I'm not sure if this belongs here but I suspect this is where the most knowledgeable electronics techs hang out. I did play my guitar through these monitors often (when they both worked). Fair enough? The problem exists with an Event active studio monitor that powers on but has no low frequency output. There is high frequency output from the tweeter. The monitor is a bi-amp affair with a separate channel for hi frequency and another for low. The woofer itself tests good with a DC resistance of about 8 ohms and no mechanical noise when the cone is moved manually. I assume the low frequency channel of the amplifier must be the problem. Besides a channel fuse or another obvious problem like cold solder joints, where is a good place to start troubleshooting this amp or solid state amps in general? I have a decent digital multimeter and soldering equipment but no oscilloscope, etc. Thanks in advance!