What process did you use to integrate multiple subwoofers for 2 channel listening?

@mapman

You have to jump ship on the measurements at some point.

I’m not sure if you’re giving me this piece of advice, because I mentioned (I thought), I’m going back and forth, measurements to listening to measurements, etc. Better measurements reveal themselves in a listening experience that reveals more than I was hearing before and it has raised my standards, both as a listener and in terms of what I knew my room was capable of. It’s easier to give me advice if I’m a "measurementalist" but there’s no way that impression could be fairly assigned to what I’ve been saying. Listening is the final test, because after all, I didn't buy a hifi rig so I could run sweeps!

Are these devotions from ruler flat response something you are hearing that affects your listening pleasure or is it something an electronic piece of equipment is telling you is not correct?

@arrowheadrss Not sure where I expressed a fixation on ruler flat response. That’s not realistic and I know it’s not desirable. I’m treating the measurements as one might treat a BMI reading. If it says you’re obese, well, who knows if that’s the right word, but it’s safe to think that dropping a few pounds is to your benefit.

Did you get a response 
from  The Benzman   ?

hilde 45, relative to Sub Woofer Placement 3 Subs are IDEAL!

Here's my solution for  optimization of results, with 3 subs.  

1) Set of 12 inch, self powered 500 Watt Subs at Far Left & Right of room, set @ 70 HZ Crossover.

2) Single 15 Inch Sub Directly in Center. This Sub Woofer is Fed its signal from a dbx 234S Electronic Crossover set @ 40 HZ Crossover Frequency, & set to SUM Left & Right Channel Inputs, which signal is in turn fed to a Classe 25 in Mono Mode, putting out an honest 1,000 Watts. dbx 234S gets its signal directly from the second output of my pre-amp.

3) Combined with PS Audio BHK Signature 300 Mono Blocks, feeding a pair of Anthony Gallo Acoustic 3.0's, three way speakers.

This combination of Speakers puts out Exceptional Non Boomy Bass with Massive Slam, as the 15 Inch Sub Woofer is driving directly into one, when they are sitting in the sweet spot.

I find the "Single Very Low Bass Sub", summing both Left & Right Bass signals to be optimum for Deep Bass, while not interfering with the music that one plays.

Try it, you will like it!

JI use the DBX Driverack VENU360. It has 6 analog outs (xlr), four which can be used for subs. Each sub can be “tuned” to your liking with delay, polarity, dB gain, off/on all from your laptop, phone or iPad. You can also control your two mains with “Q” control, graphic and parametric eq’s as well as all of the above options. It also has a subharmonic control that can be very useful.
I’ve been very leased with the results.
Did I mention it also has a built-dac? I don’t use it, but it’s there if you need it.

REW can do so much more when implementing the MiniDSP along with it, it's not just a sweeping tool, it's an all in one turn key solution. The Driverack is a great piece of equipment, I used the original 360 model back in the day in a professional environment,  but you can do all the things ( and more ) the DBX Driverack can for 20% of the price with REW ( free ) and the MiniDSP ( $205 ) for up to 4 subs.
You measure each sub separately then measure them all together ( gain matching should be done before you start ) and you can see the difference after all have been measured together. Then you start delay comparisons ( with sweeps ) and after you find the best combination of delays you go to the EQ section of REW and that's where the magic begins. You create a room curve of your liking ( you don't want total flat response ) and after going through the settings then hit the "Match the Target" and REW equalizes your original measurement ( of YOUR room with all it's acoustic anomalies )  to the "room curve" you've determined. It has used a 10 point parametric EQ to do it ( including Q control ) and you can continue to manipulate it ( and if it didn't use all 10 points you can add to it ) to make it better.
I'm sure you have had successful  improvement from just using the sweeps and adjustments you made but REW / MiniDSP will take it to the point your attempting to get to. You will be absolutely amazed and will enjoy your 2 channel system in a way you hadn't even imagined.