Quote Originally Posted by ArtNJ
My surround speakers had incredibly wimpy volume until I gave them a +6 decibel adjustment. They are 30 feet away from the receiver, wired with basic monster cable. Is this normal signal loss over that distance or something else?
That would depend on how far the speakers are from the LISTENING POSITION, since you naturally have diminished volume as the sound waves travel a longer distance. If your main speakers are a lot closer to you than the surrounds, then the surrounds will inevitably sound comparatively softer. Room acoustics also influence the surround levels. If the mains are positioned close to the walls, while the surrounds are in more open space, then the mains will likely generate a higher level than the surrounds because of the greater proportion of reflected sound.

Another factor at play would be the efficiency of the speakers. If you're using different speakers for the main and surround channels, then their efficiency levels won't necessarily be the same.

The room acoustics and distances are much likelier factors in what you observed than anything having to do with the signal or cabling. Even a 30 foot distance won't be long enough distance to give you significant electrical signal loss.

If you really want to do the channel balances right, go to Radio Shack and grab an analog SPL meter. Then use the tone generator in your receiver to correctly even out the levels between all of the channels. You can get the accuracy even higher if you use a test disc such as the Sound & Vision Home Theater Setup DVD.