SVS 25-31PC+ 25 Hz tune (dB12.2)

[Ilkka]

Manufacturer: SVSound
Model: 25-31PC+
Provided by: Arttu78
Manufacturer link: SVSound - Cylinder Subwoofers
Price: $775

Manufacturer specs:
Proprietary TC-Sound 12" high output woofer
Computer Assisted Design (CAD) enclosure
Flush-mount, internal 525 watt BASH amp
Exclusive down-firing cylinder design
Compliant floor mounts, low center of gravity
"Tri-Power" 3" High-flow ports with port block
User variable tuning: 25 Hz (stock), 20 and 16 Hz
Resonance free, protective top grill
High-strength polymer wrapped enclosure
CNC'd black laminated, 1.5" birch end-caps
Architectural-grade black fabric exterior
Dimensions: 32" tall, 16" diameter
Weight: 23 kg
+/- 3 dB 25-100 Hz (25 Hz config) quasi-anechoic response (in-room extension will be 3-4 Hz deeper)

Configuration as tested:
Phase: 0 degrees
Tuning frequency: 25 Hz (no port plugs)
Subsonic filter: 25 Hz
Orientation: Standard down-firing
This unit uses dB12.2 woofer

[Ilkka]

+/- 3 dB points: 24.5 Hz - 82 Hz

[Ilkka]

[Ilkka]

The smallest one of the SVS cylinders. The shape of the frequency response is rather unique with a hump centered at 35 Hz and a sloping response above it. Add a typical low frequency room gain, and the lower mid bass/deep bass becomes quite pronounced. The crossover works as promised and has a steep enough slope for 2-channel use. The subwoofer has a good mid bass output, peaking just above 105 dB. The deep bass output is compromised because of the 25 Hz tuning frequency. The power compression grows rather large around the tuning frequency which suggests that the subwoofer is somewhat under ported. THD stays really low down to ~25-28 Hz. THD consists mainly out of 2nd order component. Group delay starts to climb up below 50 Hz, but it shouldn’t be audible due to shallow rise. Spectral decay shows a little bit less ringing than is typical for a vented subwoofer. Spectral contamination test shows higher than average maximum output with low overall distortion. The cylinder design is pretty light, which can be prone to “walking” at extreme output levels. Also not everybody like the look of it. With a small frequency response shaping it could become a very good subwoofer.

+ Relatively good extension
+ High mid bass output
+ Low overall distortion at all output levels
+ Overall price/performance ratio

+/- Look and weight of the cylinder
- Shape of the frequency response
- High deep bass group delay