physics question #24

Willi Luke, a 18 year old male from the Internet asks on June 6, 1999,


I am currently doing research on the e-bow, a guitar effect that calls upon an infinite feedback loop to produce infinite sustain by keeping the string in constant vibration. However, I am baffled as to the internal components and devices that drive this implement. I hypothesize that it has a huge frequency which enables it to activate strings of variable widths, however, I am still puzzled as to the schematics. Coil type? magnetics?

viewed 14563 times

the answer

Barry Shell answered on June 6, 1999, A:

The following website ( explains it as an "electromagnetic design, involves holding a battery operated device that looks like a stubby, metallic check mark, in close proximity to the strings, near where you'd usually hold a pick. The electromagnetic vibration is strong enough to make the string vibrate by carefully holding the device right next to the string." Also, the manufacturers of the e-bow have their own site ( which has a lot of information on how it works, but obviously they don't give away their trade secrets. You might also try the Delphion Intellectual Property Network page ( - now available by subscription only) which provides access to the whole patent, complete with the electronic schematic.

Add to or comment on this answer using the form below.
(required if you would like a response)
Note: All submissions are moderated prior to posting.
If you found this answer useful, please consider
making a small donation to