Hi just a quick question. I have my active sub set at 80hz and the volume set at just under half maximum. This sounds correct for the cd palyer and the xbox 360 but when I watch a dvd through the dvd palyer(not the xbox 360 it is a seperate) its like the sub isnt even on. I have to change the volume up to 3/4 of max for it to sound same as cd palyer and xbox 360. Is this normal? Is it just because the way the bass signal is output on dvd's is different and i do need to increase the volume on the sub to make it sound correct or is it normal for the sub to be so quite?(as the volume is correct for the cd palyer and xbox 360) any thoughts?

Do you have a receiver that the sub is hooked up to? Many receivers retain separate level settings for different inputs, so you may just need to calibrate your system using a DVD.

the av reciever is quite old. The dvd palyer has the dolby digital decoder reciever and then thes siganl goes into the av reciever(as does the xbox 360 and cd player). I can't change the level settings on the dvd player input. So i guess what im asking is if the receiver is is out putting the xbox and cd player sound correctly with the sub at the above settings. Is it just right for the sub to sound different(very quiet) on dvds. Or am I right to increase the volume on it so its sounds the same as the cd palyer and the xbxo 360? Bit of strange set up and quetion but just want your ideas. It seems strange the sub sounds different to me!

Also, remember consider that different DVDs (movies) will play at different levels. Typically, older films will have a less LFE response. Some newer ones might be over done. Remember also to check how your receiver responds to how you set your speaker settings - large or small. Sometimes, as with Denon once you set our center to large it almost completly shuts down our sub - unless your sharring the lower frequencies between the two. Even if your reciever doesn't shut off the L.F.E. channel it might cut it back a bit.
Also, some sub require a "Y" cable to split the signal input coming from the receiver.