[sdiy] Mac users - excellent keyboard similar to IBM

[Olav Martin Kvern]

cheater cheater wrote: "They both vibrate the strings 
electromechanically. A solenoid would power them by literally knocking 
the guitar, using a purely mechanical impulse, and it wouldn't be a 
sustained excitation, it would be a one-time, though powerful, impulse."

I think you're getting hung up on the definition of "solenoid." I think 
that Brian's using it in a purely electromagnetic sense, not an 
electromechanical sense. These (on the Roland synth guitar and in the 
eBow--or the Sustainiac) are coils that drive the strings via magnetism, 
not mechanical impact.

I built a guitar robot that used "solenoid" in both senses of the 
term--solenoids with moving cores to whack the strings; solenoids with 
static cores to drive the strings. Great fun. I'll have to put it back 
together someday.

Here's an interesting instrument from Godfried-Willem Raes and the Logos 
Foundation--they use electromagnets to drive the strings and (moving 
core) solenoids to damp them (note--there's nudity in some Logos pages):

https://logosfoundation.org/instrum_gwr/aeio.html

Raes commented, somewhere, about slow actuation being a problem of 
magnetic string drivers, but I cannot find that text today.

See also this fantastic project from list member Ulfur Hansson:

https://ulfurhansson.com/Magnetic-Harp-Segulharpa

Thanks,

Olav