Enter the Roland FS-7 Dual Footswitch (http://my.roland.com/products/fs-7/) or rather two of them. I can set these such that when the bypass on the GX-700 units are OFF, the green “B” light on the FS-7 is ON – i.e. a light on either footswitch means guitar or synth will sound (or both!). No more embarrassing “I haven’t turned the synth off” or “the guitar isn’t on” moments!
Deep joy! By using a stereo jack cable running from the Control 1/2 Jack output on the back of each GX-700, I can use the “A” switch on the FS-7s to send additional controls signals to each of the GX-700s (such as Harmoniser On/Off or Delay On/Off).
Have I achieved Nirvana? Sadly not. In a word, sostenuto (https://en.wikipedia.org/wiki/Sostenuto).
To make keyboard voices from a guitar sound authentic, one needs to be able to replicate the piano sustain pedal. This effect (entitled Sostenuto within the GR-50 manual) can be assigned to the Control pedal on the Roland FC-100/FC-200 using the RRC protocol, but when the GR-50 is being controlled via Midi, it can only be assigned to one or other of the S1 or S2 switches on the GK-3 pickup.
Unfortunately, guitar playing usually involves two hands leaving one with a member short to press S1 or S2 between chord changes! A footswitch/pedal is the only answer.
There’s a mod on the Internet at: http://www.marksmart.net/gearhack/gr50/gr50mod.htmlThis splices a module into the 13-pin cable to which a foot controller can be connected. All looks a bit Heath Robinson to me, surely there must be a better solution…
(P. S. These posts describe the morphing over time of the my guitar-synth setup – keep reading through to the current evolution)