Stereo Integrity SQL 15 Series 2 subwoofer, front view of the paper cone and logo dust cap
Stereo Integrity SQL 15 subwoofer, side profile with the cone facing down showing the motor and basket arms
Stereo Integrity SQL 15 subwoofer, rear three-quarter view of the vented motor
Stereo Integrity SQL 15 subwoofer, rear view of the motor and spring-loaded terminals
Stereo Integrity SQL series close-up through the basket window showing the copper voice coil
Stereo Integrity SQL series close-up of the voice coil and spring-loaded terminal
Stereo Integrity SQL series close-up of the spider with stitched flat lead wires
Stereo Integrity SQL series Klippel force factor Bl(x) measurement
Stereo Integrity SQL 15 Series 2 mechanical drawing with dimensions
Stereo Integrity SQL 15 Series 2 subwoofer, front view of the paper cone and logo dust cap
Stereo Integrity SQL 15 subwoofer, side profile with the cone facing down showing the motor and basket arms
Stereo Integrity SQL 15 subwoofer, rear three-quarter view of the vented motor
Stereo Integrity SQL 15 subwoofer, rear view of the motor and spring-loaded terminals
Stereo Integrity SQL series close-up through the basket window showing the copper voice coil
Stereo Integrity SQL series close-up of the voice coil and spring-loaded terminal
Stereo Integrity SQL series close-up of the spider with stitched flat lead wires
Stereo Integrity SQL series Klippel force factor Bl(x) measurement
Stereo Integrity SQL 15 Series 2 mechanical drawing with dimensions

Stereo Integrity

Stereo Integrity SQL 15 Series 2 | 15 Inch Subwoofer

SKU: SI-SQL15-D2-PAPER

$ 475.99
QUICK SPECS
  • Type: 15 in SQL subwoofer, sold individually
  • Power Handling: 1000W RMS
  • Impedance: Dual 2 ohm or dual 4 ohm
  • Enclosure: 2 cu ft sealed, or 4.25 cu ft ported at 22 Hz
  • Mounting Depth: 7.4 in, 14.17 in cutout
Stereo Integrity SQL 15 Series 2 subwoofer, front view of the paper cone and logo dust cap

Stereo Integrity SQL 15 Series 2 | 15 Inch Subwoofer

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Product Details
Specifications
Enclosures
FAQs
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Product Details

Stereo Integrity

SQL 15 Series 2

15 Inch Sound Quality Loud Subwoofer | Sold Individually

1000W RMS 2.75 in Copper Voice Coil Dual 2 or Dual 4 Ohm 2 cu ft Sealed Paper or Carbon Fiber Dust Cap

More Cone, Same SQL Recipe

The SQL 15 Series 2 carries the Stereo Integrity SQL formula to a 15 inch cone. It has 127.6 square inches of piston area, compared with 82.51 on the SQL 12, so it moves considerably more air while keeping the motor, coil, and suspension design that defines the series. Stereo Integrity designed the line in Finite Element Analysis software and verified the coil and mass balance on a Klippel system.

Like the rest of the SQL series, it is built to lay down an accurate sound quality foundation and still hit hard when a track demands it. Stereo Integrity recommends 2 cubic feet sealed or 4.25 cubic feet ported.

Inside the SQL 15

Overhung SGLC Motor

The SQL 15 uses the series SGLC overhung motor with a 2.75 inch solid copper voice coil on a split, black anodized aluminum former. A solid aluminum Faraday ring inside the Y35 ferrite structure reduces inductance so transients stay quick.

Balanced Coil Size

At 2.75 inches the coil sits between the usual 2.5 and 3 inch sizes, keeping inductance below a 3 inch coil while making more motor force than a 2.5 inch coil.

Dual Nomex Spiders

Two 8 3/8 inch Nomex spiders give an even compliance curve through the linear stroke and stiffen near the limit to handle extra excursion. Mirrored, stitched-on flat lead wires keep the coil from rocking.

Treated Paper Cone

The naturally dried, treated paper cone and tall roll rubber surround are matched to the spiders so the suspension stays balanced as excursion climbs.

Enclosure and Power

Stereo Integrity rates the SQL 15 at 1000 watts RMS. Its sealed recommendation is 2 cubic feet, and its ported recommendation is 4.25 cubic feet tuned to 22 Hz with 20 square inches of port area. The driver displaces 0.16 cubic feet.

Built for this driver: Proline X builds Performance Optimized sealed wedge enclosures for the SQL-15 in single and dual configurations, plus a ported wedge, at our shop in Tennessee.

Shop Proline X Enclosures for Stereo Integrity

Choosing Your Version

Dual 2 ohm coils wire to 1 ohm in parallel or 4 ohms in series, and dual 4 ohm coils wire to 2 ohms in parallel or 8 ohms in series, so choose the version that matches the load your amplifier wants.

Paper and carbon fiber dust caps are both available. Stereo Integrity publishes one specification set for the SQL 15 and does not list separate figures for either dust cap or impedance.

Fitment

Cutout: 14.17 in. Outer diameter: 15.55 in. Mounting depth: 7.4 in. Displacement: 0.16 cu ft. Stereo Integrity lists 1.25 in from the baffle to the top of the surround.

Authorized Stereo Integrity Dealer

Audio Intensity is an authorized Stereo Integrity dealer, and we build enclosures around their drivers.

Call 931-563-5151 and we will help you match the SQL 15 to the right enclosure, amplifier, and install.

Specifications
Specifications
ModelSQL 15 Series 2
Size15 in
Voice Coil OptionsDual 2 ohm or dual 4 ohm
Power Handling (RMS)1000 W
Voice Coil2.75 in copper, 50 mm winding height
Cone / Dust CapTreated paper cone, paper or carbon fiber dust cap
SurroundTall roll rubber
MagnetFerrite (Y35)
Outer Diameter15.55 in
Cutout14.17 in
Mounting Depth7.4 in
Driver Displacement0.16 cu ft
Baffle to Top of Surround1.25 in
Weight28 lb
Thiele-Small Parameters
Resonant Frequency (Fs)33.0 Hz
DC Resistance (Re)3.2 ohm
Voice Coil Inductance (Le)2.5 mH
Electrical Q (Qes)0.61
Mechanical Q (Qms)7.60
Total Q (Qts)0.57
Equivalent Compliance (Vas)59.4 L
Effective Piston Area (Sd)127.6 sq in
Force Factor (Bl)20.3 Tm
Moving Mass (Mms)374.9 g
Linear Excursion (Xmax)26 mm one-way (70% Bl)
SPL91 dB
Enclosure Recommendations
Sealed2 cu ft
Ported4.25 cu ft tuned to 22 Hz
Port Area20 sq in
Figures as published by Stereo Integrity, which lists one parameter set for both impedance versions.
Enclosures
FAQs
Related Video

No video available for this product yet.

Check back soon, or reach out and we'll walk you through it: 931-563-5151

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