Hapax Definition Files How-to Guide

Hi all

Apart from the brief mention in the Hapax manual and the downloadable example files, has some good person written, or even better created a YouTube tutorial beginners guide to creating definition files? Or is it simply just a matter of copying the example files and making them specific to the instrument you want to define by using the CC numbering that the specific instrument manufacturer assigns to a particular function that you wish to control?

Thank you

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@Jimbo it is pretty much that - replace the CC’s and PC’s in any sample definition file with those relevant to your specific instrument.

I’ve created 3 so far, and the only problem I’ve had is that in the case of two of these (my Virus TI2 and BeatBuddy drum machine) I’ve had to add 1 to each PC and CC value to get the desired result. Of course that’s not unique to Hapax.


Thanks very much DovJ, it’s kind of what I expected really - a trial and error game to an extent I suppose. I feel lucky that so many others have already created files that will work with my hardware.
Scanning through the existing files on the forum, it looks like the only three I need to make are for Elektron Analog Rytm mk2, Erica-Sonic LXR-02 and the Abstrakt Avalon.
Hopefully it’ll make sense after a few attempts.

Thanks again :pray:

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I’m not that comfortable with the depths of MIDI and CC and PC programming - what was it that you needed to add 1 of each for? How exactly was that necessary, what was the desired result and how did adding something to both sections help?

I feel like this might help me too, the Bass Station II has things like “26:58” in its CC list. That goes beyond my understanding already; I thought CCs are “this control channel with that value from 0 to 127”…

This for example is the osc 1 fine spec:

The first number is the CC value and the number after the colon is the default value it starts at. So in this case its saying osc 1 fine is CC 26 and its starting at value 58 so when you turn on the hapax that would be the baseline value, if that makes any sense.

edit: so the 58 probably means the tuning is set to +0 so its in turn. If you went up to 127 you’d probably be several notes out of tune and if you went to 0 it would be several notes below, out of tune.

In the case of the filter cutoff, for example, you’d probably want the second number to be 127 which would mean its fully open and 0 would be the filter fully closed.


Hey there haslo,

Thats not quite right in this specific case.
For some parameters the BassStation 2 uses CC pairs for higher resolution control. The Osc Fine Tune controls are an example of that.
Basically this gives higher resolution control over some of the parameters making the controls 8-Bit.

In the example you gave the Osc 1 fine control is made up of a pair containing CC26 and CC58. As Hapax is either 7 or 14 bit but not 8 bit, you’ll need to just use a single CC which will be the first CC in the pair (in this case CC26)This gives a reduced resolution control although it’s still totally useable enough it just gives you 128 values to play with across the full range instead of 256.

In an instrument def file a default value for this parameter would be 64.
The Osc Fine tune is a bipolar control meaning at the 12’o clock position, no fine tuning is applied, turning clockwise will increase the fine pitch, turning counter clockwise will decrease it.
So the default value should be set as 64 which is halfway between 0-127 this will put the default value at the 12 O’clock position of the pot.

Be careful though, not all default values are for bi-polar controls, eg Filter Cutoff which is unipolar, you’d want the default to have the Cutoff fully open therefore a default value of 127 as OldmanChompski says. Some others may need a default value of 0 so that they are not engaged at all by default.

I’ll upload the Bass Station 2 Instrument def file I made which might be useful to check out.
It all sound pretty confusing at first but to be honest once you’ve practiced making a couple of instrument definition files you start to fly through it.

Hope this is helpful!


It’s very helpful indeed, makes perfect sense! Thanks! Also thanks for your instrument definition file!


Hello, would you mind sharing your instrument definition for the Virus TI2 please?

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There is one somewhere on this site, but I’m glad to share my (slightly) customized version.


Please let me know after you’ve downloaded so I can close the link.


Thanks so much! I just downloaded it :grinning:

I just tried it, but I get a syntax error on line 40, not sure why… excuse my naivety

Which Hapax OS are you running?

It could be that a recent version, which I haven’t loaded, has changed something.

i’m on the latest from the Squarp website, I can’t check right now as i’m working.

That’s probably the issue. I have not loaded 1.13.

It will be a while before I do load the latest firmware and troubleshoot this on my hardware.

i think i had that problem, i resaved it from my downloaded copy and reloaded it to hapax and all worked.

Is there a Simple Step-By-Step guide( video would be best) how to make the Hapax Instrument Definitions files available ?

I like to make file for my Korg PolySix and set up a midi channel and name.

  • The “Instrument Definitions” file is a bit to complicated for this “simple” action :slight_smile:

not everyone is a computer programer :frowning: haha

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I second this idea … :blush:


@Jimbo did you by chance create already the definition for the LXR-02 ? If yes, could you share it?

Hi - no, I sold my LXR-02 before I made a file as couldn’t work with the UI. I also sold the Hapax. The files follow a similar pattern, so all you need to do is extract the midi control number info from the manual and add it to the definition file. It’s very straight forward once you get the hang of the process.