Pure Acid and Cubasis 3 Issue


I’m working on a song on Cubasis 3.13. On Wed 02 Dec 2020 I opened the project and Pure Acid baseline synths sound different. I checked the version history of Pure Acid and on Tue 1 Dec 2020, there was the 1.5.0 update that adds MIDI out to Pure Acid. I was lucky to contact the developer JimAudio to ask about the issue. I sent him two audio mixdowns: one from Monday 30 Nov 2020 and another from Wed 02 Dec 2020. The project was completely unopened/unedited between those days. (I can provide audio clips via DM if requested)

Jim answered me:

“I hear that pitch is changed up 7 semitones. also, slides absent in the second file. slides mean Gate knob has changed somehow”

I sent him the preset that I am using and he confirmed that there was no problem with the stand-alone App and no issues with Cubasis 2 either. I checked on my iPad and I can confirm there are no issues on Cubasis 2 and with the stand-alone Pure Acid App. Jim also note:

"it also not remembering knob values after closing Cubasis
seems like something wrong with Cubasis 3. In Cubasis 2 everything seems to work without problems
you can try to ask here about PA with Cubasis 3:
https://forum.audiob.us/discussion/34910/pure-acid-by-jim-audio-this-is-the-best-news-ever/p51> "

On that forum, other users are experiencing the same weird behavior:

“Anyone having weird issues with Cubasis 3 with PA? It seems very unstable, while Cubasis 2 works good.
Just fired it up for the 1st time. Air 3 latest OS.
Writing midi note data to Cubasis 3 accurately from sequencer. > Baseline synth controls are all way off > but I have no idea if this is right or wrong.
Drums write midi data accurately to Cubasis too.”

I don’t know if the issue has something related to the Known Issue “CBT-317 MIDI event changes are ignored during playback.

In that case, could I know when it’s expected to release the corresponding maintenance fix?

I’m very happy using Cubase 3 on my iPad. Feels like sci-fi to be able to work in a truly full-desktop environment while on the go or resting on the sofa; it’s game-changing. Despite the different stability issues I am currently experiencing and the considerable amount of bugs listed in the forums, I appreciate the potential of Cubasis 3 and I keep in mind that’s an early version written from scratch.

I encourage you to keep doing great work! :+1:

Hi Marcal_net,

Thanks for your message.

The next Cubasis update will be released in a few weeks from now, and includes many AU related performance improvements.
If possible, please recheck the issue with the new update and let us have your updated feedback.


Hi Lars,

I have updated to 3.2. and unfortunately, the MIDI issue with Pure Acid 1.5.0 is not fixed with the update. I read the list of 45+ improvements of the 3.2 and the Known Issue “ CBT-317 MIDI event changes are ignored during playback. ” is not listed there. I hope it will be included in the next maintenance update.

Audio Engine Latency FEEDBACK

Following with 3.2 update feedback, after reading the announcement of " Multicore-rendering and improved Audio Unit performance", I’m experiencing just the opposite: in my iPad Air 3 (2019), on the same track, while the CPU usage remains low, the DSP usage raised considerably from a 40-50% to an 80% with lots of cracking when playing.

I realised the issue is directly related to the “Audio Engine Latency” option. Switching OFF “Prevents crackling” and leaving the option as “Multi-core Rendering disabled” fixes the cracking.

As always, congratulations on the improvement work you do with Cubasis; I wish you could release a maintenance update in the short-term.

Hi Lars,

I have updated to 3.2. and unfortunately, the MIDI issue with Pure Acid 1.5.0 is still present with the update. I hope it will be included in the next maintenance update.
I really enjoy the improvements of the new version. Great work!

Hi Marcal_net,

Please let us have a detailed step report, and share the issue with the app vendor too.

& stay well,