Numark MixTrack Pro with Backspin! and more

[djfreije]

There are many, and important changes (Scratch) from my last mapping: viewtopic.php?f=7&t=3761
So, I open a new post and resume the list of changes:

// A lot of work. Almost all work like expected.
// Resume and Particularities:
//
// Load track: Only if the track is paused. Put the pitch in 0 at load.
//
// Delete + Hotcues: Clear Hotcues (First press Delete, then Hotcue).
// Delete + Reloop: Clear Loop.
// Delete + Manual: Set Quantize ON (for best manual loop), or OFF.
// Delete + Sync: Set Pitch to Zero.
//
// Keylock: disabled on wheel touch when in scratch mode (make noise anyway at exit scratch).
//
// Gain: The 3rd knob of the "effect" section is "Gain" (up to clip).
//
// Effect: Only Flanger. 1st and 2nd knob modify some parameters.
//
// Cue: Don't set Cue accidentaly at the end of the song (return to the lastest cue).
// LED ON when stopped. LED OFF when playing.
// LED Blink at Beat time in the ultimates 30 seconds of song.
//
// Stutter: Adjust BeatGrid in the correct place (usefull to sync well).
// LED Blink at each Beat of the grid.
//
// Sync: If the other deck is stopped, only sync tempo (not fase).
// LED Blink at Clip Gain (Peak indicator).
//
// Pitch: Up, Up; Down, Down. Pitch slide are inverted, to match with the screen (otherwise is very confusing).
// Soft-takeover to prevent sudden wide parameter changes when the on-screen control diverges from a hardware control.
// The control will have no effect until the position is close to that of the software,
// at which point it will take over and operate as usual.
//
// Auto Loop (LED ON): Active at program Start.
// "1 Bar" button: Active an Instant 4 beat Loop. Press again to exit loop.
//
// Scratch:
// In Stop mode, with Scratch OFF or ON: Scratch at touch, and Stop moving when the wheel stop moving.
// In Play mode, with Scratch OFF: Only Pitch bend.
// In Play mode, with Scratch ON: Scratch at touch and, in Backwards Stop Scratch when the wheel stop moving for 20ms -> BACKSPIN EFFECT!!!!.
// In Fordward Stop Scratch when the touch is released > Play Inmediatly (without breaks for well mix).
// Border of the wheels: Pitch Bend.
//

Enjoy it. Any idea is welcome.

* Tested OK in Mixxx 1.10 and Mixxx 1.11.0-beta1, under Ubuntu Linux 10.04 64 bits.
* Tested OK in Mixxx 1.10.1 under Windows 7 64 bits.

Edit 2012/06/27: This is my final version for Mixxx 1.10.
I working now under Mixxx 1.11 and this is my last Script, with Brake Effect: viewtopic.php?f=7&t=3849

I make a wiki. May be it help to understand something: http://www.mixxx.org/wiki/doku.php/numark_mixtrack_pro

[kenaveli]

Nice I will give both 1.10 and 1.11 a try. Thanks for the hard work! I believe this update will help out a lot, hopefully in the scratching area too. If it means anything to you, I noticed that the volume knobs on the pro for the headphones start to distort past 50%, no matter if I am using the included DAC on the Mixtrack Pro, or an external DAC with an amplifier (set w/ gain low or high, doesn't matter). Do you think it is somehow possible to adjust volume control with this script? I have all my .mp3s using replaygain tagged to 89db with +6db boost and minimal clipping on the VU. My recorded mixes sound really nice in my equalized car stereo system and when playing live at home, but my Allen and Heath Xone-XD 53s headphones are distorting when they shouldn't be. Playback of the recording in QMMP while listening with the headphones does not distort.

[djfreije]

Nice I will give both 1.10 and 1.11 a try. Thanks for the hard work! I believe this update will help out a lot, hopefully in the scratching area too. If it means anything to you, I noticed that the volume knobs on the pro for the headphones start to distort past 50%, no matter if I am using the included DAC on the Mixtrack Pro, or an external DAC with an amplifier (set w/ gain low or high, doesn't matter). Do you think it is somehow possible to adjust volume control with this script? I have all my .mp3s using replaygain tagged to 89db with +6db boost and minimal clipping on the VU. My recorded mixes sound really nice in my equalized car stereo system and when playing live at home, but my Allen and Heath Xone-XD 53s headphones are distorting when they shouldn't be. Playback of the recording in QMMP while listening with the headphones does not distort.

Hi. Sorry my English.
Before buying the Mixtrack Pro, i proved that of a friend and he tell me the opposite, that the volume of the headphones was very low. The same problem i find now in the web: http://serato.com/forum/discussion/564009
I don't have the low volume problem (at least with mixxx) and, i try now to reproduce your problem, but i don't have the distortion problem.
My Mixtrack Pro is strange because don't match with the pictures of the web. Is an European version, i think, because have the tracktor software (i buy it used so the license go off, don't work). The buttons of Hot Cues says "Eq Kill" in my Mixtrack Pro (like in the Mixtrack) but it have internal soundcard. I take some pictures right now:
https://picasaweb.google.com/lh/photo/u ... directlink
https://picasaweb.google.com/lh/photo/n ... directlink
https://picasaweb.google.com/lh/photo/F ... directlink

I suppose that maybe the amp of the headphone is different in mine. I don't know.
The headset I'm using is the cheapest i find: Numark HF125. With the headphone knob at 60% the volume sounds without any distortion and very very high, so i don't up any more the knob for my own ear safety and headset safety . Anyway, is good to have more to up with the knob, for cueing a low intro in a loud party for example.
Another thing i find, is that the Numark HF125 have an impedance of 32 ohms, and the Allen & Heath Xone:XD-53 have 36 ohms. I don't know if concerns in something of not, but maybe.

I can't prove now the RCA output 2, my family is sleeping, but tomorrow i try.

The only thing that happens to me for your problem, in the script, is to limit the volume of the knob. Knob at 100% = 50% of real volume of headphones, but i repeat, is good to have more to up with the knob, for cueing a low intro in a loud party for example.

[djfreije]

I try the headphone output through the RCA output 2 of Mixtrack Pro.
With the track gain to the top of the yellow area of mixxx vumeter (almost clipping), the sound have distortion at 75% of the headphone knob.
With the track at middle gain, track in the green area of the mixxx vumeter, the sound don't have any distortion at 100% of the headphone knob, so i think is fine.

[kenaveli]

I understand what you mean. My Mixtrack Pro has the hotcue buttons instead of the EQ kill. I wish I knew the specs for the DAC on the Mixtrack Pro. From what I have read the output impedance on the DAC cannot be larger than 1/8th of the impedance on the headphones. My external USB DAC specs show "3.5 mm headphone output for headphone impedance 16 to 200 ohms." You are right about the A&H headphones having 36 ohms. The A&H should work well and they do, just not while using Mixxx. I checked on your Numark HF125. I noticed that they are fairly inexpensive and I will buy a pair for $12 to test it out, then I will give it to one of my kids since they are always asking to use mine.

I think for testing purposes, I can just remove the Mixtrack Pro out of the equation and just use the mouse with Mixxx and adjust the volume on the Mixxx interface. This would probably tell me if it is an issue with the knob, the hardware, or even software. My whole goal is at least be able to get at least 75% on the volume knob without any distortion. To me that would be a huge improvement so I can acurrately mix. It is so hard to know if your bass is too powerful or weak when you hear nothing but distortion. I also noticed the distortion is at its worst when the "CUE MIX" knob is set in the middle of CUE and PGM. It is really not bad enough to complain about when the knob is all the way on CUE.

I am glad it is the weekend, so I can finally try out your updates to this script. Thanks again. Oh, I just noticed your post about the RCA outputs. I cannot try them out as everything is HDMI and USB, but is very good to know.

[kenaveli]

I tested out your script. Very nice work with the scratching. I still need to understand/test the rest of the changes though.

I believe I have resolved my issue with headphone distortion. I tested out both the internal DAC on the Mixtrack Pro and my external USB DAC. I found that the distortion in the headphones is caused by the Normalization boost feature in Mixxx. I ended up reducing the boost to 0. While using the included DAC on the Mixtrack pro, I am now able to get to 80% on the headphone vol knob, even when the CUE MIX is in the middle. When I tried my external DAC, it gave me 95% on the headphone vol knob.

I just realized that there are individual channel gain knobs on the Mixxx interface and used them to get the percieved loudness back to the same level. I do not know why I never noticed them before, probably because these knobs do not exist on the Mixtrack Pro and expected this feature to work with the vertical faders. I also noticed that when adjusted its stretches/shrinks the view of the waveform to fill in its window. It appears I am still learning the ins and outs of this program. I will be checking to see if I can use the keyboard to adjust these knobs as I hate using the trackpad. Anyway, I am very happy now as my recordings are sounding better than ever. I will continue testing this script. Thanks a bunch.

[djfreije]

I'm glad that you have solved the problem of the distortion.

The gain control is essential for me, to match the volume of the tracks with the two headphones cue active.
So i sacrifice one control of flanger effect and i put the gain control in the 3rd knob of the "effect" section of the Mixtrack Pro. That of the right. Is hard to explain with words. Look at the wiki, there are two knobs named "27". The "27" of the right is the Gain: http://www.mixxx.org/wiki/doku.php/numark_mixtrack_pro

If you up to much the gain, and clip, the LED of the "Sync" button turn ON to alert.

[kenaveli]

I tried the individual channel gains. The left "27" knob adjusts the left channel gain and the right "27" adjusts the right channel gain. Great job! I was able to get the SYNC light to blink when clipping, but it gets real distorted way before it starts blinking. I expected if you had replaygain enabled in Mixxx that it would not have to adjust the gains dramatically between tracks. I had to turn up the gain almost all the way on half of my tracks. I use easyMP3gain to tag the mp3 gain values and it does so in 1.5 db increments. I wonder if there is a better solution.

Another thing to note, the SYNC feature actually works now. That is awesome. In the past, I have just been using it to synchronize the BPM, now when pressing SYNC the tracks are in phase about 80% of the time versus 20%.

[djfreije]

For your comment of SYNC i think you are in Mixxx 1.11 that have better BPM detection. So, maybe the distortion that you have is only Visual distortion. Mixxx 1.11 by default have a value of 1,5 in Options/Preferences/Interface/Visual gain/Global visual gain. The first thing i do when upgrade to 1.11 was change that value by 1.

I take some screenshoots. I load two tracks and set the individual gain for the top yellow area of individual vumeters (if i up more the sync button turns on). Volume sliders at 75% and Master at 50% for yellow area of master vumeter too.

Look at the waveforms with Global visual gain at 1 (fine to me):
https://picasaweb.google.com/lh/photo/K ... directlink

Now look at the waveforms with Global visual gain at 1.5 (to much clip):
https://picasaweb.google.com/lh/photo/N ... directlink

This is the correct value for my taste:
https://picasaweb.google.com/lh/photo/3 ... directlink

Replay Gain i never touch that, is by default:
https://picasaweb.google.com/lh/photo/I ... directlink

and never tag anything related with gain in my mp3 files. Generally i move the individual gain knob once, at 60% (+/-), in the first load of Mixxx, and simply adjust a little (or not) the individual gain of each track i load.

[kenaveli]

I found out what was happening with the gain knob distortion. The "27" knobs do not have a stopping point. On the Mixxx interface the gain knob appears to have a stopping point, but does not stop at 100%. I didn't realize I was bringing it up that high. LOL . Last night I watched more carefully and did not have to adjust gains to drastic. I started off at 75% this time on the "27" knobs and only had to add +-5% most of the time. I listened to last night's recording in the car this morning and it sounds much louder and cleaner.

I am currently using Mixxx 1.10.1, but by looking at your pics of 1.11 there are significant changes. I think I will make the switch real soon.