I just purchased a Denon AVR-1508 and the Take Classic 5.1 Home Theater package.  I know that the manual for the subwoofer states that if your reciever has a single subwoofer out (which the Denon does) to only hook one RCA input to either the Right or Left channel of the subwoofer.  I have a monster cable Y-adaptor male to two female, and have plugged this into the subwoofer out of the reciever, and two monster RCA cables into both the Left and Right channel of the subwoofer.  I noticed an increase in volume from the subwoofer.  So two questions here.

1) Is this going to cause an issue with the subwoofers amplifier?

2) If this isn't going to cause an issue with the amplifier then why not simply recommend this as a standard setup?

I don't know the tech details of whether or not doubling the input to the sub is unwise.  I would say that if in order to get the right balance of low end in your sound that it seems like you have to turn down the sub volume to well below nominal, then I'd stick with a single in.

Steve   

Thanks for the thoughts!  It just seems to me if I have to push the internal amplifier less to get the same sound, then to me it seems to make sense.  I just want to make sure that it is not going to cause any issues with the subwoofers internal amplifier by doubling the input. Especially since the Energy configuration recommendations advise only to use one input via a single subwoofer out.  As far as setting the sub volume below nominal, I truely don't think that is the case, with splitting the input, the volume is set to about 1/2, with single input it is about 3/4.  I would suspect half would still be considered optimal output from the internal amp?