June 24th, 2025

Some time ago I stumbled across thread on VGuitarForums related to adding a 1/4" input to a GR-55 and at the time my thought was, if I have a GK pickup, why bother adding a 1/4" input to my GR-55? Recently I even purchased a used Bill Moore i8.13, so again, why bother?  

My band plays 90's grunge songs with a few odd tunings in our set list. For the most part I am able to program the detuning into the patches. However when I try to combine significant detuning with effects like chorus (a common combo with 90's grunge), the outcome is not good.

I do have many of my guitars set up with 3d printed quick release mounts for my GK pickup but even with that, I really dont want to be  yanking my relatively fragile GK pickup from one guitar to another on stage.

And then I recalled the idea of plugging any electric guitar into my GR-55. Incidentally, I have also have built some custom one off pedals including a clean boost that I thought might serve as an effective buffer...

So yesterday I spliced a 13 pin connector cable with some resistors and 1/4" plug. Plugged it in and nothing. Turns out I got confused and built a mirror image of the pinout. The connector soldering was too messy to salvage, so today I grabbed an messed up 13 pin cable from my salvage bin cut the good end down and added the resistors and a 1/4" jack This time it worked. 

So now I can plug any guitar I want into the GR-55 and take advantage of the fantastic amp modeling and effects options.

Thanks to Bill Bax for providing such excellent resources.