The MIDI Synthesizer Guitar I am Building

So, I got a bunch of equipment in the other day. A nice guy I know wanted to offload some stuff and I am fixing his Novation Nova Synthesizer for him. I am in discussions with Novation right now to get the data I need from them, just waiting on the NDA to show up so I can get started.

He gave me (you heard that right, all free) a Roland GR-50 rack mount guitar synthesizer and its GK-2 divided pickup (which I have mounted on my RG Ibanez for now). A cheap Robson Strat, which was missing the center single coil. So I moved the bridge to the center and put a hot Tele bridge pickup at the bridge, what a sound, it is so expressive, an Epiphone Les Paul and a Novation ReMOTE 61SL MK1. Everything works 😉

So as I have said before, I build guitars as a hobby. However, I am designing and building a MIDI guitar system, writing the software, etc. Hopefully, I'll be able to scale it down so anyone that wants one, can get one for their guitar.

This is a seven processor unit with one ARM M4 Cortex processor per string, I am just going to do some timing experiments to see if Nyquist, FFT or zero cross is the fastest in determining frequency. One of the biggest hurdles of course is layout, parts that will be used, right guitar to use, etc. I am in the process of routing out the Les Paul body right now. I have to go pick up some wood clamps later today to get the back routing done clean and straight. I did the front with my CNC, not perfect, but I will probably fix all the dings and bangs, my CNC error (overshoot) and repaint the body.

Of course of paramount concern in this little project is LATENCY. There's no point in going through all this if I can't make an uber fast system. One where even a super fast guitarist won't notice any time delays between picking strings and hearing the sounds. I hear it in the Roland and I'm not that fast when it comes to playing.

So to give everyone an idea of what all this stuff looks like, the original guitar and keyboard pics followed by my alterations and laying things out. It should be pretty neat when it's all done, 1500+ synth voices (730 Yamaha XG), 59 onboard effects, an infinite number of loadable additional voices in up to 4gb blocks via ethernet, wifi, bluetooth or an SD card, I may add a v3397 actual synth, 5 pin midi output, active or passive pickups, ARM A8 control surface with LCD and touchscreen, there is also a direct interface to USB host and client plus a 24bit/96khz output.

I am also using a pair of AD828 preamps to make the pickups active (or passive) and pass that active signal through the input block of the Yamaha XG Synthesizer module to utilize the effects in "native analog" mode where I am just using the pickups. 😉 One interesting note is that I can also do wavetable synthesis through the A8 Cortex controller, which basically means I can make/mimic ANY instrument just by sampling its output.

Novation ReMOTE 61SL MK1 with Akai APCKey 25 under the monitor.

Guitars and Cadillacs, The original messed up Robson with the Roland GK-2 on it and the Les Paul in background. Both on top of a GR-50 guitar synthesizer.

Epiphone Les Paul 100 missing the bridge pickup, which is where the divided pickup will go.

Cheap Robson Strat, but I replaced the Bridge pickup with an uber-hot Tele Bridge pickup and now it sounds like a real guitar. You can see the Tele Bridge pickup is a bit fatter than the center and neck single coil pickups.

The Les Paul after the first hole cut and routing for the ARM Cortex A8 Computer and LCD Display/Touchscreen.

Front of Les Paul showing the LCD/Touchscreen sitting on top of its hole. (it fits)

The Les Paul back and what I still have to route out

The back electronics layout, left - 6 preamps, middle top - Yamaha XG synth board, middle bottom - ARM A8 Computer, right 2 +3.3v buck converters, 2 boost power converters for the +/-12v systems, 6 processor boards and 2 batteries (forgot to place down the +5v buck converter and the AD828 preamps).

The Divided Pickup I am using, about 9k on the upper single coil and 900ohms on the 6 individual string coils.

Anyway, I have my clamps now, just went out and got them. So I may do all the back routing tonight.

Cheers - Dave

a reply to: bobs_uruncle
That's awesome! Looks like a big project and would love to hear what that sounds like.
I play electric bass and have a 6 string electric guitar I got for free. The electric guitar is a walmart special that sat in a basement for God knows how long, I'm fixing it up just have to ground it yet so it doesn't hum or send me flying across the room. I wish you the best of luck with your project!

a reply to: bobs_uruncle

Ummm... Damn!!!
Will we be hearing some Jan Hammer?
youtu.be...

youtu.be...


Sweet!!!

originally posted by: ditchweed
a reply to: bobs_uruncle
That's awesome! Looks like a big project and would love to hear what that sounds like.
I play electric bass and have a 6 string electric guitar I got for free. The electric guitar is a walmart special that sat in a basement for God knows how long, I'm fixing it up just have to ground it yet so it doesn't hum or send me flying across the room. I wish you the best of luck with your project!

Thanks ;-) I think the guy told me the Robson Strat was a cheapy Walmart guitar. I grounded everything in it, did the copper grounding sheeting as well, but man, moving the original bridge to center and sticking in a hot Telecaster Bridge pickup was just amazing. It changed everything. Now it sounds like a real guitar, not some cheezy toy. And it doesn't matter if I run through my Cube 60, Stage 100 Fender or my Behringer PA system, it comes out damned good. I am going to have to see what happens when I throw a Zoom pedal or Danelectro Distortion onto it lol.

But this guitar is my next evolutionary step. The one I did a couple of years ago had a built in Piezo, Oripure pickups I made active, a 100 effect DSP, all kinds of toys.






I'm retired so I have had a bit of time to play with things ;-)

Cheers - Dave

a reply to: Bigburgh

I have no plans on programming an arpeggiator or sequencer, but hey, it could happen if I get bored ;-) At least I am not making weapons anymore, even if it was kinda fun for a time and a means to an end making money, but I love music lol

Cheers - Dave

That is really cool. I bet you could make some wild stomp boxes also, like what was on the scene in the 60's. Wish I still had mine. Can you believe they were less then 10 bucks at the time.

a reply to: musicismagic

Yep, Pedals were $6.99 sometimes less, a full blown concert with the beatles or stones was like $5 and gas was 27.9 cents a gallon. Showing my age lol.

Cheers - Dave

a reply to: bobs_uruncle

Hahaha...

Thank you👍🏼😆



Edit: I'm just dying to hear this.🤗
🤣

a reply to: bobs_uruncle

A world of fun stuff!!

originally posted by: bobs_uruncle
a reply to: musicismagic

Yep, Pedals were $6.99 sometimes less, a full blown concert with the beatles or stones was like $5 and gas was 27.9 cents a gallon. Showing my age lol.

Cheers - Dave

I can tell we are about the same age, but gas was 23 cents a gallon when I got my first car at 16 years of age.

a reply to: Bigburgh

Only starring because of St. Cliff.

a reply to: bobs_uruncle

I have played a few, and have slaved my keys rack, synths, DX7, Yamaha Grand midi'd in and out-thru OMNI ON (I know you know) Channel 1. A midi interface...there are many....and I play my Ibanez HP or Strat thru them all.

I have a 15' x 15' stage with Keys, Marshals, guitars, pedalboards, rack mounts, pwr conds, snakes...the works.

May I turn you on to something? There are C9 Pedals and a few other Electroharmonix that simulate strings, orchestra...and the other guitar pedal is an Organ-Hammond B3 Pedal.

Early synthesis...but still on market. Play guitar, sound like a B3. Pretty cool. Good luck to you!

originally posted by: JinMI
a reply to: Bigburgh

Only starring because of St. Cliff.

Much respect. 🙏

a reply to: bobs_uruncle

Wow that’s really cool! I’ve always wanted a Roland guitar synthesizer set up. I’ve played a couple of them and got some great tones out of them. There was some latency but not that bad and easily worked around. Post some sounds when you gett’r done.

originally posted by: mysterioustranger
a reply to: bobs_uruncle



May I turn you on to something? There are C9 Pedals and a few other Electroharmonix that simulate strings, orchestra...and the other guitar pedal is an Organ-Hammond B3 Pedal.

Early synthesis...but still on market. Play guitar, sound like a B3. Pretty cool. Good luck to you!

I have the EHX C9 pedal it’s got some great sounds. I get a killer Deep Purple sound thru it AKA Jon Lord.

a reply to: bobs_uruncle

Sweet project Davie.

Since you are building a Frankenstein guitar : will you later post a sample of you jamming that famous riff by Edgar Winter, of the same name ?

( If it was a Strat body : would have called it Frankenstrat, ... oh well. Maybe next time. )

How many guitarists does it take to change a lightbulb ?

One hundred.


One to change it, and 99 to stand around and say : " I could do that ! " .. LoL !!


How many bass players does it take to change a lightbulb ?

Only one, ...

but the guitarist has to tell him what to do ... Heech-heech-heech !!

a reply to: mtnshredder

Can you believe I carried a real B3 and Leslie in the 1960's? Rent a trailer, couple roadies! Those were the days....keep up w me. I'll follow you. PS I'll bet you know of me n my group!...good luck...OMNI ON!🤺

a reply to: bobs_uruncle

Holy shiat bob !

I would never ever dare to even attempt that with my ibanez xD, i would also not succeed if i did xD
but that is amazing i am impressed to say the least

a reply to: mtnshredder

I will, like I said I might add a CEM3396 or V3397 type synth on a chip plus an LFO on top of the XG Synth. I could use maybe a TI SN76477 as well. Not sure which way I will go just yet. I did find out today though I am not great at doing routing lol. I got 'er done, just not as clean as I'd like. Added some extra power supplies to keep temperatures down and added in the pre and post pickup amplifiers.



I just hope I didn't take out too much "meat."

Cheers - Dave

originally posted by: bobs_uruncle
a reply to: mtnshredder

I will, like I said I might add a CEM3396 or V3397 type synth on a chip plus an LFO on top of the XG Synth. I could use maybe a TI SN76477 as well. Not sure which way I will go just yet. I did find out today though I am not great at doing routing lol. I got 'er done, just not as clean as I'd like. Added some extra power supplies to keep temperatures down and added in the pre and post pickup amplifiers.

I just hope I didn't take out too much "meat."

Cheers - Dave

That's insane, I like.