Time well spent with REW


I spent a few hours tweaking my dual sealed servo subs using REW. Amazing what a few iterations of adjust/measure/repeat can achieve even with sub optimal room dimensions and decay.

The final values are simply not anything one could guess or happen upon through listening and experimentation. No two settings are the same on the two subs.

Volume, phase/delay, x-over - all different, some only slightly but made a significant difference in measurements.

LPF slope and bass ext - these ended up the same but I tried all combinations. With 3 variable dials and two switches, one with 3 settings there a bunch of combinations to try.

The subs are not symmetrical in relation to my listening spot but are pretty close to symmetrical in the space.

My mains are asymmetrical in the space. Fact of also using it as a living room.

The room modes are pretty clear, resonance at 45hz and nulls at 80, 100 and 140, 180hz…convolution will knock down the peaks with little damage.


From your graph my guess is that your room is 15’-8" x 25’-8".

Have swept my room and have peaks at 52 and 83 Hz, which correspond to my 13ft x 21ft room (dividing speed of sound, 1130 ft per second, by frequency peak). Trying to tame them as much as possible without DSP (having always felt that DSP should be the last step after proper room shape and treatments). So moved six panels of Owens Corning 703 high density fiberglass to front/back walls and dropped the 52 Hz peak by 6 dB!

Note that I use 3 subs to reduce in-room bass peaks/dips.


My space is 14’ x 19’ x 8’ with 2 openings and one entry way that creates a bit more space.

I have 2 4" Gik 244 under and behind my main listening position and made a panel using 2" rock wool that is 5’x3’ covered in fabric that I had printed with a nice photo.

Definitely helps. I’m going to evaluate 2 PSI AVAA units at the end of the month, though I only have 1 location that the wife will allow as it will be disappeared.