I just purchased a pair of Event TR8 powered monitors to use with my sampler/sequencer. When I first turned them on I can hear a local radio station very loud. This is with no input plugged in at all. Changing the input sensitivity on the back panel has no effect on the volume of the interference. When I hook them up to the sampler the noise is the same. Adjusting the volume on the sampler has no effect on the level of the interference. Both speakers are hooked up to the same outlet. I've tried lifting the ground - no change. Would using a balanced input have any effect on something like this? I currently only have cables to hook them up unbalanced.
I have a pretty decent vinyl setup that has no interference at all.
It sounds like the problem has to do with the electrical connection rather than the audio if you can hear the problem in both of them without any audio cable connected. If you lifted the ground with no change, I would question whether the outlet you're plugged into is truly grounded. Plug the monitors into other outlets and see if the problem ever goes away.
If the amp chassis is not properly grounded by the 3rd leg of the AC line the chassis itself could be serving as an antenna. Go to Rat Shack or a hardware store for an inexpensive tester that plugs into your outlets and checks for proper wiring. If the wiring is good and you get this with no input the fault lies in the monitors; take them back.
They may not be defective as far as the manufacturer is concerned, but that only means that his testing facility isn't within the same proximity of a radio broadcast antenna that you are. I'd return them. A well engineered amplifier should not do that.
It could be that your inputs are a problem, especially with there being both balanced and unbalanced ins. If push comes to shove and you can't return them try inserting plugs in all the input jacks, and wire them so that all the terminals are grounded; this will short all the input signals and then the amp should be dead quiet; in that case using balanced ins may fix the problem. If you still get radio with the inputs all shorted there is no cure likely.
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