Originally Posted by Floydster
What is BFD? 24 bands sound great, but how would you connect it. I'm looking to increase my setup to 7.4. There are only two subwoofer channels (left and right) on my TX-47 Pioneer Elite. I can see connecting the two front subs to their respective back subs by inputting the pre-out on the front subwoofers to the pre-in on the back subwoofers, but how would you connect an equalizer into this mix?
Also, self-powered subs have their own volume and 12db/octave cut off points. The only thing missing is signal delay because of different distances, and I haven't seen (doesn't mean there isn't one) an equalizer that would allow delay adjustment.
BFD is the Behringer Feedback Destroyer (the old DSP1124P in my case) - one of it's purposes is to kill feedback in live presentations. But much more entertaining is as a digital 24-band parametric eq. (12 filters per channel if running two channel). You can independently adjust frequency, bandwidth and gain for each of those 12 points per channel, which gives phenomenal ability to tame room nodes and achieve exactly the curve you're looking for. Cost was under $200 (not sure about the newer models). The only downside is no adjustment below 20 Hz.
In my theatre I'm using the SC25, which just has one sub output. I've got three subs connected, and use the BFD's to roll out exactly the bass response I'm looking for. I just split the signal from the receiver, and then roll my two big subs through the BFD. In your case, you could use two BFD's to equalize them all, or if they're placed in pairs, just use one.
There are threads here and on other forums about using the BFD's in this way (how to measure and what adjustments to make). Results are SPECTACULAR! Which is why I'd like to see Pioneer increase their game in this area.
oops - Mark beat me to it, so, ummm, yeah, what he said!