After reading a lot of other threads on FR and EQing for subs I thought I would give it a whirl myself. I used the spreadsheet from snapbug.ws as a start for my FR plots and also used the sine wave tones from the same site to make a test CD. Measurements were taken with the receiver set at -25dB in stereo mode, both sub+mains, mains are set to small and crossover is at 80Hz. I used a RS SPL meter attached to a "mini-tripod" and set on top of a box. It was angled slightly forward and ~3ft off the ground. This makes it pretty close to ear level when slouching on the couch and within 6" when sitting up.
I'm pretty limited in acceptable placement locations. My sub is an SVS 20-39CS w/ ISD and a 250W amp and is currently located along the front wall between the door to the garage and the LF speaker / RPTV. I also took measurements with the sub on either side of the couch.
Here is a picture of the room layout:
Ceilings are 9ft. Total volume for the LR + kitchen is ~3500cf. The room is open to the dining room which is an additional ~1500cf.
FR plot for sub in current position:
Things look pretty good from 20-36Hz but then drop off drastically until 80Hz, with the frequency for the bottom of the dip varying with seating position. This was a pretty deep and wide trough so I tried the sub in two other locations:
FR plot for sub on the left side of the couch:
FR plot for sub on the right side of the couch:
So, any advice on where to go next?
Kevin
