Low frequency feedback

[saxman]

Hi to all!!!
I'm getting a feedback from my monitors (Alesis Monitor 1) when i play
midi note Bb0-Bb1-Bb2 with a bass sound.My monitors are wall mounted
on speaker holders.
Has anybody any idea how to deal with this situation?

[cmchamp]

Ok, are we dealing with a hardware routing loop, or an open microphone? If it's a microphone, probably sympathetic vibrations through the floor. In addition, most 'cardioid' microphones are less directional in the 100-250Hz range where those notes lie.

[saxman]

Well...my microphone (AKG C3000B)channel is always closed when i rehearse or recording midi but i'll check it once more for the vibrations thing.As for the hardware loop its true that a previous setting on my mixer (Yamaha 01v) was causing a problem (cross-bridged channels13-14 output in the settings area ,if you are familiar with the 01v)and i fixed it.The problem got less but not dissapeared.

[cmchamp]

Next to check: Are you using an outboard EQ? If so, or if not, are you using balanced cables throughout the signal path?