I have been fooling with my SM55 definitive speakers and have found that a crossover of 60hz seems suitable. I however have the problem that this takes away from my subwoofer (Definitive Pro Sub 1000). Is there a way to have both play the the 60hz to 80hz frequency. Also if that's not a good idea please tell me. I also have a Pro Center 1000, I just wanted to know if a 120hz cross over is good, or if I could get away with a 100hz crossover. My receiver is a Denon avr-x1400h.
Thanks for any help.
-Kyle Braunlich
It actually a common myth that multiple overlapping LF sources create response problems or bad sound. Not true, there is nothing wrong with this, as long as they are integrated properly. The problem is that many receivers and processor do not allow this. They use true crossovers and force you to set the mains as small with a symmetric hand-off between speakers. Something that might make sense with mid and high frequency drivers located close but makes far less sense with subwoofers far from the mains and with the period of the frequencies being very long.
The speaker you are using doesn't have a lot of dynamic range in the LF's, so while running it full range is probably the best option (and then using the subwoofer with an 80hz crossover). To make this work with most receivers, you would either need it to be a type that has some kind of "double bass" that allows subs and mains to operate simultaneously or use the main line-out of on the processor or receiver for the subwoofer and using the subwoofers own crossover. Once you have done that, you will need to make sure it's setup right, so you can certainly tune by ear if there is no other option. Measurements are nice, however, to allow you to optimize the integration. Muddy bass is very often caused by integration problems. With multiple LF sources there is greater problems with interference, so you need to be sure the phase and level is just right. Even crossover can be tricky. These aren't brickwall filters, so sometimes I will set a lower crossover than I want because the response is combining in an elevated fashion at the integration point.
My Geddes Subwoofer Youtube video discusses the theory and concepts that underly these ideas.