SVS SB13-Ultra Subwoofer


The SVS SB13-Ultra Subwoofer On the Bench

All the below measurements were in-room response. The distortion measurements were performed on-axis in the near field (microphone 1 foot from the center of the driver) to mitigate any room boundary effects. The frequency response tests were typically performed at 1-meter on-axis with one exception as described below.

The plot above is the standard in-room frequency response test of the SVS SB13-Ultra. This test result showed serious boundary and room-induced modal effects.


To demonstrate the level of performance possible with the SVS SB13-Ultra, I ran an additional test from the prime listening seat with the parametric EQ engaged. The above plot indicated a response curve of +/-5dB from 20–100Hz. As mentioned above, I was able to get this frequency response in about 30 minutes with a pen, a notepad, a Radio Shack SPL meter and a CD with test tones. Not bad at all!


At 80Hz and 100dB, the distortion (THD+N) was inaudible and measured only 0.22%.


Tested at 40Hz, the distortion rose slightly but was still remarkably low at only 0.33%.


The 31.5Hz plot was also clean and the measured THD+N was even lower at just 0.15%.


The measured THD+N at 28Hz was another very clean plot at only 0.33%. This was measured at 100dB as well. Below 28Hz, the distortion rose rapidly, but the sub was still capable of substantial output to 20Hz, albeit with a much higher measured distortion.