Allow finer control for crossfader curve adjustments

[jus]

<Quote>
Unfortunately, the crossfader curves are not hard enough for which reason it's really difficult to do scratches like the crab scratch.
Would be awesome if there will be an option to adjust the curve like in the picture.
</Quote>

<Quote>
You also need a crossfader curve somewhere between Constant Power and Slow Fade.
Not exactly sure what good the Linear/Log slider is for, as it seems not to work correctly. Usually you want one slider for the curve of each side, plus a slider for where the max in/out spot is. So four sliders if you want it fully adjustable. At least two if you can live with both sides being the same.
</Quote>

Wishlist bug based on forum feedback:
http://mixxx.org/forums/viewtopic.php?f=1&t=2824
http://mixxx.org/forums/viewtopic.php?f=1&t=2721&p=10237&hilit=crossfader%20curve

[jus (jus)]

I may add some additional resources for reference.

Evolution of the DJ Crossfader - Great read with detailled curve slopes
http://www.rane.com/note146.html

Various crossfader curves in Ableton Live explained
http://www.djinvisiboy.com/2011/08/how-to-dj-ableton-live-the-crossfader/

Some formulas for different sets of crossfader curves
http://math.stackexchange.com/questions/4621/simple-formula-for-curve-of-dj-crossfader-volume-dipped

[Mauritz (mauritzcr)]

Mixxx needs features like this program that currently runs with Winamp, I have tried it and was amazed at its cross-fading abilities.

http://www.sqrsoft.com.ar/index.php

Crossfade - Adjustable working range, 0% to 100% of the mixing buffer, initial(fade-in) and final(fade-out) level control.
Crossfade curve control (non-lineal)
Individual setting for normal crossfade, fade-on-skip/stop and fade-on-seek.

Signal analyzer - It allows crossfade point shifting by signal level. Trigger level from -1dB to -60dB.

Gap Killer - Adjustable trigger level from -6dB to -60dB. Individual settings for rise and fall edges of the track.
Smooth cut to prevent clicks on some tracks with high DC bias offset.

It automatically puts the beats over each other and sounds flawless

[Fringe Logan (clovernine)]

Please we need this feature, it's a vital point of a mixing program (crossfader is the center of the mix !!!)

So please add this feature !!! (and a REVERSE setting for the crossfader too)

WE NEED THIS REALLY !!! WE CAN'T SCRATCH WITH MIXXX, even if the timecode support is very good the crossfader is unusable.

It's not a fast cut, not a slow cut, nor a cut.... IT'S A FADE !!!!

Look at this thread on the mixxx forum for more details :
http://www.mixxx.org/forums/viewtopic.php?f=1&t=4242

[Fringe Logan (clovernine)]

1 - Put a Reverse crossfader option (Used a lot by scratchers but not that much needed)
2 -----> Let us adjust the curve/sharpness of the crossfader
- CROSSOVER POINT SLIDER : point of the crossfader when the 2 decks are mixed together (Cut in).
- SHARPNESS SLIDER : Something that let us get from (SLOW FADE) to (FAST CUT)

But for now, to allow user to scratch (just change the crossfader curve in the "FAST Cut" setting to a sharper one (like the one in the attachment)
We will scratch, and you will have time to work on the more customizable settings.

PLEASE. Thank you

[jus (jus)]

We have already gathered some good ideas.

The current crossfader behavior in Mixxx can be an issue for some specific mixing styles as long as you DONT use external hardware mixers. If you have a good scratch mixer that allows you to control your crossfader curve signal it`s fine. In the classic vinyl control setup, you`ll override the internal mixer and route the audio to your external mixer, which itself determines the sharpness of the fade. See http://mixxx.org/manual/latest/chapters/setup.html#turntables

The reverse crossfader option has been implemented and will be available beginning with Mixxx 1.11beta2, which should arrive soon. See https://bugs.launchpad.net/mixxx/+bug/829533

Nonetheless Covernine has a valid point in #4. It seems to me that changing the setting in the crossfader preferences does effectively nothing. This has been reported before by uklotzde, whose VCI-300 script crossfader changes do not work.

Was the patch from https://bazaar.launchpad.net/~mixxxdevelopers/mixxx/release-1.11.x/revision/3216 supposed to fix crossfader issues?

[Daniel Schürmann (daschuer)]

A tiny addition: Alban has prepared a patch that deals with a external Mixer setup Bug #970965 We should consider to put it upstream.

[RJ Skerry-Ryan (rryan)]

We should determine if the crossfader curves are working as intended or broken. In either case it sounds like if our crossfader is not useful for scratching then that needs fixing.

[Richard (redguyrichard)]

Just installed Mixxx 1.12 Beta available and it's amazing. However this issue is still not resolved. (I'm surprised it hasn't achieved more attention given it's such a fundamental requirement of even basic scratching, and I assume it's relatively easy to fix). I noticed there is now a scripting engine for controllers. Hopefully this can be used to resolve the issue (translate all crossfader positions to dead centre apart from either extreme left or right). However when I tried to create a script I got a BSOD!

I'm sure this must be a quick fix and it seems a shame to cut Mixxx off (no pun intended) from the scratch community when so much amazing work has gone into making it work so well!

...my fingers are crossed!

Thanks for putting such a great piece of software together guys (n gals?)!

[Daniel Schürmann (daschuer)]

Would it be the right solution just allow to continue the slider in the xfader preferences?

This should be indeed a relative easy to fix we have to increase the maximum value of the "xFaderCurve" co.
https://github.com/mixxxdj/mixxx/blob/da0f31cd220c3ad878367a5abe14044812afeb44/src/engine/enginemaster.cpp#L144
And tweak the preference slider:
https://github.com/mixxxdj/mixxx/blob/3f854c1674084609497036ba92e1605a43fb492f/src/dlgprefcrossfader.cpp#L202

A insane value of 30 might work.

> However when I tried to create a script I got a BSOD!

The famous BSOD where you have to restart your computer?
This must not happen, and indicates a serious driver problem.
Please file a separate bug for it. Thank you.

[Daniel Schürmann (daschuer)]

This depends on Bug #1482163

[Daniel Schürmann (daschuer)]

The xFaderCurve is changed from 1 ... 9 to 1 ... 1000. IMHO this is sufficient to cover most use cases.
If not, please reopen.

https://github.com/mixxxdj/mixxx/pull/777

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/5971