I have an agenda? What would that be?
And from what I have read so far, I bet you don't hear any difference in components all things being equal.
The first thing I do to even out low end response is to buy two or more subs depending on the situation. Then if need be I go to dsp. As far as a flat response curve goes I wouldn't be boosting a 20hz signal as it requires the driver to make massive movement thus the x-max may run out of linear motion, bringing on high levels of distortion. Plus it makes hugh demands on your amp, consinquently shortening its life.
I would suggest a Dspeaker product 8033. I think the price is around $400 new. Sometimes they show up on A-gon used. A suggestion to the OP. Instead of moving your sub around ,try putting the sub as close to the listening spot or right in the chair and walk around the room to listen for the better/best place it sounds to you. Can save you a lot of time.
Btw, has the OP talked to Jim Salk about your problems. He may be able to be of immense help. Just a thought.
Well, when you make a statement in the manner you did, with the tone you did, it makes it seem like you have an agenda. In this case, what could easily infer that this is your agenda: "Hey everybody, look at me. I need attention, and I am smarter than everyone so listen to me."
If that wasn't how you intended to come across, perhaps you should have thought things through before posting. And then when you make foolish statements claiming I can or can't hear the difference between components...well, it's easy to write you off as someone with intentions to cause mischief. Again, it was your approach.
We already know you can smooth out the response with multiple subs. If you read the thread, you'd already know that the OP did have the sub in close proximity to the LP, and the low end response was poor. He tried different locations and found the best one to work with. There is nothing wrong with applying EQ below the Schroeder Frequency, something Floyd Toole and Sean Olive themselves are proponents of. It also doesn't matter that the Behringer is used in the pro audio arena. It does what it needs to and doesn't add additional noise or distortion to the signal chain.
Again I'll say, if you had actually read the thread you see that I warned the OP about boosting at 20Hz using a wide bandwidth filter, explaining it can cause amp clipping and possible driver damage. He is, however, using one of the best drivers available paired with a powerful amplifier. I know people who are boosting over 10dB at 20Hz using the same LMS driver with weaker amps in a larger room that have zero issues at reference levels. Circumstances are different for everyone, so experimentation is key. It is very possible that chargedmr2 will run into issues by using a wide bandwidth boost at 20Hz, but it is also possible he'll have no issues. Remember, he isn't boosting a null. So hey, why don't we let chargedmr2 weigh his options and make his own decisions, eh?
The 8033 is a decent unit, but it's not worth the extra $300 over the Behringer or MiniDSP unit. It won't sound any different between 20 and 100hz either.
Finally, in this audio hobby you most certainly do not always get what you pay for, so your statement is incorrect. I respect your opinions, but when you state them as fact and then make back handed critical comments towards others you come across as a troll. Calm down and share your options in a respectful manner, just like the rest of us.