Large speakers plus EQ, what have you done?

I’ve had awesome results with my new Danville dspNexus with newly released SHARC processor playing 8 channels with 12 biquads per channel. I have 20.1 Magnepan speakers running full range (no passive crossovers except the internal tweeter) and four subwoofers, two towers up front with five 10” Seas subwoofers in each, wired parallel with sealed enclosures, and two 16” SVS SB-16 Ultras in the room. The biquads are IIR filters to reduce processing stress, they round to 10 decimal places so they are extremely accurate. 

I measure each speaker independently at the listening position with an Earthworks 30Hz-30KHz with Room EQ Wizard and put the results into Multi Sub Optimizer. I let all speakers play full range. I then hook up my fast computer and let it chug for a few hours to make the best room correction adjusting for time alignment, phase, and amplitude. I then take those results and plug the numbers into my DSP. The sound is the best I’ve heard. I listen to music and movies at loud volumes and the neighbors have never complained because the sound is so well controlled through the DSP and multiple subwoofers.

I think this is the best way to get accurate sound but I know that the barrier into technology could be intimidating. One has to be careful with active amplification not to cross wire speakers and blow them out. I recently tweaked the dB levels between the front and rear subs by 3dB to add a little more low end oomph and love the results.

I think this is a great topic! Thanks for putting it out there. I wish it was present when I started trying to learn about active amplification and DSP.

I get very good bass out of my Revel Salon 2s. But when I want more, I use the parametric EQ function in JRiver to boost bass by a couple of dB at 100 and 500 Hz bands. Does the trick pretty well.

An additional non-software tweak that really helped bring the low-end oomph was putting the Revels on Star Sound Apprentice XL stands - but that involved hardware, so probably outside of your area of inquiry.

@p59teitel  - Good to hear, sounds as if you had very few room issues to deal with. Lucky you!

Actually I think most audiophiles would find the large amount of glass in the sunroom quite troublesome to dial in the typical “you are there” sound (it does help to have a cathedral ceiling with the sound able to disperse adequately and not just ricochet). My approach is “they are here” and between Revel and the Symphonic Line source and amplification gear, it works for me.

You can "eq" the speakers through component selection in the crossover (even if unintentionally) and this is probably why some people prefer passive crossovers to active crossovers.

Case in point. All the values in the crossover have an "ideal" combination, but the combination can be tweaked to produce a hump or a dip in an area of the band that is pleasing to the listener.

The 5.8 mH choke with an 8 ohm load would actually like to "see" a 44 mfd cap to ground. A larger cap (e.g., 47 mfd) will create a greater roll-off, but it will also create a hump just below the crossover frequency. The larger the change from "ideal", the larger/broader the hump. So if you set the crossover to the "right" frequency and you "over-capacitor" it, you can add a "hump of bass" just below this frequency (which I have at 310 Hz).

Similarly, the combination of C2, C3, and C4 if "over-capacitored" will increase the roll-off, but create a hump below the crossover frequency, which puts it at ~1kHz where the ear is most sensitive.  This takes a bit of the high end hash out of the 2251 while giving voices a warmer, more pleasant tone.