Ableton Forum

...or I am just being thick?

Why do you think it doesn't? How would it be able to control the length of a note if it didn't?

If you map, for example,a send to a midi note generated on a track and play the note the send flicks to full on, but if you only play the last half of the note the send control does not return to zero, in fact nothing happens. I would have expected the note off at the end of the note to do return the send to zero.

To answer your question, it would be possible for a midi note to contain a on command and a duration to convey the note info, instead of a note off at the end. In fact this offers some operational advantages in terms of look ahead, but I dont know if this is ever done or indeed supported in the protocol.

I assume it just sends a Note On with velocity = 0 to indicate end of note...?

Macrostructure wrote:it would be possible for a midi note to contain a on command and a duration to convey the note info, instead of a note off at the end. In fact this offers some operational advantages in terms of look ahead, but I dont know if this is ever done or indeed supported in the protocol.

It's tricky to build a keyboard that knows in advance how long you are going to hold a note.

-Luddy

It's just how midi works, a note is held until the 0 velocity is sent.

Macrostructure wrote:If you map, for example,a send to a midi note generated on a track and play the note the send flicks to full on, but if you only play the last half of the note the send control does not return to zero, in fact nothing happens. I would have expected the note off at the end of the note to do return the send to zero.

ha you mean you'd like a momentary mode for midi mapping with notes ? Okay sorry, i don't think it's possible, i think it's only toggle, but let me check.

chapelier fou wrote:It's just how midi works, a note is held until the 0 velocity is sent.

Actually it's a bit more complicated. The midi standard provides 2 different kinds of note off messages.

1. Note on with velocity 0

2. "True" note off message with some value > 0 for release velocity

In my experience, Live usually sends "true" note off messages with velocity 64.
Maybe this leads to unexpected behavior in some situations.

broc wrote:

chapelier fou wrote:It's just how midi works, a note is held until the 0 velocity is sent.

Actually it's a bit more complicated. The midi standard provides 2 different kinds of note off messages.

1. Note on with velocity 0

2. "True" note off message with some value > 0 for release velocity

In my experience, Live usually sends "true" note off messages with velocity 64.
Maybe this leads to unexpected behavior in some situations.

Uh ! Gonna look at this. You learn everyday ! thanks

I don't think you can send a note off without first sending a note on message. When you start the clip half way through a note Live knows it has not sent the note on so it won't bother to send a note off.

<geeky>
The reason for using a note on with velocity 0 instead of a note off is because of a concept called "running status" which is designed to reduce the volume of MIDI data. The first byte of every MIDI message is called the status byte, it says which type of message it is and which channel it belongs to. If you send a lot of messages of the same type all at once (like moving a mod wheel or something) then you only need to send the status byte with the first message. Basically you only need to send a status byte when the message type is not the same as the previous message sent on the interface.

But it doesn't work very well with note data because of the tendency for note on and note off messages to alternate. By using a note on with velocity zero instead of a note off you can take advantage of running status compression.
</geeky>

broc wrote:In my experience, Live usually sends "true" note off messages with velocity 64.
Maybe this leads to unexpected behavior in some situations.

Yup...



Now... where did I see that velocity=0 signal? hmmm...

luddy wrote:

Macrostructure wrote:it would be possible for a midi note to contain a on command and a duration to convey the note info, instead of a note off at the end. In fact this offers some operational advantages in terms of look ahead, but I dont know if this is ever done or indeed supported in the protocol.

It's tricky to build a keyboard that knows in advance how long you are going to hold a note.

-Luddy

I'm not talking about keyboards, I am talking about midi note data written in Live.

Macrostructure wrote:To answer your question, it would be possible for a midi note to contain a on command and a duration to convey the note info, instead of a note off at the end.

OK, how the hell can MIDI see into the future and know when a note will end?

Not to mention there is no room in the MIDI message to hold duration information

macrostructure is correct.
it _could_ be possible for the sequencer to send a note off message when a note end is reached, regardless if there was a note on before or not.

i guess this makes a good entry for the never ending wish list...

Robert

I do notice I get a fair few stuck notes sometimes. Maybe it's to do with me running clips that have a note on at the end, then run to a New clip with a note off in (if it doesn't send offs when it doesn't think it needs to). I shall investigate next time I have the hardware synth out...