Originally Posted by AustinJerry
Not Keith, but as long as you understand what you are doing, there shouldn't be an issue. Connecting channels 1 and 2, invoking bass management, and turning off the left and right speakers will route the REW test sweep to the connected subs. Connecting channel 4, which is the LFE channel IIUC, would route the REW signal to the subs as well. In theory, both should yield similar results. Remember, there is a HPF of 120Hz (or lower for some people) on the AVR's LFE channel.
Minor nitpick, Jerry: most modern AVRs have an adjustable HPF up to 120 Hz for the LFE channel. Certainly Audyssey-equipped AVRs do, above and beyond any speaker-specific crossover settings.
But not all....ask a Pioneer user, for example. IIRC their LFE HPF is determined by the crossover setting for the mains, and the LFE rolls off at 12 db/octave after that point. In practical terms, that works out to about 120 Hz for an 80 Hz crossover point, with 118 to 124 Hz as the -6 db point - exact Hz depends on the AVR. But if one were to use a lower crossover, e.g. 50 Hz, you'd be down more like -12 db or worse at 120 Hz.
If anyone's curious: http://www.avsforum.com/t/1112470/official-pioneer-mcacc-thread/4110
I have a similar issue with the R-972 I'm testing. They use a measured F6 point for the subs on the high pass to help determine speaker crossover points, relative to the observed F6 low pass for satellites. Not sure I really that, since I'm still working out where that takes us given the dips you see in sub response > 100 Hz on REW. If I wind up with consistently crazy crossovers, such as 200 Hz for my powered Mythos STs (currently 80 Hz with XT32) after a Trinnov run, I might have to reconsider some positioning things. I've learned to like my 100 Hz crossover for my centers, and 120 Hz for my surrounds, but I draw the line with 100 Hz+ crossover for mains.Edited by sdrucker - 9/10/13 at 12:26pm