I own two Guild guitars - a GAD-JF48 and D50 (Tacoma). The sound hole for both is approximately 3-13/16" diameter. This dimension is a bit smaller than a standard "black rubber" feedback buster and I've been trying to figure how to address the problem at low cost (meaning I don't want to shell out $55+ for a Lute Hole feedback buster). My solution is probably not new but I haven't heard or read about it, which is:
1. Cut a 3-3/4" disk from 1/4" thick plywood.
2. Glue a CD to the disk.
3. Glue rubber/foam pads along the edge of the plywood disk.
This link provides pictures of how-I-dunnit.
[url="http://s484.photobucket.com/...84.photobucket.com/albums/rr20 ... ackBuster/[/url]
The result is arguably very ugly or lovely but it definitely works for controlling feedback. The CD lies flat on the top and because it is thin it does not intrude with playing the guitar. Plus the "buster" fits into a CD jewel case to protect it when not in use.
1. Cut a 3-3/4" disk from 1/4" thick plywood.
2. Glue a CD to the disk.
3. Glue rubber/foam pads along the edge of the plywood disk.
This link provides pictures of how-I-dunnit.
[url="http://s484.photobucket.com/...84.photobucket.com/albums/rr20 ... ackBuster/[/url]
The result is arguably very ugly or lovely but it definitely works for controlling feedback. The CD lies flat on the top and because it is thin it does not intrude with playing the guitar. Plus the "buster" fits into a CD jewel case to protect it when not in use.