[quote name='Grambo' post='737578' date='Feb 6 2010, 08:11 PM']There seems to be a lot of talk about what equipment "gives" feedback. IMHO you have to start with the instrument's individual characteristics, the dynamics of the pickup system being used and THEN worry about the amp - at the end of the day it will only be able to process the signal fed to it. I have always been able to obtain a satisfactory sound by using a good graphic eq - and I wouldn't dream of amplifying my basses without one!
For sure, some amps are better, tonally, for DB - but I think what you shove into them is important too![/quote]
I completely disagree with this. I didn't change anything except my cab when I started to experience feedback. That particular piece of equipment emphasises a frequency that causes feedback with my upright. It's not a complaint about the cab - just a characteristic.
We've probably all played gigs on electric or upright where a certain note or frequency seems to boom out. Some kind of natural resonating frequency of a room, a stage, a pa, or an amp. String instruments themselves often have wolfnotes.
Good instrument doesn't equal good amplified tone! Equally a good amp can flatter a poor instrument.
Oh dear - I seem to be going on - and confusing the issue - sorry!