Best ways to optimize setup

[nelmr]

Okay I just bought a new receiver (should be about 5dBs more headroom), which gives me more flexibility to actually use my nearly full range fronts/rears.

My room and adjoining open areas come to about 5300 cubic feet. My SVS PCi 20-39 isn't powerful enough to do -10dB reference level. So I have it turned down about 6 dB lower than my speakers. I was wondering if I could utilize my fronts/surrounds to help increase bass response in my room? Would this be feasible?

My mains are have a -3dB rating down to 35HZ and my surrounds 40hz. Should I set the crossover to those values? Would this help improve bass response in the room? What about placing the sub behind on of the mains? Would the collocation of the sub plus the speaker help?

Alternatively, I've heard that a crossover at double the extension point is usually a good idea (70 and 80 respectively). Maybe I'm remembering wrong. What sonic penalty would I have by crossing over at 35, and 40? Aside, from Doppler distortion that is.

Any other suggestions on improving bass response in my room (without buying a new sub) would be helpful. I think I'm also in a null where I sit at as well. Here is a diagram:



Also....

Do you think there would be any benefit to using 6.1 (see diagram), or would 5.1 be better? I have a spare speaker that was originally part of the pair when I bought the center channel bookshelf. I didn't run 6.1 due to the poor performance of my previous receiver (34 watts 5 channel continuous vs. 112w 5 channel / 100w 7 channel for the new receiver).

 

[Zing]

I have just barely enough knowledge to address your crossover questions. Most everything else should be addressed by those smarter than me (which is nearly everybody).

You're on the right track about doubling a frequency for a crossover point but I think you have that particular frequency wrong. It's not the +/-3dB point but the low frequency cutoff point, which is usually -6dB or -10dB.

If your speakers have a +/-3dB rating down to 35Hz, their LF cutoff is likely somewhere around 30Hz. That's the number you should double to determine the crossover point. That will ensure the best possible performance from your speakers with the least amount of distortion. However, if you don't listen to material at very loud levels, you could easily get away with a lower setting, say, 50Hz. But the lower that setting, the less headroom you're going to have because your amp will be working harder and harder to play the lower frequencies.

Unless your speakers are unusually efficient (>90dB), I'd set the XO higher to maximize both amplifier and speaker performance. And unless you run something like True RTA to see the effects of XO settings, I wouldn't go higher than 80 or 90Hz.

All that said, I don't think directing more bass to your speakers will improve the bass response. That's likely room dependant so all you can do to change that is change the location of the speakers and sub. Sometimes just a few inches will make a dramatic difference. Again, without the benefit of RTA, you really won't know whether you made something better or worse. I suppose that's where Audessey comes in, if - IF - you trust it.

 

[nelmr]

The mains are 93dB/watt/meter and the surrounds are 92dB. The amp should be capable of about 110watts (Denon 3310CI, rated at 120watts) in my 5 channel setup. Here is the frequency response chart for my mains:

 

[yromj]

First of all :text-welcomeconfetti: it's good to see you hear nelmr.

I agree w/ Zing. I would set the cross-over around 60Hz and let my sub do the best job it can do. If you upgrade then you'll get the extra oomph you're looking for. Your mains and surrounds simply won't give you what you're looking for in the bottom end. All that will really change if you continue to lower the cross-over frequency is blurred mid-range because of the issues we discussed on the other forum.

John