Crinkle

Ok, i have made a lot of progress in making sounds. I have made a midi keyboard that works with noteON noteOFF signals, and am now in the middle of trying to use the same system to generate sounds with a "cycle" object. However, i'm not quite sure where to go next in my patch:

To the left of the main keyboard, you can see i've found the actual frequencies of the C notes from most octaves, but i've hit a sort of mental block of converting the "NoneMidiNoteOn"/"NoneMidiNoteOff" signals into actual frequency numbers that can be fed into the "cycle~" command.

Also, i'm aware that even when this works, i'll be limited to a monophonic synthesizer. Would i need a seperate cycle command for each "voice" (playing or not) of the synth, and if i did, how would i use the noteON noteOFF signals from the midikeyboard setup on the left to start and stop the correct "voices"?

not-sure-exactly-where-to-go-next

hi crinkle. i had a quick look at your patch and a few things immediately jump out.

you're converting keys to midi notes and midi notes to frequencies using [select], when [coll] would be a much better option for storing and retrieving data. but you don't even need to do that as [mtof] converts midi notes to frequencies for you (tutorial 19).

for polyphony, have a look at the poly~ object.

hi crinkle. i had a quick look at your patch and a few things immediately jump out. 

for polyphony, have a look at the poly~ object.


The answer to this, along with pretty much every other question that you have had is in the tutorials. It might be a good time to swallow a little bit of pride and go through them. I promise you will learn a lot and the things you are trying to achieve are generally a lot easier with a little bit of knowledge.

Check out Poly~ as mentioned. Use the object 'mtof' inside of the poly~ subpatch, which provides MIDI to frequency conversion for key values (from keyboard). Frequencies can then feed cycle~ or whatever your using. Velocity can then feed another input into the poly~ to inform on/off states and it is here where you can create envelopes.

Any frequency manipulation e.g. FM, Octave selects can take place inside of the poly subpatch to provide voices with the same outcome, all can be controlled in main patch.

Thanks, I had come across the Coll object before, and was considering using it later in the patch, but i had a look at the mtof object example and theres a completely unexplained and dreadfully complex equation in it that isn't mentioned, explained or justified: "expr (440. * exp(.057762265 * ($f1 - 69.)))" What does that bit do? :s

That is the equation to convert midi note numbers into frequencies. It could also be written [expr (pow(2.,(($f1-69.)/12.)))*440.] which is a bit tidier and more accurate. Notice the 69 and 440 which respond to midi note 69 (an A) which is 440Hz. The 12 and 2 are there because in the 12 tone equal tempered scale the ration between each successive semitone is the 12th root of 2, or 1.059463... Have a look 

That is the equation to convert midi note numbers into frequencies. It could also be written [expr (pow(2.,(($f1-69.)/12.)))*440.] which is a bit tidier and more accurate. Notice the 69 and 440 which respond to midi note 69 (an A) which is 440Hz. The 12 and 2 are there because in the 12 tone equal tempered scale the ration between each successive semitone is the 12th root of 2, or 1.059463... Have a look here if you want more information.

Bloody hell! I'll take your word for it, as i dont hold a PHD in maths! I have learnt though, that to go one octave up is to double the frequency and as theres 12 keys per octave each semitone is 1/12 of the total distance, but as for understanding that, theres no chance! I can just use the mtof to convert midi key numbers into frequencies though? I don't have to put that big lump of maths in every time too do i?

Yep, max doesn't make everything complicated for you, [mtof] will do the job and [ftom] will do the reverse and spit out the midi note number of whatever frequency it receives. If I were you I'd trust the maths and just go with it! The only reason you'd want to start dissecting it was if you were interested in using some unconventional temperaments or tunings.

Edit: I've only got a maths A-level and that was a C, honest!

Ok, got my head around coll, its pretty straight forward, but i really need a decent tutorial for poly... i've gone through the inbuilt help file and also the "tutorial" page, but still have not the foggiest idea how this thing works!

Also, how can i make key/keyup register more than one keypress at a time, currently they're only outputting one number?

Yeah [poly~] can be hard to get your head around. First off I would advise you to try to recreate your patch monophonically using [poly~]. This will help you get to grips with the basics. Getting note information into your synth. Figuring out which bits go in your subpatch and which should be in the main patch. Using [thispoly~] to trigger mute and busy states (look at [adsr~] for velocity envelopes, it has a dedicated outlet for [thispoly~] which makes it a lot easier!).

Then once you've got your monophonic synth working properly you can look at adding extra voices, using the "target" and "steal" messages and the like.

I sometimes find looking at an existing patch and deconstructing it to see what does what can be helpful. If that's also the case for you I recommend Chris Muir's 

 which really helped me get to grips with creating polyphonic patches.

The [key] and [keyup] objects respond to as many keys as your hardware can allow, on my macbook that's about 5 simultaneous keypresses. Connect a [print] object and you'll be able to see what I mean. Were you expecting multiple keypresses to be output as a list? This isn't the default behaviour but I expect you could easily create this functionality if you wished.

I sometimes find looking at an existing patch and deconstructing it to see what does what can be helpful. If that's also the case for you I recommend Chris Muir's Simple FM Synth which really helped me get to grips with creating polyphonic patches.

I had a look at that example program, but its way too advanced, i dont have a clue what it's doing and couldn't make it make any noise. You don't need a midi keyboard do you? As i don't have one!

Try opening the "Simple_FM_Synth_Test.maxpat" turning the [dac~] on and hitting the [toggle] at the top. It should play some melodies automatically. You could even hook up a [kslider] to the first two inlets and play that with your mouse. Or have a look at 

 abstraction I made which allows you to use your computer keyboard as a MIDI source.

Try opening the "Simple_FM_Synth_Test.maxpat" turning the [dac~] on and hitting the [toggle] at the top. It should play some melodies automatically. You could even hook up a [kslider] to the first two inlets and play that with your mouse. Or have a look at this abstraction I made which allows you to use your computer keyboard as a MIDI source.

Ok, i have been working through a tutorial (proper tutorial - hands on) pdf my mate sent me, and came up with this:

which is well and good and works ok i guess, but its response times are REALLY sluggish, i know theres got to be a little bit of a delay... but is there anything i can do to make this more responsive?

You didn't save the contents of the [coll]s with the patcher (you can do this by checking the appropriate box in the object inspector). So instead I used the abstraction I pointed you to earlier and I didn't experience any delay. The only problem is you get clipping when more than one note is sounding at a time due to the summing. Check out MSP tutorial 21 which is all about the [poly~] object (notice the ~tilde~ it is different from the max [poly] object). If you use this you won't have to use 5 instances of [p voice] in your patch.

thereishopeforus@hotmail.com wrote on Thu, 23 July 2009 20:47

The only reason you'd want to start dissecting it was if you were interested in using some unconventional temperaments or tunings.

or an unconventional midicontroller which can play key number 48.6501

thereishopeforus@hotmail.com wrote on Thu, 23 July 2009 20:47The only reason you'd want to start dissecting it was if you were interested in using some unconventional temperaments or tunings.

or an unconventional midicontroller which can play key number 48.6501


Well you could still use [mtof] for that and it would work just fine! =)

Ok, i have been working through a tutorial (proper tutorial - hands on) pdf my mate sent me

I'm just curious what's not proper about the included Max/MSP tutorials? You could print them out and they'd be hands on too. :) Just to be clear, I'm not talking about the help files but rather the tutorials - the help files assume a certain level of familiarity with Max while the tutorials start from scratch and with a little patience are a superb resource.

Timing issues could come from how the scheduler and DSP settings are tweaked. However, qwerty keyboards aren't designed with sample accurate music triggering in mind. Also, they use a multiplexed switch matrix so certain combinations of simultaneously pressed keys can't work.

Crinkle wrote on Thu, 23 July 2009 17:03Ok, i have been working through a tutorial (proper tutorial - hands on) pdf my mate sent me

I'm just curious what's not proper about the included Max/MSP tutorials?  You could print them out and they'd be hands on too.  :)  Just to be clear, I'm not talking about the help files but rather the tutorials - the help files assume a certain level of familiarity with Max while the tutorials start from scratch and with a little patience are a superb resource.

Quote:which is well and good and works ok i guess, but its response times are REALLY sluggish, i know theres got to be a little bit of a delay... but is there anything i can do to make this more responsive?

Timing issues could come from how the scheduler and DSP settings are tweaked.  However, qwerty keyboards aren't designed with sample accurate music triggering in mind.  Also, they use a multiplexed switch matrix so certain combinations of simultaneously pressed keys can't work.


Not sure exactly where to go next