Using Scaler Live with Mainstage as one man band

I’m Nelson, from Portugal.
I’m a user of Apple’s Mainstage and I play as a one man band, with a Boss RC-300 loop station.
After some online research, I realized that Scaler could be an interesting tool for me.
As a solo musician, I often needed a tool that would allow me, while making a chord on the guitar (which I use connected to an audio interface and use it as a real guitar and as a midi instrument, with Jam Origin Guitar Midi) to make the base/root of the bass.
In other words, as I change the chords on the guitar, this tool would give me in real time the root of the chord in a virtual bass sound of my choice from the DAW.
My question is: Can Scaler do this?

Thank You.

Hi @regidor

Welcome to the forum.

I will probably be sent to a locked room (listening to The Birdie Song on a continuous loop) for suggesting this, but I am not sure that Scaler is the right tool for your requirement.

With Scaler you can detect your input in real time so it will identify the chords you are playing. But I don’t think it can then detect the bass from your chords and output the bass note, as you play the chords in real time.

I would suggest that you could consider ChordPotion which will detect our chords and output the lowest note from each chord. Note, however it will not detect the root of an inversion, only the lowest note. So if you play the 1st inversion of F it will output A. You can route the output to any virtual synth in your DAW,

And if you want a bass motif as you play each chord you can easily program this into ChordPotion.

Scaler does work with audio and midi. If I want the bass note I assign a monophonic instrument which prefers lowest note. Or of course I just delete all the chords other than the root note. Scaler can detect audio and midi which it sounds like you are and you can assign a bass preset but that is a defined series of notes. It’s a free trial you can download and try. Chord Potion may do the translation but I don’t think it can detect audio or midi but it can translate the chords into a bass note seemingly according to @ed66 advice. Cue the Birdie song on continuous loop!

@davide I didn’t think that Scaler would output a midi signal whilst detecting an audio input in real time (i.e. act as an audio to midi converter). My apologies and I will now cue up The Birdie Song.

Thank you very much for the feedback, do you know if there is a video or explanation of how I can do it?

If Scaler doesn’t fulfil your needs you could try the free Meldaproduction MTuner. There is a video on YouTube about using it to convert audio to midi.

I use it in Reaper to convert audio samples to midi to drive a VST, but I don’t play live music.

I fear I am probably destined to join you in Birdie purgatory, but a couple of thoughts follow …

Firstly, @regidor is using Jam Origin so any chords he has are converted to midi by that. So if they are routed to a synth he can split the midi signal and use that for some process to extract a possible base line.

A fundamental issue is the concept ‘lowest note of a chord’ implies that at the point of attempting to derive that all the notes of the chord are known. However, midi is a serial process, so the notes come in a stream. Maybe close together, but if the notes are NOT in ascending sequence, the detection / selection process has to pause for sufficient length of time to have received all the notes - and that means the inbound notes have to be stored for that window of time so that the comparison of pitches can be made. That window has to be long enough to accept the whole chord, but not so long as to get confused by the next chord.
So it seems to me that although the idea of ‘lowest note’ seems very straight forward in concept, but because of the logic required to compute it, it has to be done in some ‘programmed’ environment. It requires code.

But… @regidor using a guitar, so If he only plays downstrokes, however, the first note is (by definition) the lowest note of whatever is coming (and the reverse for an upstroke). Also, by virtue of the instrument, he can only get one note from one string.

I don’t know mainstage, but I do use Cantabile (but not for live performance) and it has reasonably good midi filtering, note mapping and transposition rules. and one could then filter out notes only from the bottom E string up to the fourth fret, and if only ‘open string’ chords were played (always including that string) the you would get the low note.
I expect Mainstage has the same capabilities.

Would that be the root note ? In most cases not, but it would be in the chord, and therefore probably fine for the tune, unless it was was expected to acting in ‘basso continuo’ mode.


I am not familiar with Jam Origin but given that

Can I clarify what it is that you want to do with Scaler? Do you want it to play bass lines from the performance settings? Do you want to use Scaler to output midi from the performance bass lines?

If you are looking for Scaler to simply

then ChordPotion will do that for you. Scaler will also do this for its own base lines.

For either of these I suggest you could simply route the midi chords from Jam Origin to the plug-in.

Thank you all very much for your feedback, however this is all new to me, which means it is frustrating to know that it might be possible to do what I want and not understand anything about these tools! If anyone knows of a tutorial or video that they can share, which shows that it is possible to play a chord and the scaler gives the tone of the chord, I would appreciate it.

Returning to your original question if you simply want to use the bass line from Scaler if place Scaler on a track and then route the midi from Jam Origin Guitar Scaler will be triggered by your input. If you then want to play the “Scaler bass line” on another instrument rather than using Scaler included bass instruments just turn off the Scaler instruments and route the midi output from Scaler to the track with your preferred vsti.

There are lots of videos about Scaler on YouTube. The School of Synthesis videos are very good as they are produced by @davide, as is the Scaler 2 course.

On routing midi in Logic I suggest you search YouTube for videos on this subject.