LinuxMusicians

Hi,

I am trying to use my Launchkey Mini with Hydrogen, which then goes to Ardour with Drumgizmo.

However, the latency is sending my head funny. I tried the amazing rtcqs script, and followed most of the tips there (not got around to Spectre/Meltdown and Power management ones). I'm on Fedora, which is Pipewire of course.

I had to put Hydrogen into ALSA mode, then it sees my USB midi controller. I then can put Ardour in ALSA mode, and use Ardour MIDI mapping to map the Hydrogen output to the Drumgizmo track.

It all works, but the latency is bad. I only want this to record rough beats which I'll then use to flesh out programming with the mouse on Hydrogen, but I have to mute it and just go off the sound of my fingers on the pads, or I go mad haha.

Any tips? Is Alsa the way, or should I be trying with JACK on Pipewire?

I used a similar setup: An Alesis Crimson II was recorded by Ardour, Ardour triggered the samples of hydrogen. This was done under Jack. The only time i really had some kind of latency-trouble was, when the samples theirselves started a few msec later, there was a pause of about 3 to 5 ms before the sound started in the sample. Because hydrogen was the only reason for still using jack, i'm running now the hydrogen samples from lsp-sampler, completely inside Ardour now with ALSA only.

With the setup
Controller->Hydrogen(midi)->MusE with DrumGizmo

using audio driver Alsa will give me noticeable latency.
Using audio driver Jack sounds tight as a nun's arse.
For midi I use Alsa connections in both cases.

There's no Pipewire on my system.

Edit: simultaneously recording the midi signals Controller->MusE and Controller->H2->MusE exposes a ~ 5.2ms delay in the second signal. Decreasing my Jack buffer size decreases this delay.

How low did you go with the Jack buffer size?

Looks like you have to do pw-metadata -n settings 0 clock.force-quantum <buffersize> in Pipewire land.

I tried it, still seems delayed to me although I don't know how to measure it. To do anything useful I find I have to take the headphones off and record the beat just hearing the tap of my finger on the pad. Maybe its just me.

crustypants wrote: ↑Fri Apr 12, 2024 8:48 pm

How low did you go with the Jack buffer size?

Looks like you have to do pw-metadata -n settings 0 clock.force-quantum <buffersize> in Pipewire land.

Seems the relative latency depends on Jack's period size, not the number of periods per buffer, so for my default setting of 256/2 48kHz, this gives a delay of at most 5.3 ms, which coincides with my measurements of at most 8 midi ticks difference (at 768 ticks per quarter note/120bpm).

crustypants wrote: ↑Fri Apr 12, 2024 9:33 pm

I tried it, still seems delayed to me although I don't know how to measure it. To do anything useful I find I have to take the headphones off and record the beat just hearing the tap of my finger on the pad. Maybe its just me.

Maybe an idea to route your drumpad controller to Ardour/DrumGizmo and Hydrogen in parallel during recording? And during playback switch DrumGizmo's midi input to Hydrogen's midi output?

Did you try different sync-methhods, jack sync vs MTC?

I tried straight into Ardour skipping out Hydrogen. Still dreadful. That tells me something, maybe its Drumgizmo. I also tried both with ALSA and Jack backed. Both are on Pipewire of course being Fedora.

crustypants wrote: ↑Sat Apr 13, 2024 9:09 pm

I tried straight into Ardour skipping out Hydrogen. Still dreadful. That tells me something, maybe its Drumgizmo. I also tried both with ALSA and Jack backed. Both are on Pipewire of course being Fedora.

How's the midi response in Ardour? Just record some midi signals in an otherwise empty project, in time with an internal (to the DAW) metronome.

How's Hydrogen's response if you use it by itself?

crustypants wrote: ↑Sat Apr 13, 2024 9:09 pm

I tried straight into Ardour skipping out Hydrogen. Still dreadful. That tells me something, maybe its Drumgizmo.

Check out this thread on Ardour forum, it could be the same issue. https://discourse.ardour.org/t/drumgizmo-latency/110139

So far just a workaround, no real solution.

Piergi wrote: ↑Sun Apr 14, 2024 10:01 am

crustypants wrote: ↑Sat Apr 13, 2024 9:09 pm

I tried straight into Ardour skipping out Hydrogen. Still dreadful. That tells me something, maybe its Drumgizmo.

Check out this thread on Ardour forum, it could be the same issue. https://discourse.ardour.org/t/drumgizmo-latency/110139

So far just a workaround, no real solution.

Seems obvious if you enable timing humanization that this must introduce latency? How else play certain notes early?

But yeah, maybe OP has timing humanization enabled. The delay this causes with live playing can't be corrected by any DAW's latency compensation.

Hmm ... yes, timing humanisation ... I'd thought of that already. Nope. No way was it something so daft and obvious ...