Stereo Integrity HST-15 15 inch subwoofer, front view of the carbon fiber cone and dust cap
Stereo Integrity HST-15 side profile of the cast basket and tall stacked motor
Stereo Integrity HST-15 rear three-quarter view of the motor and cast basket
Stereo Integrity HST-15 mkIII Klippel report of force factor Bl(x) and suspension stiffness Kms(x)
Stereo Integrity HST-15 15 inch subwoofer, front view of the carbon fiber cone and dust cap
Stereo Integrity HST-15 side profile of the cast basket and tall stacked motor
Stereo Integrity HST-15 rear three-quarter view of the motor and cast basket
Stereo Integrity HST-15 mkIII Klippel report of force factor Bl(x) and suspension stiffness Kms(x)

Stereo Integrity

Stereo Integrity HST-15 | 15 Inch Subwoofer

SKU: SI-HST15-D1

$ 1,199.99
QUICK SPECS
  • Type: 15 in high-excursion subwoofer, sold individually
  • Excursion: 40 mm one-way linear, 102 mm total peak
  • Motor: 250 mm triple stacked, three shorting rings
  • Displacement: 0.45 cu ft for enclosure modeling
  • Impedance: Dual 1 ohm or dual 2 ohm
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Stereo Integrity HST-15 15 inch subwoofer, front view of the carbon fiber cone and dust cap

Stereo Integrity HST-15 | 15 Inch Subwoofer

Includes Shipping On orders to the lower 48
Full Warranty Factory Backed
Expert Support Real Installers
INSTALLER'S TAKE

Same HST recipe in a 15 inch frame: 250 mm triple stacked motor, three shorting rings, bifilar copper coil, 40 mm of one way linear travel and 102 mm of peak excursion. This series makes its output with stroke rather than cone area, which is why the motor is so large relative to the basket.

One number is published here that the HST-18 lacks, and you need it: driver displacement of 0.45 cubic feet. Add that to whatever net volume you are targeting. Beyond that SI do not list a full Thiele Small set, a power rating or mounting dimensions, so do not design a cabinet around assumptions. Call us first.

The Klippel report in the gallery is worth your time. The force factor and suspension stiffness curves tell you more about how this driver behaves near its limits than a parameter table would.

Hand built to order, dual 1 or dual 2 ohm, roughly 90 pounds shipped.

Product Details
Specifications
Enclosures
FAQs
Related Video
Product Details

Stereo Integrity

HST-15

15 Inch High-Excursion Subwoofer | Sold Individually

40 mm One-Way Linear Travel 102 mm Peak Excursion Triple Stacked 250 mm Motor Carbon Fiber Cone Dual 1 or Dual 2 Ohm

Long Stroke in a 15 Inch Frame

The HST-15 brings the Stereo Integrity HST series design to a 15 inch cone. The series is built for very large bass output from very small enclosures, and it gets there through stroke and motor force rather than cone size. The bifilar copper voice coil is capable of 40 mm of one-way linear travel, for 80 mm of total linear travel and 102 mm of total peak excursion.

Each HST-15 is hand-built by Stereo Integrity in North Carolina. For enclosure modeling, Stereo Integrity specifies a driver displacement of 0.45 cubic feet.

Engineering Highlights

250 mm Triple Stacked Motor

A large triple stacked motor with three shorting rings provides the force to control a cone moving this far, which is why the motor is so tall relative to the basket.

Bifilar Copper Voice Coil

The bifilar copper coil delivers 40 mm of one-way linear travel, with the shorting rings working to hold inductance down across the stroke.

Flat, Linear Suspension

A wide soft foam surround and a three layer, 10 inch natural Nomex spider keep compliance flat and linear, and sewn-on flat voice coil leads eliminate lead tap.

Carbon Fiber Sandwich Cone

The carbon fiber sandwich cone and dust cap keep cone stiffness very high, mounted in a high-clearance cast aluminum frame with large 4 AWG push terminals.

Choosing Your Version

The HST-15 is available in dual 1 ohm and dual 2 ohm. Wire dual 1 ohm coils to 0.5 ohm in parallel or 2 ohms in series, and dual 2 ohm coils to 1 ohm in parallel or 4 ohms in series.

Planning note: Beyond the 0.45 cubic foot displacement, Stereo Integrity's product page does not list a Thiele-Small parameter set, power rating, or mounting dimensions for the HST-15. The Klippel report in the gallery shows its measured force factor and suspension stiffness curves. Call us before you plan an enclosure and we will help with the details.

Ordering

Each HST-15 is hand-built to order and ships separately. Stereo Integrity lists a 90 pound shipping weight, so call 931-563-5151 before you order for current lead time and delivery options.

Authorized Stereo Integrity Dealer

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

Call 931-563-5151 to plan an HST-15 build.

Specifications
Specifications
ModelHST-15
Size15 in
Voice Coil OptionsDual 1 ohm or dual 2 ohm
Voice CoilBifilar copper
Motor250 mm triple stacked, three shorting rings
SpiderThree layer, 10 in natural Nomex with sewn-on flat leads
SurroundWide soft foam
ConeCarbon fiber sandwich cone and dust cap
FrameHigh-clearance cast aluminum
TerminalsLarge 4 AWG push
Driver Displacement0.45 cu ft
Listed Shipping Weight90 lb
Published Excursion
Linear Excursion (Xmax)40 mm one-way
Total Linear Travel80 mm
Total Peak Excursion102 mm
Figures as published by Stereo Integrity, which does not list a Thiele-Small parameter set, power rating, or mounting dimensions for the HST-15.
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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