Originally posted by Tweak
Any ideas why the bass didnt have so much trouble? Proberby down to low frequencies not reflecting well / being absorbed etc or something along those lines i would guess...

Low frequencies actually reflect a lot easier than high frequency waves.
The reason the bass guitar doesn't have any problems with feedback is because of the long wavelength of the frequencies produced by the bass. High frequencies(very short wavelengths) cause feedback a lot easier.