Specifications

Since several of the peaks and dips in this response are significantly above the crossover
frequency (63 Hz), the SMS-1 will be powerless to do anything about them because it can
only influence what the subwoofer produces.
The first stage in improving the sub’s performance was to get it positioned in the
optimum location. One traditional method of finding this is to play a bass-heavy CD with
the sub located in the main listening position and then crawl round the room on hands
and knees, listening for a place where the bass is tightest. With the SMS-1 you can make
this process a little more scientific (and less embarrassing) by placing the sub in the
listening position and just moving the microphone to potential sub positions while the
SMS-1 generates test sweeps and measures the room response.
Some examples of my experimental positions were the front left corner, rear left corner,
just inside the RH front speaker, and halfway down the right hand wall. Using the SMS-1
in this way demonstrated the huge difference that room placement makes to the
response, sometimes by moving only a few inches, and eliminated the guesswork
involved in finding an optimum position. A digital camera to capture the different
screenshots for later comparison is also a good idea.
Boosting dips in the response using EQ is best avoided because it tends to eat up
headroom from the subwoofer’s amplifier and/or lead to premature compression when
the sub is pushed hard. So, instead, you should reduce the peaks.
The best placement is generally where there are fewest significant dips. If this is not a
practical location, then you can choose the next best and so on. I chose to relocate the
sub just inside my right front speaker. Returning the microphone to the back of my chair,
I then re-verified that the response was the same with the sub and microphone positions