REW Dual Subwoofer Placement 

I continue to appreciate your hard work to optimize an HT system. What is important when you make this kind of operation ? Be sure of your measurements, it means you have to repeat a second (third, fourth, till tenth if you want to be more confident) time the same configuration. Between each measurement of repeatability, unmount the setup. Like that you'll be able to check your error of measurements. The peak (you measure close to the couch) which go down like a comb filter activated come probably from the couch because it absorbs different frequencies. If you move the couch, it should affect the response curve. If not, try to find the root-cause to identify the element. Sometimes it comes from the room itself. Unfocus this step by step optimization with these measurements, what you'll discover with a long time ? An acoustic treatment is better than all EQ and the benefit can reach 10, 20dB on several frequencies and you won't pertubate the original signal of your recordings. To boost the low frequencies, damp correctly the room is the key point. One tip to finish : don't opposite the direction of waves or you'll get a "cancelling" phenomenom.

I have dual SVS SB4000's and went through a very similar exercise with placement. Options are limited in my room but I was surprised how much difference phase alignment made. Still have work to do with the PEQ's but I have already managed to achieve a reasonably decent combined response. Thanks for another great video!

Unfortunately I'm restricted as to where my dual subwoofer configuration can be placed but that's where PEQ definitely saved the day. In the end I was able to get within ±3db from 20Hz-110Hz.

Does it matters if there is a deep at 150 hz don’t you use the subs below 120 hz?

phase are the same?

Change the frequency range in REW to 10 Hz - 200 Hz when doing sweeps in the bass region, no use showing out to 20kHz

I know it’s a stretch and definitely not ideal, I do not have a functioning computer, all 5 are dead LOL. If I could borrow a friends laptop, could I use the Audyssey mic for REW?

Were you time aligning the subs each time you moved them? You always need to delay/phase/time align the two subs. You will find that just tweaking the phase on one of them, you will ensure the combined output is fully doubling, rather than slightly summing or even subtracting - never mind... just caught the end of the video and you mention you will use the phasing in the next tweaks.

I currently suffer from terrible bass at my main listening position. And I only have one big sub. It's a dual opposed dual 18" sealed subwoofer from Power Sound Audio. While there's TOO MUCH bass in the rear quarter of the room, my main listening position is suffering through some nasty nulls. My sub is placed at the left front 1/4 position between my Left and Centre channel speakers. Doesn't matter where I place the sub, the response sucks at the main listening position. So My only option is to buy another sub at this stage which will set me back a lot of $$$ to get something similar to what I have.

I'm sure you have acquired the MiniDsp HD by now...being able to measure with Rew is the diagnosis, but the MiniDsp is the actual treatment, 10 band peq plus 80 milliseconds of Delay is incredibly powerful, I have The flattest smoothest response that can be achieved, will email photos

Those subs are Big

Use Control to hit fit data to screen, you are not able to see your trace in detail.

I'm putting the same comment on all the subwoofer reviews on the internet . After recording bands for 30 years standard practice is to put the kick drum and the bass guitar in the middle. Therefore one subwoofer works just fine. However if I record an unconventional band and let's say they want the upright bass to be in the Left Channel and the drums to be in the right Channel and you only have one subwoofer you are not getting stereo Bass. Bass Can Be stereo just like if you had two big speakers with 12 inch woofers and no subwoofer . Get two put them outside of your main speakers. Enjoy stereo Bass

Loud music at introduction so we have to strain our ears to hear what you are saying. Why?

Your intro music is way too loud when you start talking.