results too.

sonicowl · 05-15-2021, 01:43 AM

When I ping for latency I find it best to put external fx into bypass. Usually that is reliable for me. I wouldn't obsess over it too much. At 44k, being off by 100 samples is around 2ms, which is about half meter of changed distance from source - like if you would move less than meter further away from your guitar amp speaker. Do you notice delayed sound if you make a step away from gutar amp?

thefastener · 05-15-2021, 07:18 PM

Appreciate the response. I guess the problem I'm having is that it seems unstable between projects and sometimes it is perceivable on playback.

Was hoping to find a "fix" to stabilize it so that I could set it and forget it.

dug dog · 05-15-2021, 08:15 PM

Quote:

Originally Posted by thefastener

• on blank projects I can get the offset to line up,

I'm confused. Was the test you illustrated not all done in the same blank project?

thefastener · 05-16-2021, 08:18 AM

Quote:

Originally Posted by dug dog

I'm confused. Was the test you illustrated not all done in the same blank project?

The screenshots above are me trying to adjust an existing project. I've also copied all the tracks over to a new project to try and ensure that the project file isn't messed up.

When I do it in a blank project, I can easily get the correct value, but if I leave the project, go to an existing project, and reuse the same offset, it will not be in sync with the original track.

If I go back to the blank project and use the value that worked, it will no longer sync. Also the value that works on the blank projects seems to be random.

dug dog · 05-16-2021, 09:06 AM

More questions:

Is the Axe your sole audio device/interface?
When you're re-amping, is the Axe acting as both interface and FX processor?

thefastener · 05-16-2021, 12:52 PM

Quote:

Originally Posted by dug dog

More questions:

Is the Axe your sole audio device/interface?
When you're re-amping, is the Axe acting as both interface and FX processor?

I also have a Focusrite Saffire Pro 24 hooked up, but in Audio > Devices I am set to use the Axe-FX ASIO driver. While re-amping, The Axe-FX is acting as both the Interface and "external" FX processor. (It is all handled via USB, no 1/4" cables)

I do have a SPDIF connected from the Axe's Out to the Focusrite's IN, but I only use this to push sound to my monitors. The Word Clock on the Axe-FX is set to "Internal" and the SPDIF out is set to Output 2 (I'm using Output 1 for all of the routing previously mentioned).

sonicowl · 05-16-2021, 02:47 PM

Again, do try the test with Axe in bypass mode. I suspect there is some time based fx (delay or chorus etc) messing with your ping.

dug dog · 05-16-2021, 02:49 PM

Well, we've managed to drill down on the situation a bit more. So that's good.

Lynx_TWO · 05-16-2021, 04:25 PM

Quote:

Originally Posted by sonicowl

When I ping for latency I find it best to put external fx into bypass. Usually that is reliable for me. I wouldn't obsess over it too much. At 44k, being off by 100 samples is around 2ms, which is about half meter of changed distance from source - like if you would move less than meter further away from your guitar amp speaker. Do you notice delayed sound if you make a step away from gutar amp?

Oooo maybe I’m missing something, but I gotta disagree with ya on the 2ms delay not being an issue; it depends on if he’s mixing with another source. For example, take a mono to stereo guitar track and offset the left or right channel by 2ms. You’ll hear the difference. It’s actually a cool trick if you want to push an instrument outside the boundaries of 100% L or 100% R. You are correct in saying you wouldn’t hear a difference stepping 1/2 meter away from his guitar amp, because the act of stepping 1/2 meter away takes much longer than the 2ms of delay it causes

thefastener · 05-16-2021, 06:22 PM

Quote:

Originally Posted by sonicowl

Again, do try the test with Axe in bypass mode. I suspect there is some time based fx (delay or chorus etc) messing with your ping.

I've tried removing FX from all channels and the Axe-FX's chain is strictly routing in and back out, no other blocks. I'm not exactly sure how to bypass beyond that as I'm using my Axe-FX as the interface as well. So any routing is staying internal to the Axe-FX.

sonicowl · 05-17-2021, 12:32 AM

Quote:

Originally Posted by thefastener

I've tried removing FX from all channels and the Axe-FX's chain is strictly routing in and back out, no other blocks. I'm not exactly sure how to bypass beyond that as I'm using my Axe-FX as the interface as well. So any routing is staying internal to the Axe-FX.

I'm not familiar with specifics of Axe-fx. When I use external FX hardware, there is usually a bypass button, which bypasses all fx and sends through raw signal. But I'm working with ADAT rack converters. I guess things can be different with axe, because it is actually your audio interface.