Stereo Integrity TM8 8 inch midbass, front view of the cone and dust cap
Stereo Integrity TM8 midbass, angled front view of the cone and rubber surround
Stereo Integrity TM8 midbass, rear three-quarter view of the motor and terminals
Stereo Integrity TM8 midbass, low rear view of the cast basket and terminals
Stereo Integrity TM8 midbass, rear view of the motor and terminals
Stereo Integrity TM8 frequency response measurement
Stereo Integrity TM8 Klippel force factor Bl(x) and suspension stiffness Kms(x) measurements
Stereo Integrity TM8 Klippel voice coil inductance Le(x) measurement
Stereo Integrity TM8 cross-section drawing with mounting dimensions
Stereo Integrity TM8 front mounting drawing with bolt circle
Stereo Integrity TM8 8 inch midbass, front view of the cone and dust cap
Stereo Integrity TM8 midbass, angled front view of the cone and rubber surround
Stereo Integrity TM8 midbass, rear three-quarter view of the motor and terminals
Stereo Integrity TM8 midbass, low rear view of the cast basket and terminals
Stereo Integrity TM8 midbass, rear view of the motor and terminals
Stereo Integrity TM8 frequency response measurement
Stereo Integrity TM8 Klippel force factor Bl(x) and suspension stiffness Kms(x) measurements
Stereo Integrity TM8 Klippel voice coil inductance Le(x) measurement
Stereo Integrity TM8 cross-section drawing with mounting dimensions
Stereo Integrity TM8 front mounting drawing with bolt circle

Stereo Integrity

Stereo Integrity TM8 | 8 Inch Midbass - Pair

SKU: SI-TM8

$ 499.99
QUICK SPECS
  • Type: 8 in midbass, sold as a pair
  • Power Handling: 150W RMS, 4 ohm
  • Mounting Depth: 58 mm, 183 mm cutout
  • Crossover: High-pass above 50 Hz, 24 dB/oct
Hurry! Only 2 left in stock.
Stereo Integrity TM8 8 inch midbass, front view of the cone and dust cap

Stereo Integrity TM8 | 8 Inch Midbass - Pair

Regular price $ 499.99
Sale price $ 499.99 Regular price
Unit price
Includes Shipping On orders to the lower 48
Full Warranty Factory Backed
Expert Support Real Installers
INSTALLER'S TAKE

The TM8 is the TM65's bigger brother and the headline is that it did not get deeper. 58 mm, essentially the same as the 6.5, for an 8 inch cone. The constraint here is the 183 mm cutout, not the depth, so measure the opening first.

The same door logic applies. Qts runs from 0.74 to 1.10 across the two measurement sets, deliberately high because SI built it for infinite baffle use in a door. In a door that is correct. In a small sealed box it will sound thick.

High pass above 50 Hz at 24 dB per octave. SI suggest crossing to a tweeter at 3,000 Hz for a 2 way and that matches what the on axis response actually does. Note this one is a single 4 ohm rather than dual, so a pair wires to 2 ohms or 8.

If you have the opening for it, an 8 inch midbass changes a front stage more than any tweeter upgrade will, and it is the first thing I steer people toward when they have the room. 90 dB sensitivity and 7.9 mm of travel means it keeps pace with a subwoofer instead of running out of room halfway through the handoff.

Product Details
Specifications
Enclosures
FAQs
Related Video
Product Details

Stereo Integrity

TM8

8 Inch Midbass | Sold as a Pair

Pure Aluminum Cone 50 mm Copper Voice Coil 7.9 mm One-Way Xmax 58 mm Mounting Depth 150W RMS

Big Midbass, Shallow Depth

The TM8 is a completely new, low distortion 8 inch driver that Stereo Integrity designed with Finite Element Analysis in North Carolina. It uses a custom tooled cast aluminum basket with an integrated rain shield and mounts in just 58 mm, so it can bring 8 inch midbass to locations that would not clear a deeper driver.

Its primary role is midbass in a vehicle door, and Stereo Integrity built it to deliver serious output there without giving up mounting depth or budget.

Engineering Highlights

Twin Shorting Rings

A copper pole sleeve and a magnet ID shorting ring lower and linearize inductance. Stereo Integrity says the resulting Xmax to Le ratio is usually found only in far more expensive drivers.

50 mm Copper Voice Coil

Solid copper windings on a CZA former drive the pure aluminum cone, and the three work together to move heat away from the coil for better thermal power handling.

Aluminum Cone, Rubber Surround

The pure aluminum cone is shaped for strength to weight and rides on a rubber surround and a Nomex spider for controlled, punchy midbass.

Door Tuned Qts

A door behaves much like an infinite baffle, so Stereo Integrity gave the TM8 a higher than average Qts, in the 0.8 region, for the best balance of extension and output in that space.

Crossover and System Integration

Stereo Integrity recommends a high-pass point above 50 Hz with a slope of 24 dB per octave or steeper. The TM8 covers 27 Hz to 7,000 Hz in a vehicle and extends to 4,500 Hz on axis, and Stereo Integrity recommends a 3,000 Hz crossover point in a 2-way system.

Build a front stage: For a 2-way, pair the TM8 directly with the M28 tweeter. For a 3-way, add the M3 Carbon midrange between them.

Enclosure Options

The TM8 is designed for infinite baffle use in a door, and Stereo Integrity also lists enclosure recommendations: 0.2 cubic feet sealed, up to a maximum of 1.5 cubic feet, or 3.0 cubic feet ported and tuned to 28 Hz with 7 square inches of port area, within a range of 2.5 to 3.5 cubic feet.

Fitment

Outer diameter: 209 mm. Cutout: 183 mm. Mounting depth: 58 mm. Flange thickness: 4.2 mm. Impedance: single 4 ohm. Sold as a pair.

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 plan a front stage around the TM8.

Specifications
Specifications
ModelTM8
Size8 in midbass, sold as a pair
ImpedanceSingle 4 ohm
Power Handling (RMS)150 W
Sensitivity90 dB
Voice Coil50 mm (2 in) solid copper on a CZA former
ConePure aluminum
SurroundRubber
SpiderNomex
MotorFerrite, copper pole sleeve and magnet ID shorting ring
BasketCustom tooled cast aluminum with integrated rain shield
TerminalsSpring push
Outer Diameter209 mm
Cutout183 mm
Mounting Depth58 mm
Flange Thickness4.2 mm
Listed Weight4 lb
Thiele-Small Parameters
ParameterKlippel Large+ColdSmall Signal
DC Resistance (Re)4.2 ohm3.79 ohm
Resonant Frequency (Fs)46.0 Hz67.4 Hz
Electrical Q (Qes)0.911.42
Mechanical Q (Qms)3.984.93
Total Q (Qts)0.741.10
Voice Coil Inductance (Le)0.26 mH0.26 mH
Effective Piston Area (Sd)35.16 sq in35.16 sq in
Equivalent Compliance (Vas)24.4 L12.57 L
Force Factor (Bl)6.89 Tm6.04 Tm
Moving Mass (Mms)35.4 g32.3 g
Suspension Compliance (Cms)337 um/N172 um/N
Linear Excursion (Xmax)7.9 mm one-way (70% Bl)7.9 mm one-way (70% Bl)
Mechanical Excursion (Xmech)11 mm one-way11 mm one-way
SPL89 dB89.6 dB
Response and Enclosure
Frequency Response25 Hz to 6,000 Hz
In-Vehicle Range27 Hz to 7,000 Hz
High-PassAbove 50 Hz, 24 dB per octave or steeper
2-Way Crossover Point3,000 Hz
Sealed0.2 cu ft (up to 1.5 cu ft)
Ported3.0 cu ft (2.5 to 3.5 cu ft) tuned to 28 Hz
Port Area7 sq in
Figures as published by Stereo Integrity. Large+Cold values are Klippel large-signal measurements; small signal values are the conventional set most modeling tools report.
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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