Channel trim is very useful during setup, but I generally don't revisit it unless something has changed. Ideally, you'll want to pick up a sound meter at Radio Shack (analog meter sells for $30 or so, but at the moment they are only listing the digital meter on their site) and use that to set all of the channels to the same level. Qyv10's idea for setting the volume on the Pioneer was quite good, but will also require a sound meter. The 950's manual discusses using a meter some on page 27 (including the settings to use -- Slow and "C" weighting). By holding the meter in the listening position, tilted up more or less upright, you should first set the 950's volume to 00 and go to the channel trim for the left or right main (leaving it at 0), then adjust the volume on the Pioneer until the meter reads 75dB -- that's the position to leave the Pioneer's volume at. Then use the 950's tones and the 950's trim settings to make each other speaker read 75dB. This way, you don't have to second-guess yourself while watching movies.

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