mixxx VS audacity

Mixxx is excellent and has pretty wide hardware support.

FYI the "limited" functionality of Rekordbox can be hardware unlocked with some Pioneer controllers.

https://mixxx.org/

There are quite a few DJs that use Ableton for DJing (or hybrid sets). Of course, Ableton wasn't made with DJing as its main function in mind but you totally can use it for that purpose and (with some tweaking) do everything and more that would be possible in a dedicated DJing software (like Traktor or Rekordbox or Mixxx)

I’ve used Mixxx a little bit and have been surprised how capable it is. It’s an open source project and is free to download: https://mixxx.org/

Mixxx (this one's free)

Mixxx

Related works: https://github.com/mixxxdj/mixxx/pull/4027

Mixxx (you already mentioned this; it's certainly a great piece of free software to test the DJ waters with and works with a lot of gear).

Alternatively, you can also use Mixxx with the S4 MK2. Mixxx is free. But instead of a Traktor control vinyl record, you'd use Serato timecode instead, as stated in the docs.

If the device is class-compliant, i.e. it follows the generic USB spec and doesn’t need drivers installed, it can work under Linux. However the free software you get with the controller (Serato, Rekordbox, Traktor etc.) won’t. The alternative is to use Mixxx. It’s free and open source. You can check their controller support. https://mixxx.org/

If you don't like any of those, aren't you glad you didn't spend the money to find out the hard way? There's more DJ software than those two, so try out these as well: Traktor Pro 3, Virtual DJ, DJUCED, or Mixxx.

#5467 Fix 24-bit recording.

The time stretch algorithm is implemented in https://github.com/audacity/audacity/blob/master/libraries/l... particularly functions _time_stretch and _process_hop. It looks to me like a classic phase vocoder with vertical phase coherence (c.f. https://en.wikipedia.org/wiki/Phase_vocoder).

The basic idea is this. For a time-stretch factor of, say, 2x, the frequency spectrum of the stretched output at 2 sec should be the same as the frequency spectrum of the unstretched input at 1 sec. The naive algorithm therefore takes a short section of signal at 1s, translates it to 2s and adds it to the result. Unfortunately, this method generates all sorts of unwanted artifacts.

Imagine a pure sine wave. Now take 2 short sections of the wave from 2 random times, overlap them, and add them together. What happens? Well, it depends on the phase of each section. If the sections are out of phase, they cancel on the overlap; if in phase, they constructively interfere.

The phase vocoder is all about overlapping and adding sections together so that the phases of all the different sine waves in the sections line up. Thus, in any phase vocoder algorithm, you will see code that searches for peaks in the spectrum (see _time_stretch code). Each peak is an assumed sine wave, and corresponding peaks in adjacent frames should have their phases match.

https://github.com/audacity/audacity/releases

If you are able to build from source, you could download the latest source code, or the latest release version source code, and manually apply the patch.

FWIW: We'll be ditching the atlases for 3.4 most likely, in favor of having themes work like they do in source anyway: With individual PNGs for the icons and a Colors.txt containing all the color definitions. With that, custom themes would be much easier to author and also would stop breaking every time we introduce a new icon.

https://github.com/audacity/audacity/issues/4639 this bug mentions everything, I guess it's Audacity after all. To be fixed in 3.3.2

No there isn't. I searched in vain for a workaround, and then checked the Audacity issues and found this: https://github.com/audacity/audacity/issues/3385