MIDI Keyboard "oscillation effect"

saichaitanya88's icon

Hey i noticed that my midi keyboard has an oscillation effect which makes notes that i hit sounds kind of like a siren.. (this is true for 2 or more notes) but if i hit a single note it does not do this oscillation.

I tried it with the midi patch i have made, as well as the midi patches available through the max tutorials.

did anyone come across this? can anyone give me suggestions on how to fix it?

thanks a lot!

Holland Hopson's icon

You might be hearing an artifact produced by phasing. Can you post an example patch?

saichaitanya88's icon

I was using MSP tutorial number 18.. same issue with that. (I think that it might be phasing too.. because the effect is only noticeable when you hit the notes that are close on the scale)\

in anycase..i am uploading the patch that i was working with as well.

thanks!

Holland Hopson's icon

I think the sound is distorting due to summing full-scale signals. If you add a [*~ 0.3] after the [cycle~] object in each [patcher midi] then you'll hear amplitude modulation without crunchy distortion.

By the way, (and apologies if you already know this) there's a subtle but important difference between [patcher midi] and an abstraction [midi]. Tutorial 15 gives more detail.

saichaitanya88's icon

I'm going to do what you suggested and let you know how that goes. btw, i didnt know the difference you mentioned.. so i'll check it out.thanks

saichaitanya88's icon

hey i tried what you suggested.. unfortunately the oscillating effect remains.. I've narrowed it down to this case: when two notes are being played from the same channel the oscillation occurs.. so i believe the error is somwehere in the [patcher midi] but am unable to locate exactly where..

edit: when i meant channel i meant in the [patcher midi] you can see the signal splitting into multiple channels, if i have 2 notes from the same channel this oscillating signal comes.. other wise the signal is a stable tone (even for chords).