Recently I bought a Roland GP-8 guitar processor to use as an FX box for keys and other stuff. It only accepts Hi-Z instrument signal, so you’ll need a Lo-Z to Hi-Z converter (I use a Radial X-amp re-amper). Real-time editing isn’t what it should be when using the alpha dial on the Roland, so I built a real-time controller in the TB MIDI Stuff app. Roland sysex has been hard to program, in my experience, but it was really straightforward in the TB MIDI Stuff app.
The Roland GP-8 (1987) is like having 8 BOSS pedals in one rackspace. 6 Of them are analog (dynamic filter, compressor, overdrive, distortion, phaser and EQ) , the delay and chorus are digital. What strikes me the most when you compare it with guitar oriented plug-ins like NI Guitar Rig, is that the GP-8 has much more punch/attack in it’s tone and has a more dense sound. The great thing is that these boxes are really cheap (I bought mine for €50,-)! They sound absolutely great!! My experience with Roland gear from the 80-ties is that they just keep on working, built quality is very good.
For GP-8 / TB MIDI stuff users out there, here’s the template:
Here’s a short demo: