I have lots more from Spark that I would like to post, but it needs some sorting through, so here’s something of my own for now. This is an arpeggiated loop of a synthesized clavinet chord filtered in real-time with the cutoff frequency on the instrument, which happens to be the Korg MS2000. After looping it I ran it through some gentle amp modeling followed by two ping pong delays. One set very short and another set much slower. The short delay has a lot of feedback and almost sounds like reverb, while the long delay is creating the echo.
Appegiated Synth Clav
A variety of processing went into this segment of backwards Rhodes electric piano. I started with a chunk from a loop recorded during a recent performance. I reversed the chunk and then slightly time compressed in 
While working in the studio recently I plugged in a cable from an auxiliary send to record some bass and got some horrible feedback. So horrible that I was determined to record it. The reason I was getting the feedback was because the same send that I was using to record the bass happened to be turned up on the channel that I was using to monitor the signal. I realized this immediately, but the sound was quite interesting due to the subtle latency on the signal path caused by the digital hardware involved. Here’s a couple of layers of the feedback running through reverb. I also made adjustments to the pitch a time stretched the recording in a few places.
I recently recorded a few passages of clavinet on a piece I’ve been working on for a while. My Hohner E7 is still in disrepair, so I had to rely on a sampled version of the instrument. I processed the sampled version in a similar way to how I would have processed the real thing.