ECN Forum Forums General Topics of the Trade General Discussion Area High end sound equip. interference.

Church high end sound equip.

Proximity of L.V. cabinet and H.V. cabinet's are in same room, 4 feet apart approx.

L.V. rack is supplied by ISO circuits, 120/208 3ph. PVC connections.

Dimming panel fed from same power panel.

In subwoofers,(32,000 watt Peaveys),a low end hum is present, but not always, the dimming panel when ltg. is 60% or lower adds to distortion in subwoofers at a midrange tone. The dimming panel doesn't seem to be the cause of the hum, yet it adds a higher tone of distortion.

The hum is not a great issue when system is used for music and so on. It is when the clergy is trying to speak that it is the most annoying.

Sound engineers, a few other elect. cont., and now in our lap. Many scenarios, testing, no major steps. Dirty power, ISO GRD, proximity, no definites, and we cannot produce the sound all the time, or find any differences in troubleshooting.