GK-3 - Electrical Mod for reverse mounting the pickup ( GK, Tripleplay, Antares

Started by Elantric, March 06, 2011, 01:18:40 PM

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Mrchevy

I have my external GK3 Hex pickup mounted in reverse ( wire on the bottom side) and set to reverse in the GR55. No problems and out of the way.
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adamlee011

#26
Since you guys seem to have messed with the guts of these some, any idea what to do about this short of calling Roland for a pickup? I installed a kit in an ibanez s premium. No easy task. I had it perfect but didn't like the angle of the regular bridge pickup so I went to straighten it all out and one of the wires came out of the gk pickup. At the pickup itself. So I opened it just enough to look inside and solder it back best I could without tearing the pickup wide open or burning the paper thin circuit board if you can call it that. Now I have all 6 magnets picking up sounds but crosstallk galore. The tuner on the vg99 shows all the strings lighting up when you hit one. Same with the sensitivity settings, though the one you're plucking meters strongest. Any idea how I can fix it?

adamlee011

fixed it. just had to clean and resolder all of the wires at the pickup which was a pita but fyi can be done if you're patient and careful. When I have the time and motivation i'll post the work i did on the ibanez s 970 in it's own thread. that was one heck of a job. especially for me since i have no experience with most of what it entailed. i photographed most of it at each stage.

Headless68

Glad you got it sorted - those wire look very close together

I just did the wire swap on the GK3 kit connector - once I figured out how to get the pins out ( the pic seems to be missing from the beginning of this thread on what that looks like) - can now use the VG8 with this guitar


adamlee011

Yea I did it too from the get go just for backward compatibility. I have a vg-88 and 99 but the 88 lately has bass duty (just compression and eq for my bass before it hits the amp really)  Always intended to mount it upside down. Doesn't really make sense to me not to. It was rather simple once you figure out how to get the first one out. It allowed me to snake into the control cavity without widening the existing hole too. No real choice but to take the harness off. Soldering the wires to the thin board in the pickup is another story. I actually (purposely) melted the plastic under the pickup where they each run into their own little hole in order to have room to work /see what I was doing. Here's a quick shot of the finished s. I'll have to get around to doing a step by step narrative /pictorial.

ConstruKction

#30
Quote from: Headless68 on September 12, 2015, 02:54:34 PM
Glad you got it sorted - those wire look very close together

I just did the wire swap on the GK3 kit connector - once I figured out how to get the pins out ( the pic seems to be missing from the beginning of this thread on what that looks like) - can now use the VG8 with this guitar

In addition to the recently acquired VG-99, I managed to find a nice Roland GR-30, so I had no choice but to conduct the modification. I used a needle to lift the plastic piece that clamps the pin. They seem quite fragile but actually they're flexible.

Done in ten minutes, and the GR-30 is outstanding when it comes to tracking. While not perfect, it doesn't complain about my low C string as much as the VG-99. Ha-haaaaa! No wonder Fripp still uses it.

Ciaron

#31
Apologies if this has been covered before...

I've just got myself a GK-3 which I'll be using with a newly acquired VG-8EX.

The 'donor' guitar is self built so I don't really have any concerns about drilling holes etc, but I'm a little concerned about the hex cable position on the upper bout of the guitar and whether or not it's going to get in the way of my playing.

Thus, my question is, is there a specific reason why the hex pickup can't be mounted in reverse? IE with the hex cord emerging from under the high E string, rather than under the low E string?

Thanks in advance.

Ciaron

admin

Modern Roland/Boss systems since 2007 include a choice in the GK Type user setting for "Reverse"  - which allows you to mount the GK-3 hex PU with the Wire emerging downward 

But older systems (VG-8, VG-88) do not have this functionality

Many modify their GK-3 by swapping the 6 string signal wires so you can use all generations of GK 13 processors

Read details above


Ciaron

Quote from: admsustainiac on October 07, 2015, 09:57:07 AM
Modern Roland/Boss systems since 2007 include a choice in the GK Type user setting for "Reverse"  - which allows you to mount the GK-3 hex PU with the Wire emerging downward 

But older systems (VG-8, VG-88) do not have this functionality

Many modify their GK-3 by swapping the 6 string signal wires so you can use all generations of GK 13 processors

Read details above

Thanks for this, very much appreciated  :)

howarddavidp

It's thread NECRO time!!! :)

I just bought a GP-10, which DOES have the reverse feature.  However, I kept my GR-33, so I needed to use this thread and the information here to reverse the wires.

Once again, the pictures and the info stands the test of time, as it is 2017 and I just reversed my GK-3 on a homemade EVH strat.  I will try and get some pictures posted.  I also bought a brand new GK-3 for my Ibanez RG920MQM, but I might consider getting the KIT since this is a nice guitar and it is worth it to me.

Thanks again to the original poster, this was super easy to do.

David

gumbo

Quote from: howarddavidp on September 24, 2017, 06:18:00 PM
It's thread NECRO time!!! :)

I just bought a GP-10, which DOES have the reverse feature.  However, I kept my GR-33, so I needed to use this thread and the information here to reverse the wires.

Once again, the pictures and the info stands the test of time, as it is 2017 and I just reversed my GK-3 on a homemade EVH strat.  I will try and get some pictures posted.  I also bought a brand new GK-3 for my Ibanez RG920MQM, but I might consider getting the KIT since this is a nice guitar and it is worth it to me.

Thanks again to the original poster, this was super easy to do.

David


PM me for details if you might also NOT want to dig a dirty big hole in the edge of your nice guitar in order to install the standard Roland 13-pin jack...   ...the drop-in pre-wired Synth-Linx Jack only needs a 5/8" (round!) hole   ;)  ...and only costs a measly 40USD + 5USD shipping all the way from sunny(!!) Australia...

Cheers,
Peter

Read slower!!!   ....I'm typing as fast as I can...

Headless68

I would totally recommend Peter (aka Gumbo's) 13 pin socket - I just installed one - MUCH less intrusive to the guitar and a lot easier to install - very high quality build ( in my opinion significantly better than OEM )

Headless :-)

MrSparkle

Sorry to bump an old thread, but I've got to do this reverse mod on one of my Parker Flys that had an internal GK2a installed (reverse-mounted) by the previous owner. GR-1 doesn't have the reverse option so I'm only able to partially enjoy the G-string (no pun intended).

I'm gonna have some new pickups and pots installed anyway, so I was thinking of just taking it to the shop instead of messing under the hood since I'm a little clumsy with electronics, but I'm trying to gauge whether the GK wire mod is simple enough for me to do without damaging something. Seems like it's just unclipping and re-attaching the wires? The catch is that section is really small and I'm hesitant getting in there.

I mean, I've changed iPhone batteries, but when it came to changing the GPS chip, let's just say I lost 10% of my touch screen's touch capabilities after the operation.  :-X

Headless68

its simple - just be careful as the GK wires are small so don't use force on them

chrish

This rewiring of the connector will solve two problems for me for my internal gk-3 install.

One is the reason stated for  better pickup mounting option

And two, by taking all the wires out of the connectors including the ground, I'll be able to slide the wires through a smaller opening.

Thanks for the ideas.

Maimroid

Hello!
I've been scouring this topic for a quick answer to getting the PU header pulled up off of the circuit board so I can begin the reversal process. I'm nervous that I might damage things If I just gently yank it.
This is what I have:

https://drive.google.com/file/d/1pI2-pHBeove3Xyecx_c_MfZumAbTUI4z/view?usp=share_link

Hope the link works.
There are 2 small holes on each side that look like release tabs but pressing them and prying the header up seems incredibly difficult.
Thank you!!


admin

Gently/slowly pry up vertically  with small flat blade screwdriver under tabs on each end of cable mounted 8 pin header

MS Power Point instructions
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https://www.lifewire.com/pps-file-2622184



gumbo

To expand on 'admin's excellent earlier answer....


"There are 2 small holes on each side that look like release tabs but pressing them and prying the header up seems incredibly difficult."

...that is because they were never intended to be pressed ...there is basically NO 'give' in the barbs that interlock with the holes in the side of the header, as they are simply raised sections that are moulded (as one) on the sides of the female connector.

To ease the release of the connector from the header (while prying upwards via the tabs on each end) place a VERY fine knife blade (automotive feeler gauge / razor blade ) down the SIDE of the header between it and the connector) and marginally move the side of the header away from the barbs on the connector.....this will reduce the hold on the barbs within the two locking holes.

Apply lifting force ONLY via the two tabs on the ends of the connector....DO NOT pull on the wires themselves.

Once the connector is released from the the header, you can then start to release the individual wires by using a FINE knife blade to GENTLY lift each locking pawl on the connector JUST FAR ENOUGH to enable you to withdraw the wire along with its female crimp connector.

Pulling these up abruptly or straining on them can cause them to break...if that happens YOU WILL HAVE TO REPLACE THE ENTIRE 8-PIN PLASTIC CONNECTOR.....it is a JST Series ZH 8-pin connector....and yes I have a ton of them here in Australia...but that's not going to help you much at the time.

Pay attention to the orientation of the crimp connector to the locking pawl as you withdraw it ....don't force anything and document which side of the crimp faces the locking pawl.

Only remove the six wires that connect to the individual poles of the pickup...these are the ones that need their order reversed.

Leave the wires for pins 7 & 8 still attached to the plastic connector as they have to remain in their original positions.

BEFORE you re-insert crimps 1 - 6, GENTLY press down the locking pawls that you previously lifted to release the crimp connectors so that the pawls can again do their job correctly and prevent each of the six pickup wires from becoming accidentally disconnected in the future.

HTH


Needless-to-say....when the modification to the female connector circuits is completed, correct and full re-plugging back into the header is essential to make things work again..loose or intermittent connections to these circuits will plague you until the job is done properly.


Ask questions if you want more information


Cheers,
Peter






Read slower!!!   ....I'm typing as fast as I can...

Headless68

looking back on this thread I did this mod in 2014 - Reading this just made my palms sweat again :-)

gumbo

Quote from: Headless68 on March 04, 2023, 03:44:27 PMlooking back on this thread I did this mod in 2014 - Reading this just made my palms sweat again :-)

Don't pet sweaty things.....   ;D
Read slower!!!   ....I'm typing as fast as I can...

Johnny2hats

Hello - I saw this thread refreshed so I thought I mite be a good place to ask.
I have the GK-2a attached to my guitar (not an internal mount job) with a GI-20 GK-MIDI Interface. I cant find the option to reverse the pickup direction nor have I found any mention of it in the manual.

as far as the midi pickup goes.. playing with the cable by the low E string is proving impossible for me.
Does the mod cable you sell (if you still have any..) work for the gk-2a external version?

I was thinking that If I found a male and female 13pin din socket I could just rewire them myself and have this 13pin midi adapter cable running inbetween my GK-2a and the gi-20 interface. seems like the most non-invaseive way to do it with an external rig.
do you offer anything like that? :)

admin

Reverse PU direction is Not supported on pre 2007 Roland/Boss GK 13 processors

That's why the DIY internal  hardware 8 pin divided pickup  header pin rewire-Sequence reversal is prefered-as described at top of this thread  nobody is selling an adapter here- its an easy DIY mod

Same procedure for GK-2A, Yamaha G1D, etc

Then you can just select normal PU direction on all GK Processors


GK-2A -OBSERVE WHITE 8 PIN HEADER

Johnny2hats

Thanks for the clarification. I just saw gumbos display picture and thought it mite be somthing that was sold..  I just cant find any explanations for how to do it for the external GK-2a.
also thanks for the photo - I havnt seen inside the gk-2a before but there is the header - looks pretty straight forward thanks

...I was thinking If i could make my own 13pin din cable - and just swap pins 1 to 6 to reverse the order. That way - my gk-2a is still original and I cant mess anything up inside the gk-2a.
I am pretty new to this however - can you think of any reason why that would not work?

http://johnp.net/projects/guitar-synth/roland-pinouts.html

gumbo

Quote from: Johnny2hats on March 12, 2023, 03:59:38 PMThanks for the clarification. I just saw gumbos display picture and thought it mite be somthing that was sold..  I just cant find any explanations for how to do it for the external GK-2a.
also thanks for the photo - I havnt seen inside the gk-2a before but there is the header - looks pretty straight forward thanks

...I was thinking If i could make my own 13pin din cable - and just swap pins 1 to 6 to reverse the order. That way - my gk-2a is still original and I cant mess anything up inside the gk-2a.
I am pretty new to this however - can you think of any reason why that would not work?

http://johnp.net/projects/guitar-synth/roland-pinouts.html

Yes, I still make Synth-Linx Jacks...nearly ten years after they were first released on this Forum...
https://www.vguitarforums.com/smf/index.php?board=181.0

...BUT...that will not help in this case.
Changing the order of the pickup signals at the 13-pin jack WON'T get you there, because there is internal (frequency-limiting) filtering of each of the six individual string signals WITHIN the electronics of the GK mainboard itself...you need to 'feed' each string circuit of the GK mainboard with the signal frequency it was designed to accept.


...what you need to do is to reverse the order of the 6 cables carrying the individual pickup signals WHERE they enter the GK pickup mainboard (on either the Internal kit OR the External kit)

The photos that are shown earlier in this thread of the 8-pin (pickup-to-mainboard) connector are relevant to BOTH Internal and External Roland hex pickup installations....WITH THE CAVEAT that the GK2A pickups used a slightly larger 8-pin multiplug (JST PH Series 2mm pitch) to achieve the connection, while the later GK3 pickups used the JST ZH Series 1.5mm pitch.

Since you are talking about modding a GK2A External pickup, that even easier because it just a matter of removing the screws that hold the two sides of the pickup housing together in order to gain access to the (larger PH Series) connector, which is even easier to manipulate as each circuit crimp is substantially larger and at 2mm centers instead of 1.5mm apart as in the later GK3 pickups.  ;) 


The way to achieve this is detailed in my post of a few days ago in this thread....if you can't understand that, or need more information, you are welcome to ask here or PM me.

HTH

Cheers,
Peter
Read slower!!!   ....I'm typing as fast as I can...