Midi sound generating apps, IAA, AUDIOBUS, and MTS

Discuss working with MultitrackStudio for iPad
Post Reply
Drdrdaddeo
Posts: 68
Joined: Thu Feb 09, 2017 9:02 pm

Midi sound generating apps, IAA, AUDIOBUS, and MTS

Post by Drdrdaddeo »

I have both Sample Tank and Korg Module Apps in my iPad Pro and want to use them to do MIDI Recording in MTS. They both appear in MTS under IAA Instrument Apps, and Sample Tank readily CLICKs open and plays perfectly in MTS. Korg Module similarly opens with just a click, but it does not respond to any MIDI track information (and the App has no MIDI INPUT options other than bluetooth). Assigning either Apps as an INPUT in Audiobus with MTS as the output, allows either SAMPLE TANK or KORG MODULE to appear as Virtual MIDI Apps in MTS. Either can be clicked and will appear and open as either vSAM or vMOD. Both will now receive MIDI track information and generate sound on track playback....but both are now completely detuned with regard to the original pitch and thus the pitch of all the other tracts....and not by simple semi-tone or two, but badly detuned and thus useless for playback. This detuning seems to be a feature unique to audiobus, as it does not happen in IAA (at least with Sample Tank (of course Korg Module does not receive any MIDI Data at all from MTS as a listed IAA Instrument App). Could I get some advice on how to use these resident sound generating Apps more easily?

Thanks,
Ken Hardy/drdrdaddeo
Drdrdaddeo
Posts: 68
Joined: Thu Feb 09, 2017 9:02 pm

Re: Midi sound generating apps, IAA, AUDIOBUS, and MTS

Post by Drdrdaddeo »

I did get some feedback from AudioBus support. Apparently KORG MODULE purposely does NOT support IAA mode (possibly because the KORG GADGET App is available for purchase and it is programmed to work seamlessly with MODULE in iOS without the need for IAA). Furthermore, AudioBus 2 does not support MIDI at all, but rather only Audio (but the latest version, AudioBus 3 does). The fact that both MODULE and SAMPLE TANK are detected as Virtual MIDI INSTRUMENTS in MTS at all (when inputted via AudioBus 2) is a complete mystery to AudioBus support. They also had no explanation as to the pitch detuning which occurs when playing back MTS MIDI track information through MTS's VIRTUAL MIDI INSTRUMENT option (as enable via AudioBus 2). They presumed that was somehow a feature of the MIDI management software of MTS for iPad. Hopefully Giel can shed some light on this mystery, and/or whether use of AudioBus 3 might facilitate better VIRTUAL MIDI INSTRUMENT operation in MTS for iPad (i.e. without the current abnormalities in playback pitch). Mr. Bremmers?
Support
Posts: 1717
Joined: Fri Aug 27, 2004 2:17 pm

Re: Midi sound generating apps, IAA, AUDIOBUS, and MTS

Post by Support »

The only way to detune MIDI is sending pitchbend messages, so I think it's an audio problem.

What samplerate do you use? You can see this in MTS via Song -> Properties. If it's 48 kHz you could try using 44.1 kHz. The internet seems to suggests the Korg apps work at 44.1 kHz only. This would lead to a 147 cents pitch shift (ie. 1.5 semitone).

Alternatively you could try to work around the problem using the MIDI track's pitch controller editor.

MTS does no support MIDI via Audiobus 3.


Giel Bremmers
Drdrdaddeo
Posts: 68
Joined: Thu Feb 09, 2017 9:02 pm

Re: Midi sound generating apps, IAA, AUDIOBUS, and MTS

Post by Drdrdaddeo »

PROBLEM SOLVED!! As usual Giel Bremmers was DEAD ON TARGET when he suggested changing the sample rate from 48khz to 44.1 khz. My song template was set up to automatically default to the 48khz sample rate (which I naively thought would produce the highest quality sound. Per his suggestion, I set the new song default sample rate to 44.1 HZ, opened a new song and imported my earlier multitrack MIDI data into MTS via pasting from AudioShare's PASTEBOARD. As before, the song played perfectly in tune and in sync, using MTS's General Midi Instruments as sound generators. After assigning MTS as AudioBus 2 OUTPUT and KORG MODULE as AudioBus 2 Input, "Module" again appeared as a choice in Virtual MIDI Instrument. Clicking MODULE again assigned vMOD as the instrument sound generator, allowing any instrument in Korg Module to be chosen for any track....only this time, playback was in perfect pitch and fully synced to the rest of the song!!! To my delight, the same occurred with Sample Tank which now also plays back perfectly when the default sampling rate is 44.1 Hz (suggesting that it too is designed to work correctly only at the 44.1 sampling rate). Hooray! The almost limitless variety of inexpensive instruments, their high quality, and their full functionality in both Module and Sample Tank now opens a nearly limitless palette of sound for multitrack recording in MTS.

Importantly, I got NO RESPONSE (as usual) from Korg support, only vague guidance from AudioBus support.....and not only the full explanation, but the absolute solution from MTS's genius developer, Mr. Giel Bremmers. This is why I love MTS for iPad and wouldn't consider any other iOS music recording App. Thank you again, Giel!!

Ken Hardy/Drdrdaddeo
Post Reply