GR-20 --Couple questions, where to start?

Started by OBB, August 19, 2014, 01:47:02 PM

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OBB

Hi Guys,
   I'm new to the whole Midi guitar thing, although I have played guitar, bass & keyboards for over 30 years now. Not long ago I picked up an Ibanez RG420-GKBK & Roland GR-20. Both of them are brand new and were never used other than the finger smudges I've put on it and off the bat I have a few questions. Yes I already searched and found some of the answers that I was looking for helpful but I still could use some guidance on it.

Ok so here is where I'm at...
Plugged the whole shabang in and all seemed ok at first and then noticed no data signal from the G & High E string and also now is seriously humming/squealing (?) loud. So off to the forums, I went searching & the biggest thing I can see is cleaning pins, while I don't have the oxit stuff everyone says to use I do have regular old contact cleaner so I used that and then while holding the lock pins open plugged them in & out 10, 20, 30 times, turned it all back on and still extremely loud hum & still Dead on the D string & high E string.

I can hunt and peck through a schematic if needed but thought I would just ask someone... I hope someone here can send me in the right direction, before I wind up accidentally wrecking something inadvertently...

Elantric


OBB

#2
Quote from: Elantric on August 19, 2014, 01:52:53 PM
Read
How to prepare  and maintain your 13 pin GK cable
https://www.vguitarforums.com/smf/index.php?topic=3132.msg20110#msg20110

Hi Elantric,
    Yep, that was the first thing I read here and gave it a whirl but no joy...

I suppose maybe I should be asking is what is going to be the least pain (and/or cost) to help nail down the actual culprit is?

The cable that I purchased with the GR was still sealed in an original bag, and my Ibanez RG I bought from my neighbor, about a year ago, he originally bought for his son and he never even played it, heck I even went with him to buy it for his son in Christmas in 2001 and sat in a case untouched for 13 years other than maybe 1/2 a dozen lessons and then he lost interest. So I know where it came from since the day it was bought.

Somehow, I can't really see a need to clean anything yet, though I thought it couldn't hurt so I did, sprayed out the pins & connectors as you outlined as shown above (although I don't have the oxit stuff, I use good old CRC 5103, which am I sure if it's good enough for all of the pots in my arsenal of axes it's got to be good enough to clean a simple cable, though it changed nothing. But after cleaning them a second time, using a dental pick, I did push out the ground pin/lock (whichever you want to call it) and yes it was a bit as you say "flaky" and is better (once I find the problem I may do the #9 GND pin and metal sleve thing, if I can nail down this problem first) but still the G & Hi-E are still dead as a doornail... 

Can I simply check the cable itself for resistance or even just maybe simple continuity on each pin to see if it's the actual problem? I'd like to at least narrow down the playing field before buying a $75 second backup cable...

Thanks, Gene...

Elantric

#3
QuoteSomehow, I can't really see a need to clean anything yet, though I thought it couldn't hurt so I did, sprayed out the pins & connectors as you outlined as shown above (although I don't have the oxit stuff, I use good old CRC 5103, which am I sure if it's good enough for all of the pots in my arsenal of axes it's got to be good enough to clean a simple cable, though it changed nothing. But after cleaning them a second time, using a dental pick, I did push out the ground pin/lock (whichever you want to call it) and yes it was a bit as you say "flaky" and is better (once I find the problem I may do the #9 GND pin and metal sleve thing, if I can nail down this problem first) but still the D & Hi-E are still dead as a doornail... 



Suggest to actually read the supplied link, as it details  that  often brand new Roland GK 13 pin cables have issues that require user intervention and maintenance procedures.

How to prepare  and maintain your 13 pin GK cable
https://www.vguitarforums.com/smf/index.php?topic=3132.msg20110#msg20110

Often "new" Asian built electronics contacts, cable pins, Jacks, get coated with a very thin film of anti-corosive chemical film - to survive the boat trip on the pacific. Older gear will suffer from oxidation / corrosion just sitting in contact with the atmosphere where smog, ozone, dirt, sand, beer, sugar from spilled mixed drinks work in concert to destroy the integrity of the 14 separate electrical connections within the 13 pin cable interface.
This results in intermittent noises, crackles, Hum, string signal dropouts, weak string response, poor GTR to MIDI tracking  and a host of other anomalies.(like VG-99 / GR-55 flipping through the patches by itself, or GK-Volume jumping up and down )


To remove and breakdown this invisible film (new cables)  , or remove / clean the oxidation layer (old cables) from the Cable & Connector contacts, perform the following sequence  :

1 ) Apply a small amount of Caig De-Oxit to all 13pin connections on both ends of the cable. Dont forget the 13 pin connectors on your Guitar and your processor (VG-99,GR-55, etc)

2) At one end of the Roland GK13 pin cable, Depress the Cable lock on the 13pin male DIN plug end. 

3) While keeping the Cable lock depressed, rapidly insert and remove the 13 pin male DIN plug end at the GR-55 / VG-99 "GK IN" jack. Rapidly do this at least 10 times.

4) Swap cable ends.

5) Repeat Step #3 above.

6) Now, while keeping the Cable lock depressed, rapidly insert and remove the 13 pin male DIN plug end at the GK-3 "GK IN" jack.  Rapidly do this at least 10 times.

7) Swap cable ends.

8 ) Repeat Step #6 above.


---
The above procedure may restore your older Roland GK 13 cables, because over a period of time, the electrical connections are exposed to air and tend to develop an oxidation layer that restricts proper electron flow.

Heres a Link to Caig DeOxit - they even sell it at your local Radio Shack now.
USE SPARINGLY
http://www.radioshack.com/product/index.jsp?productId=29879646


QuoteI use good old CRC 5103
Read: Caig Deoxit vs. CRC Contact Cleaner
http://www.audiokarma.org/forums/archive/index.php/t-276344.html
CRC Contact Cleaner dries up and is gone, Deoxit leaves a residue to condition and prevent corrosion. They are really different.
QuoteCan I simply check the cable itself for resistance or even just maybe simple continuity on each pin to see if it's the actual problem?

Checking your cable with an Ohm meter is highly recommended

QuoteI'd like to at least narrow down the playing field before buying a $75 for a sacrificial backup cable...

Buy a good 13pin cable  from Best-Tronics for $44 here:

Best-Tronics BTPA Straight 13 pin cables
http://btpa.com/13-Pin-Midi/

mateomasfeo



Sorry you are having issues!  I feel for ya!

It almost has to be the cable/connections.  I had issues until finally bought a can of the DEOXIT and it does work wonders.  Do you have access to another guitar and cable?   Just to eliminate possibilities...


Dances with Sheep on SoundCLoud

https://soundcloud.com/dances-with-sheep

OBB

Hi Elantric,
   Thanks, you don't have to quote it word for word, trust me I did fully read it before even asked anything. Though I thank you for the link comparing the properties of CRC & Deoxit differences. I understand this now...

I went & checked at my 2 local radio-shucks and they no longer keep it on hand (even asked my guy at the small electronic hi-fi repair shop around the corner from me that I bring the bits beyond my skill level and he just eyebrowed me with a "whats it called?")... And for anyone that doesn't know this Radioshak is on the verge of bankruptcy and soon will be no more (google it) so.... off to amazon... $14.00 for a 3.2 Oz can of Deoxit Gold ...HOLY SCHNIKIES! Does it have actual Gold in it? IT SHOULD! Will have it Friday hopefully... Though lately Amazon prime seems to be seriously dragging their feet a little bit...

So where was I... yeah cable and what to do in the interim....
So after reading about Asian cables and the throngs of inherent problems & pitfalls a couple questions popped into the head forefront... first one was maybe someone maybe did a switch-a-roo with the cable maybe so, out came the multimeter and it is (well should be anyway) it's original Roland cable that was with the sealed GR-20 box & bags, continuity all pins tested, side by side were indeed 1 to 1 (1:1) for all 13 pins as well as the ground lock node...

Then checked resistance on all 14 points, and I would say that on a 15' cable... Ground was the only read at 000.10, the 13 individual pins all read from 000.40 ~ 000.60, should be acceptable... Yes?

Now I wait for the De-Oxit Gold....

Brent Flash


gumtown

#7
At which point dos the hum start?
cable > GR-20 only, or only when the guitar end is plugged in,
because I am thinking the pickup/cable from pickup to GK internal circuit board.
perhaps a connector half out inside the guitar?
Free "GR-55 FloorBoard" editor software from https://sourceforge.net/projects/grfloorboard/

alexmcginness

I had a cable that I got in 2007 with my first VG-99. It started to get noisy after 5 years or so and I used the DeOx on it with no joy. I went out and bought a new cable and everything got fixed! Sometimes you just cant fix whats broken, you just have to replace it.
VG-88V2, GR-50, GR-55, 4 X VG-99s,2 X FC-300,  2 X GP-10 AXON AX 100 MKII, FISHMAN TRIPLE PLAY,MIDX-10, MIDX-20, AVID 11 RACK, BEHRINGER FCB 1010, LIVID GUITAR WING, ROLAND US-20, 3 X GUYATONE TO-2. MARSHALL BLUESBREAKER, SERBIAN ELIMINATOR AMP. GR-33.

OBB

#9
Ok so finally had some time today to try and sort this...

Found out the hum was being caused by one of my now permanently retired planet waves TRS cables... That problem solved...

Tried the De-Oxit cleaner & lubricator... Followed the instructions of using it on the cord from here to the "T" ... unplugged everything, sparingly used a small amount, quick small spray in each cord end and while holding the lock tab and gave everything the quick 10 or 20 times "in & out" job at either end twice (spraying only once on each end)...

I let it sit for a few minutes, prongs pointed down on the stool & then plugged everything back in and powered everything back up... HOLY CRAP WTF DID I JUST DO!? The second it came on all there is now is an insane loud screech on the data end, so I unplugged it and it instantly went away... so I grabbed some the regular contact cleaner thinking maybe I used too much (though I seriously doubt I did) and the lubrication part of the de-oxit was maybe making contact somehow on an errant pin something.. So now it's clean as a whistle I plugged it back in again and still just an insane screeching (it's worse than fingernails on a chalkboard and extremely loud)

God I hope I didn't just fry this everything... I'm afraid to even plug the thing in now...

Any suggestions?

EDIT: The upside, maybe, is I didn't actually power the GR20, just the amps, the screech begins the second the data cable touches the receptacle or vice-versa to the GR20 (while still turned off)... Also if you put the data cable in and unplug the TRS the screech stops also but, if you simply touch any part of the TRS to the TRS jack body it begins (no matter of the data switch position in either case)

Elantric

QuoteNot long ago I picked up an Ibanez RG420-GKBK & Roland GR-20. Both of them are brand new and were never used


FWIW - Both are now well over 10 years old


Quote
Any suggestions?

Find a local Roland Service  / Repair center

http://www.rolandus.com/support/service_centers/
Roland Corporation U.S.
5100 S. Eastern Ave.
Los Angeles, CA 90040-2938
Customer Service Tel: (323) 890-3700

OBB

Which piece would you even need to take in for repair?

According to Roland's service map, their closest R/C to me (61108) is 2 hours, one way..! There's $100 in gas and if I bring in both pieces? There's a $250+ bill easy for each piece no matter what, even more-so out of warranty... if I'm going to do that I might as well go order a GR55 new...

Spent the afternoon calling every music store big & small in a 100 mile radius and not a single solitary store has a GR setup in store and on the floor! SERIOUSLY??? Heck no one even had a replacement cable or the GR's in stock to even test-drive, every one said they would gladly order me a GR for $899.99 or a cable for $79.99...

There's got to be a better course of action prior to it coming to either of those conclusions yet..

Elantric

#12
Quote
Spent the afternoon calling every music store big & small in a 100 mile radius and not a single solitary store has a GR setup in store and on the floor! SERIOUSLY??? Heck no one even had a replacement cable or the GR's in stock to even test-drive, every one said they would gladly order me a GR for $899.99 or a cable for $79.99...

Which explains the typical rarity of seeing Roland 13 pin systems in wide use.

Perform these steps in this order:

1 ) Disconnect all cables.

2 ) Start with headphones connected only to the GR-20.

3 ) Then add the power to the GR-20.

4 ) Then connect the 13 pin from your Ibanez RG.

Remember you should only be hearing synth tones in headphones and nothing else.



QuoteWhich piece would you even need to take in for repair?

all these:

* Ibanez RG420-GKBK

* Roland GR-20

* Roland 13 pin Cable

Get an Ohm meter and verify you have the correct Roland type cable that has all 13 pins wired "on to one" on both sides of the cable,

and with an Ohm meter check that the large chrome round shell connections on each DIN 13 plugs are connected at both ends ( this is the crucial "Ground" and often is the major source of the problems you are reporting.

And know that most Ebay resellers are selling incorrect 13 pin cables intended for Kenwood Car stereos.

Review the posts here:
GK-13 Reference Library
https://www.vguitarforums.com/smf/index.php?board=65.0


And see if any of these RMC Pickup repair / installation  centers are closer to you - they have staff that can test your rig 

RMC Pickup Authorized Installers
http://www.rmcpickup.com/authorized_installers.htm

and read Roland GR-20 Manual
http://media.rolandus.com/manuals/GR-20GK_OM.pdf

OBB

Well with fading hope, first this morning I called the only music shop that was already closed yesterday when I called around half of my planet yesterday, Guzzardo Music in Rockford, IL., and low & behold they had a GR55 sitting on the floor setup and now I know what the problem is...

So...It is not the Guitar or its internal factory installed setup and good to go, it worked flawlessly on all positions on the GR55. From there we swapped out cables (of which we both looked at side by side and are an exact match in build & every aspect of appearance), and tried both their cable & then my cable and both cables also played flawlessly on their GR55

We also swapped power supplies as well and everything still running flawless on the GR55

So... all that was left is to test GR20 itself... tried both cables on it and also swapped power supplies as well and lastly plugged in mine with the GK1 in it and then their showroom setup with the clip on GK3 setup and it failed miserably... both cables just squealing like a mofo pulled the TRS to check synth only, and to kill the ear piercing squeal that even freaked the tech out, every setup we tried we found once it was still dead on the G & Hi-E strings... So the conclusion is the GR20 itself is sadly, the culprit...

Bummer : ( 

So from here I guess I'll pry open the unit and just inspect connections and poke around a bit and see if anything maybe there is possibly just something obvious... like maybe a bad connector, burned cap, loose wire, errant ground wire or something... Will call Roland on Monday and see if the can even repair these older ones, I'm guessing not from the age but who knows... and will also call Guzzardo higher up tech as he may other avenues for a look see as well...

Going to grab my tools now... think I take a few photo's of the process as well just fer fun...

If anyone has ever cracked open any GR unit feel free to chime in...
Also is there any chance anyone may know where to locate a schematic for these things possibly?
(doubtful is my guess)

Elantric

#14
Sounds like a blown GR-20 - and only options are :


* "Try to return where you purchased this turkey GR-20

* Have Roland service center repair this - but know that most Roland Service centers do main PC board swaps  - and the cost is stupid high  - like $300 repair bill.

* use the GR-20 as a door stop.

QuoteAlso is there any chance anyone may know where to locate a schematic for these things possibly?
Large repository of old 1980's Roland Service notes:
http://www.synthfool.com/docs/Roland/Roland_Service_bulletins/

http://www.synthfool.com/docs/Roland/

http://www.bossarea.com/default.asp

www.elektrotanya.com

www.scribd.com

OBB

#15
Quote from: Elantric on September 06, 2014, 10:01:59 AM
* "Try to return where you purchased this turkey GR-20
Yep, already initiated the process....

Quote from: Elantric on September 06, 2014, 10:01:59 AM* Have Roland service center repair this - but know that most Roland Service centers do main PC board swaps  - and the cost is stupid high  - like $300 repair bill.
Yep, I learned this lesson on my Digitech 2120... $580 for 1/2 a dozen $2 blown caps, yeesh... Will still give Roland a call Monday to check & see if maybe replacement MOBO's are available. And if reasonable, replace it myself... If not last resort I suppose.

Quote from: Elantric on September 06, 2014, 10:01:59 AM* use the GR-20 as a door stop.
The last resort, ugh... don't need another door stop in the studio... : (

gumtown

I couldn't see if you had already tried this, but it may help, doing a factory reset..

Use the following procedure to clear the GR-20's internal memory and reload its factory settings.

Caution: All User information is lost during a Factory Reset. Be sure to first back up anything you wish to keep before proceeding.

1. Power on while holding WRITE?—"ALL" flashes in the display.

2. Release WRITE, and then press WRITE again.


Also the GR-55 power supply is 9 volt DC,
and I'm sure the GR-20 power supply should be 14 volt AC.
Free "GR-55 FloorBoard" editor software from https://sourceforge.net/projects/grfloorboard/

OBB

Yes, did the factory reset on it twice & also tried it in Bass mode a few times as well and the issue just persists through all of them... so, sadly it's just a flawed unit, end of story...

Guess maybe I'll just exercise a little patience and find another GR-20 or GR-55 if the time & price are right... Not really too worried about on board sounds though they would be nice, wanting more to just interface some of the synths I use for another avenue. I had considered a GI-10 or GI-20 but sounds like the data tracking & latency issues in the really early models leaves very little to desire... At least from what I've read about them anyway... and not to mention they are still fetching about the same price as a GR-20 and also prefer having the expression pedal as well... 

Elantric

#18
IMHO the Boss GP-10 has the fastest Roland Guitar to MIDI.

Fishman Tripleplay is faster and is "king of Guitar to MIDI systems in 2015