My setup is Yamaha 795a amp, Kef Q35.2 fronts and a Q95.2 centre, and a fairly cheapo (can't remember the model) Yammy sub. I have set all my speakers to 'small' and my LFE setting is 'SW only'. Thing is, when I listen to music sources in particular (MTV, CDs etc) and turn 'effect off' on the amp i.e. vanilla stereo, I seem to get much better bass response from the system than when I leave it in Pro-Logic. I first put this down to my centre not being up to it, but have changed this opinion for two reasons. First, I've been advised by people I trust that the centre I have is actually have decent and should provide good balance with the rest of my setup. Secondly, after sticking my head next to the sub, I can say for certain that the sub is definitely LOUDER when I turn effects off. I can't understand why this should be with all other things being equal (meaning I'm not playing about with the speaker sizes). I must admit that I've never been unhappy with the sound from my setup, but in comparison the sound is definitely lacking when Pro-Logic is turned on. I have a suspicion (not yet tested) that DD and DTS sources may suffer in the same way. Any help/advice/useful comments would be very much appreciated. Villification of my choice of components will be borne with dignity. Thanks.