Changing the mute fade speed

Zor · January 25, 2019, 9:49am

I would like to know if there’s a parameter somewhere to change the speed at which the gain if changed when changing the mute/solo state of a track ? I would like to have it very slow (like 1 or 2 seconds).

x42 · January 25, 2019, 9:58am

There is no configuration for this. The slope is hard-coded (approx 1/25Hz = 40ms exponential fade).

x42 · January 25, 2019, 10:16am

PS. It may be a good feature request, something to add in a future version.

right now, you could edit the source and re-compile (but that’ll also affect other fades, not only mute):

github.com

Ardour/ardour/blob/master/libs/ardour/amp.cc#L258


		return initial;
	}


	// if we don't need to declick, defer to apply_simple_gain
	if (initial == target) {
		apply_simple_gain (buf, nframes, target, offset);
		return target;
	}


	Sample* const buffer = buf.data (offset);
	const gain_t a = 156.825f / (gain_t)sample_rate; // 25 Hz LPF, see [other] Amp::apply_gain() above for details


	gain_t lpf = initial;
	for (pframes_t nx = 0; nx < nframes; ++nx) {
		buffer[nx] *= lpf;
		lpf += a * (target - lpf);
	}


	if (fabsf (lpf - target) < GAIN_COEFF_DELTA) return target;
	return lpf;
}

Zor · January 25, 2019, 10:48am

Thanks a lot, I’m currently studying the subject on how to set up a compiling environment, using a linux virtual machine on Windows, to cross-recompile a Windows version of Ardour (unfortunately I have to work on Windows for my other tasks). I will probably need to recompile anyway, as my needs are a bit unusual.
Maybe it would be easier to write a small plugin in LUA to implement this feature (don’t know how to do this either) ?

x42 · January 25, 2019, 11:27am

Depends what you need. Replacing mute/solo logic with a script isn’t possible. But if all you need is a plugin that has an automatable “Mute Button”, that could be a Lua script. e.g.

a-mute

A quick example (based on a-amp) http://paste.debian.net/1062435/ (save to %localappdata%\ardour5\scripts\fade_in_out.lua)

PS. Line 24 lpf = 100 / rate -- interpolation time constant – the smaller the time-constant, the slower the fade

Zor · January 25, 2019, 11:32am

This is exactly what I need.
Thank you very much !