Roland GR-20 - Owners Manual

Started by Cobweb, August 13, 2015, 09:01:10 AM

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Cobweb

 :) Hi there folks, I've just joined the Forum and I'm hoping someone can help me with a problem I have with my Roland GR-20 Synth. I bought it a couple of weeks ago without the guitar pickup from Cash Converters. I thought I'd plug my Midi keyboard into it until I can afford the pickup unit, but the midi in doesn't work. I have a mate who has the same unit and he plugged his guitar into the 13pin socket and everything worked fine. He then connected the midi out to his computer and recorded a track on Cubase which was fine but he could not get any response when the midi in was used. I can only get the schematic for the GR-30 which is a lot different to the GR-20 but which has given me an idea that the opto-isolator on the midi in might have blown. Has anyone got the GR-20 schematic that I can purchase please ::)

Elantric

#1

RTM
http://www.rolandus.com/products/gr-20/

http://cdn.roland.com/assets/media/pdf/GR-20GK_OM.pdf

Edit - it appears it should work - might check the MIDI channel of the transmitting device matches the MIDI channel on the GR-20 



gumtown

I recall when I had the GR-20, there is a setting for midi to select either guitar2midi and/or midi input to the tone generator.
You need to switch the midi note input 'on' and check your keyboard is set to the same midi channel as the GR-20.
I don't think you need to rip it open.
Free "GR-55 FloorBoard" editor software from https://sourceforge.net/projects/grfloorboard/

Elantric

On GR20, to use as a MIDI Tone Module, need to enable "MIDI Local Control OFF mode ( page 30


kenact

I can vouch for the fact that the GR-20 will indeed work as a midi sound module. I've used mine with an M-Audio Keystation 88. It works fine.
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GR-55, 33, 30, 20, GI-20, RC-50, US-20, VG-99, VP-7
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Cobweb

#5
 ???Hi there again folks, the midi in on my GR-20 doesn't work. I connected it up to an oscilloscope and tested the Opto Isolator chip on the midi in. I get a signal when I press a key on my keyboard at the input of the isolator, and I get a signal on the output of the isolator when I press a key. Does anyone know which CPU on the main board receives this signal, and which pin is it? Hope you can help, I can get the schematic for all the GR synths except the GR-20, which seems to be completely different to all the others, the layout, the chips, etc.  :'(

Elantric

To use GR-20 as a MIDI Tone Module Follow the steps above to enable " local off " mode

Cobweb

Hi there Bub, it's not a user manual thing, I've done all that before I got on to this Forum. Has anyone got any electronics knowledge of where the signal ends up, which CPU, on the main board?
Regards,
Cobweb.

Elantric

#8
On GR-20,  must enable the "Local OFF Mode" - before it will respond as a MIDI sound module and make sound when you feed it MIDI Note-On Off messages to its MID Input from your MIDI controller  / DAW/ Keyboard, etc.


GR-20  enable the "Local OFF Mode"

1 )Turn off the GR-20

2 ) Hold down the System Edit Button

3 ) Power On the GR-20 , and LED Display shows "Lo" - (Local off) means you can now connect a MIDI cable to the MIDI Input on GR-20 and make music

kenact

#9
Quote from:  Cobweb
I've told you twice now Elantric, I went through the &&@" user manual and turned the local on/off, off/on, and it makes no difference. It's an electronic fault. If the signal reaches the CPU it's supposed to, then It's the CPU at fault. I don't know which CPU it goes to, that's why I want the Schematic. If you've no idea about electronics Elantric, then shut the **** up about the user manual. You pretentious gobshite.
Regards,
Cobweb.

Please refrain from cursing people out. It never helps anyone. Elantric is one of the most knowledgeable and helpful people on this forum. If your statement was misunderstood, please say so, and leave it at that.
Godin Session & Montreal FTP, LGXT, LGX SA, Redline, ACS, A12, A11, A10, A4
Danoblaster Baritone w/GK-3
Gretsch Nashville, Viking
Fender Strats
Fret King Supermatic
Larrivee DV03RE
Parker Midi Fly
Seagull, S&P 12
VOX Phantom XII
GR-55, 33, 30, 20, GI-20, RC-50, US-20, VG-99, VP-7
Sentient 6
Cyr 7

whippinpost91850

Coweb, I would appreciate it if you would stop the offensive language and settle down.

admin

#11
 
We do not have the Roland GR-20 Service Manual

Contact Roland Service.
or look elsewhere

And as a reminder we do enforce compliance with our forums rules
https://www.vguitarforums.com/smf/index.php?topic=3030.0

concordal

QuoteI've told you twice now Elantric, I went through the &&@" user manual and turned the local on/off, off/on, and it makes no difference. It's an electronic fault. If the signal reaches the CPU it's supposed to, then It's the CPU at fault. I don't know which CPU it goes to, that's why I want the Schematic. If you've no idea about electronics Elantric, then shut the **** up about the user manual. You pretentious gobshite.
Regards,
Cobweb.

Cobweb, you'd be hard pressed to find anywhere else on the web with the know-how to help you with a GR-20 problem.  Alienating the one source available to you makes no sense.  Apologizing does make sense.

gumtown

Looks like I missed the party?

Has a factory reset been tried on the GR-20?

Other GR-20 resources
http://www.facebook.com/pages/ROLAND-GR-20-Guitar-Synthesizer/122700021074051

http://www.synfo.nl/pages/servicemanuals.html#sm (but not the GR-20 - for future reference to others)
Free "GR-55 FloorBoard" editor software from https://sourceforge.net/projects/grfloorboard/

Cobweb

 :'(Sorry folks, I had three times my usual, Whisky, Carlesberg Special and Cider cocktails yesterday. Sorry Elantric. Gumtown, the first thing I do when I buy a pedal is to factory reset it, but thanks for saying that in case I didn't know. I contacted Roland as soon as I bought it but never got a reply from them. Anyways, I've had four times the above amount of alcohol today so I'm gonna bid you all goodbye, for good, thanks for tryin'. :)

GuitarBuilder

Did you try setting both units to another MIDI channel?
"There's no-one left alive, it must be a draw"  Peter Gabriel 1973

Elantric

#16
Quote from: tjparkinson on March 03, 2020, 07:52:27 PM
I saw your posts on VGuitar forums so I thought I'd give this a shot, seeing how you seem to be up on all these things.

I just purchased my 2nd GR 20 as a backup to the one I still use on gigs. I'd like to sync them so that the patches are the same and so I'll be able to use them interchangeably. If my current one went down or got lost, I'd be sunk.

In your opinion, what is the best way to go about doing that? (Making them both the same layout)

Thank you for your time.
Tim Parkinson

See GR-20 OM for Saving Patches  / Bulk (Sysex) Dump on pages 26-27

https://static.roland.com/assets/media/pdf/GR-20GK_OM.pdf


Most would use a MIDI <> USB cable to connect to a computer
https://www.vguitarforums.com/smf/index.php?topic=27110.0
Then if on Windows use a SYSEX Backup utility

MIDI-OX.

or

BOME SEND SX



if on Mac
use Snoize to back up the GR-20 MIDI Sysex 



gumtown

You should be able to 'Bulk Dump" all the sysx data from your main GR-20 unit and clone the 2nd GR-20 with it in "Bulk Receive" mode,
using just 1 midi cable from the main GR-20 "midi out" to the cloned GR-20 "midi in".

If you are going to make a backup copy on a computer, make sure you use a good quality USB-Midi device, like the Roland UM-One,
the cheap USB adapters will corrupt your data.
Good Windows PC program to save/copy/backup and send midi sysx data is a Shareware software called "Bomes SendSX"
Free "GR-55 FloorBoard" editor software from https://sourceforge.net/projects/grfloorboard/