hans,
is this the specs of your amp?
Specifications DSP-E1000
Minimum. RMS Output Power (8 Ohms, 20-20,000 Hz)
Front Channel Does not provide main channel
Centre Channel 80 W (0.015% THD)
Effect Channel 25 W + 4 W (rear/front) (0.05%)
Pre Out Terminals Main, Centre and Effect Channels
Subwoofer Outputs
Duel Centre Speaker Capability
Remote Controllable Master Volume Motor-Driven with LED
Direct DSP Programme Access
Dynamic Power/Ch (8/6/4/2 ohms)
Damping Factor (8 ohms 20-20,000 Hz)
Frequency Response (20-20,000 Hz) +/-1.0 dB (pre out)
THD (8 ohms, 20-20,000 Hz) 0.005% (centre, pre out)
Signal-to-Noise Ratio (CD) 96 dB (tape monitor)
Dimensions (W x H x D) 435 x 131 x 386 mm
Weight 12 kg
Wouldn't it be the reason that you get a louder center channel than the mains since it is mentioned in the specs that that it is a 80Wx1 (center) and 25wX4 (effects) amp? I remember during Yamaha's AVR "pro-logic" days that they use have a 2 FRONT EFFECTS channel and 2 REAR EFFECTS channel, like for the 795 model ata. Does this mean you may need a 80x2 W MAIN channel.
Just curious.