TEENSY - My first own pitch to midi converter with a Teensy 3.1!

Started by PD FX, February 10, 2015, 02:43:17 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

PD FX

I'm rather glad today, since I've got my Teensy running as a hex pitch to midi converter. It is still work in progress, but the performance is allready great. I dont know if it will turn into a commercial product, it's designed to fullfill my personal needs, dont knwo if other people would like it. The future will learn.


gumtown

Free "GR-55 FloorBoard" editor software from https://sourceforge.net/projects/grfloorboard/

Albert

awesome. I've been thinking about something similar. Would you please share how you did this?


Macciza

Nice, have been meaning to get the latest teensy for a while ...
There are also some other interesting platforms, parrallax, udoo, etc
Would similarly be keen to offer assistance if wanted, do a bit of various dev  and Lemur stuff
Cheers
'70s Strat, Brian Moore iM, VG-8, VG-99, FC-300, VL-70m, StringPort, SoftStep, Sentient6, iMac QC i7 27".

gumbo

Well done, Paul!!

When you finally get everything you want working perfectly, I'll buy your GR-30s to put with my two..     :-*

All the best from Oz
Peter
Read slower!!!   ....I'm typing as fast as I can...

PD FX

thanks for your comments, guys...
It is not a public domain project, there is no information about how to do this, I've started building this from scratch. So please dont be mad with me for not sharing the code and stuff.
The perfromance is way beyond that of the gr30, it is the triggering that makes the difference. Simple facts as wavelength are the theoretical limtis defining the latency, but the playablity and perceptive speed depends on way more parameters. Thats we're I'm at: using old technique, but making it so good, that it becomes brand new.

mbenigni


Vade

Congratz on getting this up and running so well. May your boat come in on this one. I really liked the composition and your playing technique as well. I'm going to watch it again right now!
Drachen; Fender FTP Strat w/internal GK-3, Godin xtSA w/FTP, Boss GP-10, VoiceLive 3, Scarlett 18i8, ZBox IQ01, On-Lap 1502i, D:fine 4088, 4E Dual Axis Exp Pedal, VoiceSolo FX-150, Yamaha DXR 10, Gem. M2 Flute, Special 20 Harmonicas. Fender Deluxe Reverb Mahogany Cane.

https://soundcloud.com/vadie

PD FX

thanks vade, mbenigni!..
I'm working hard on the last routines that will make it perfect, if it is as good as I expect I will bring the idea to a good firm to co-produce it. There's nothing patented about the whole thing, so it is easy in that sense. I hope to make a nice little pedal with GK input and standard USB midi out, that will make any GK-enabled guitar rock.
I've tested soundengine performance between Logic on my older Macbook (buffer 128) vs. my GR30. Result: computer feels much faster..
So I'll probably skip the normal midi output, there will be only USB midi out, that will give a bit of performance boost, avoiding the midi baudrate as a bottleneck, especially in polyphonic moments.

Elantric

QuoteI've tested soundengine performance between Logic on my older Macbook (buffer 128) vs. my GR30. Result: computer feels much faster..
So I'll probably skip the normal midi output, there will be only USB midi out, that will give a bit of performance boost, avoiding the midi baudrate as a bottleneck, especially in polyphonic moments.

I imagine this was the same argument that explains why Tripleplay and GP-10 also lack 5 pin MIDI Outputs   

PD FX

true, Elantric..  Dr. Szalay himself did glue an old Yamaha GM-midi card for demonstration purposes to the tripleplay, but lateron decided that there arent any hardware synths usefull for guitarsynths...
But I will include a CV out! that will be monophonic, so you can e.g. hookup a Doepfer analog modular synth and have fun. :)

Quote from: Elantric on February 10, 2015, 08:25:41 AM
I imagine this was the same argument that explains why Tripleplay and GP-10 also lack 5 pin MIDI Outputs

supernicd

Really impressive!  Thanks for sharing and keep us posted!
Strat w/ GK-3, Godin LGXT
VG-99, GR-55, GP-10
---------------------------------------------------------------

Headless68


Elantric

QuoteBut I will include a CV out! that will be monophonic,

I bet if you offered Six separate CV Outputs  - one per string, you would gain far more sales today
https://www.vguitarforums.com/smf/index.php?topic=11610.0


http://pittsburghmodular.com/

PD FX

yes, also true, but it would require an extra mulitplexer and a sample and hold chip. and most people wouldn't need CV anyway, I mean, I havent got an analog synth myself either ')
I concentrate on getting the best pitch2midiconverter possible for now , the rest is a future affair. 

Quote from: Elantric on February 10, 2015, 11:22:53 AM
I bet if you offered Six separate CV Outputs  - one per string, you would gain far more sales today



whippinpost91850

Paul the demo is pretty awesome, I think you might just have something!!!!!!!!

jassy

All that clean triggering in the lower notes is impressive! And with fingers, really seems interesting.

Albert

Looking forward to the finished product. Personally I'd say ditch the single CV-out and add the (optional?) 6 CV-outs that was suggested earlier in the thread.

And perhaps add an expression- and a sustain-pedal in. With different hold modes. Or make it a stompbox: preferably small.

Basically the featureset of a Roland GI-20, but then smaller and faster (with optional CV-out)  ;)




PD FX

yes Albert, that setup is also my goal. jacks for 2 pedals and a volume pedal.

having 6 extra jackoutputs for hexcv would make it way bigger.. don't know, I'm still not convinced of the practicallity of hex cv.
but here is my solution: I could provide a highspeed feature port, that would carry midisignals at e.g. 115k baudrate or higher, than you analog freaks can add the cv yourselves.. schematics for midi to cv are easy to find, you only need to tune in to the higher baudrate.
This would cost just one connector on my board, and anything can be connected to it. that way the implementation of the CV will not lean on my shoulders, because it is not just cv: you might want velocity or trigger or whatever.. full featured you'd have at least 18 wires going to your modular synth!
So I propose a standard midi output on high speed, that will make the system expandable for any arduino/avr/pic freak.
Internally i allready work with this highspeed signal, so it is no development issue for me anyway.





Quote from: Albert on February 10, 2015, 10:32:02 PM
Looking forward to the finished product. Personally I'd say ditch the single CV-out and add the (optional?) 6 CV-outs that was suggested earlier in the thread.

And perhaps add an expression- and a sustain-pedal in. With different hold modes. Or make it a stompbox: preferably small.

Basically the featureset of a Roland GI-20, but then smaller and faster (with optional CV-out)  ;)

mbenigni

Quotea sustain-pedal in

Great idea.  Getting sustain to work properly has been a bear on most guitar-to-MIDI solutions to date.  As for an expression pedal input, the most flexible solution would be another MIDI Input that merges with whatever MIDI is generated by your pitch-to-MIDI processing.

I assume there will also be a GK-out or at least a 1/4" audio out for pass-through (of either hex or magnetic guitar pickups) to other effects/amps?

Paul, how are velocity sensitivity and pitch bend working?  Or are these even priorities for you?  You'll probably need some means (maybe just an internal set of dipswitches) to select pitch bend range.

PD FX

-haven't implemented ptichbend yet, my first goal is "piano", to get all notes immediately. To calculate the right amount of pitchbend after the first initial right pianokey is no problem.

-Merging midi a.k.a. "midi through" is a two sided sword.. because you have to track all traffic, it is difficult to get midi through working correctly with sysex midi messages.
it seems more correct to merge in the computer, by connecting an extra controller to an extra usb port.
I'm thinking of sticking to a very simple dial for 4 modes.
1) simple mode (1 midichannel)
2) multi
3) multi legato
3) multi bend
It is perhaps not a good idea to make the bendrange variabel, since you better adjust settings on 1 side, and the computersoftware should adapt to the standard bendrange commands! But I know that many softsynths just ignore these bendrange commands (including garageband synths and even Kontakt...)
But that is not my problem, I'll probably just stick to bendrange 24, to keep things consistent.
Using GTAK with Kontakt you can do that what the tripleplay host offers, with one setting ( 4 ) on the converter.

EDIT:
oh, and about the velocity, well I;ve got that running quite good: it is actually dead accurate. You can hear all the accents I'm doing with my fingers, there is no compression or cover up. Compression can be done best at the softsynth side. The output will allways be the same, it just the data how hard you play.




Quote from: mbenigni on February 11, 2015, 06:46:55 AM
Great idea.  Getting sustain to work properly has been a bear on most guitar-to-MIDI solutions to date.  As for an expression pedal input, the most flexible solution would be another MIDI Input that merges with whatever MIDI is generated by your pitch-to-MIDI processing.

I assume there will also be a GK-out or at least a 1/4" audio out for pass-through (of either hex or magnetic guitar pickups) to other effects/amps?

Paul, how are velocity sensitivity and pitch bend working?  Or are these even priorities for you?  You'll probably need some means (maybe just an internal set of dipswitches) to select pitch bend range.

CodeSmart

Fantastic  :D This is way cool!!!
Have you tried a GK guitar vs your Godin?
Good luck with the rest of the journey!
But I got more gear than I need...and I like it!

PD FX

Quote from: CodeSmart on February 11, 2015, 09:20:20 AM
Fantastic  :D This is way cool!!!
Have you tried a GK guitar vs your Godin?
Good luck with the rest of the journey!
thanks!.. I didn't add pots to adjust gain in my analog input stage, that is of later concern. the gain of my godin is somewhat higher as normal Gk though ..  As soon as I've built the first prototype (it is just a little breadboard with lots of wires and a cpu now..), I'll be able to adjust gain easy, and I can dial in my other guitars. There will no difference in performance, the firmware just listens to the tonal range it needs, so bandwidth differences are not that important.

Elantric


CodeSmart

I just have to ask you because I'm curious programmer trying to step down from corporate Visual Studio C++ work down to Microchip microcontrollers, is assembler coding required or is your C compiler fast enough for the triggering/waveform attack and immediate frequency detection?

I remember when I once did a VxD driver for 8 channel 12-bit A/D unit board interfacing with the parallel port in the early 90's reading a nibble at a time I could only achieve abt. 2KHz on 8 channels, and I had to do the ISR  in 86 assembler. I guess the PC's at that time corresponds to the cheap thumbnail chips we have today  ;D
But I got more gear than I need...and I like it!