Velodyne Digital Drive Series subwoofer in stereo

Cary, I asked the professors because they are also in the hobby and definitely know a thing or two about audio, and both hold multiple Ph.D degrees in relevant fields.

Who should I ask if these professors aren't good enough? You?

Also, those little questions on your last paragraph would be insulting to ask them. Throw me a bone here.

I'm just another guy on the internet, so my opinion is as good as the next. I would suggest that you check out the some literature on Richard Vandersteen's site as he is a big proponent of stereo subs.

Dear Spacekadet: Velodyne: great choice nobody knows more about subwoofers that Velodyne people. I own two HGS-15, why two?: well not only because there are music information in the lef and right side of the recording signal but more important because those low bass ( left/right ) generate a lot of harmonics down and up the fundamental frecuency. So, if you have only one subwoofer you are missing a lot of music.

+++++ " except for a bump at 50Hz . " +++++

I can suggest that you can try other subwoofer position: side firing.

Now, the crossover point for the Totem's is very important ( critical ): which was your crossover point that you choose?

Regards and enjoy the music.
Raul.

I'm no professor but it seems to me you can't 'miss' any of the bass if you've summed the two channels through the sub. Its all there, how can you 'miss' any? Has anyone really compared two subs run in stereo to two subs daisey chained together? And can you honestly hear any difference or do you perceive it? I just can't believe there is. A benefit to having two subs though is another matter. I know two different people running two DD-18's in their systems... from what I hear, I want to match my single DD-18 to a sister sub... holy cow! Neither runs their other then daisy chained and both are knowledgable people in the industry.

Two answer your question, I have compared my two ULD-12's running in mono and in stereo. There is a difference. Remember that the left and right channel may have different phasing when picked up by the microphone. The most extereme example would be where the mike picked up the signal 180 degrees out of phase. This would result in no signal when summed to mono, when in fact there is a completely different signal from left to right. When played back the summed mono would have no output while the stereo subs will put out the signal and the listener will hear the bass as picked up by the microphone.