SM 28 – SpeedMount Two-Way Surface Mount Speakers with 8″ Woofer
Key Features
- Patented, concealed mounting system
- Includes 0° mounting plate and 10° mounting adapter
- Designed to accommodate division-of-labor installations and save costs
- 8″ (203 mm) long-throw woofer with dual tuned bass reflex ports
- 1.1″ (28 mm) silk dome tweeter
- Two versions available for low impedance or 70/100 volt systems:
– 8 ohm direct operation only
– 8 ohm direct and 70/100 volt operation
| SM 28, SM 28T | |||
| Audio/acoustic and electrical | |||
|---|---|---|---|
| Speaker type | 2-way, full range, indoor surface mount speaker | ||
| Frequency range | 59 Hz to 22 kHz, -10 dB, full space (per IEC 60268-5) | ||
| Frequency response | 67 Hz to 17.5 kHz, +/- 3 dB full space | ||
| Power capacity | 90 W (rms) continuous pink noise (per IEC 60268-5) 180 W (rms) continuous program | ||
| Rated maximum input voltage (MIV) | 25.1 V (78.9 W at 8 ohms) per AES2-2012) | ||
| Maximum SPL | 108 dB, 1 m (based on MIV) 109 dB, 1 m (linear) | ||
| Nominal sensitivity | 87 dB SPL, 1 W, 1 m, full space (per IEC 60268-5, 60 Hz to 20 kHz) | ||
| Nominal coverage angles | Horizontal: 105° (1 kHz – 4 kHz, weighted 2 kHz – 4 kHz) Vertical: 60° (1 kHz – 4 kHz, weighted 2 kHz – 4 kHz) | ||
| Nominal impedance | 8 ohms | ||
| Crossover frequency | 2.0 kHz | ||
| Rotary switch taps (SM 28T only) | 70 V: 64 W, 32 W, 16 W, 8 W, Off, 8 ohms direct 100 V: null, 64 W, 32 W, 16 W, Off, 8 ohms direct | ||
| Woofer | (1) 8″ (203.2 mm) polypropylene cone | ||
| Tweeter | (1) 1.1″ (28 mm) silk dome | ||
| Overload protection | Full range power limiter protecting the tweeter, woofer, and crossover | ||
| Input connectors | |||
| Speaker | 2 recessed pins (mate to receptacles on mounting plates) | ||
| Mounting plate | (1) Euro-style captive screw terminal block, 4 pole | ||
| General | |||
| Package | 2 speakers (1 pair) with mounting kit package | ||
| Ambient temperature/humidity | Storage: -40 to +158 °F (-40 to +70 °C) / 10% to 90%, noncondensing Operating: +32 to +122 °F (0 to +50 °C) / 10% to 90%, noncondensing | ||
| Mounting | Wall mountable with included mounting plates | ||
| 0° mounting plate | Fixed 0° | ||
| 10° mounting adapter | Fixed 10° up, down, left, or right, based on orientation of adapter | ||
| Yoke mount (optional) | Up to 90° upward/downward or left/right, in 10° steps based on orientation of yoke | ||
| Enclosure type | Plastic, trapezoidal, with molded grille and bass reflex ports | ||
| Enclosure outer dimensions | |||
| Speaker only | 16.50″ H x 11.50″ W x 7.28″ D (41.91 cm H x 29.21 cm W x 18.49 cm D) | ||
| With 0° mounting plate | 16.50″ H x 11.50″ W x 7.80″ D (41.91 cm H x 29.21 cm W x 19.81 cm D) | ||
| With 0° mounting plate attached to 10° mounting adapter | Orientation: vertical, angled 10° down 16.78″ H x 11.50″ W x 10.16″ D (42.63 cm H x 29.21 cm W x 25.81 cm D) | ||
| Product weight | |||
| SM 28 | |||
| Speaker only | 10.1 lbs (4.6 kg) each | ||
| With 0° mounting plate | 10.9 lbs (5.0 kg) each | ||
| SM 28T | |||
| Speaker only | 12.0 lbs (5.4 kg) each | ||
| With 0° mounting plate | 12.8 lbs (5.8 kg) each | ||
| Shipping weight | |||
| SM 28 | Pair: 30 lbs (14 kg) with mounting kit package | ||
| SM 28T | Pair: 33 lbs (15 kg) with mounting kit package | ||
| Regulatory compliance | |||
| Safety/EMI | CE | ||
| Environmental | Complies with the appropriate requirements of RoHS and WEEE. | ||
| Product warranty | 5 years parts and labor | ||
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The Extron SM 28 SpeedMount® Surface Mount Speaker is a two-way speaker with a patented, concealed wall mounting system. It features an 8" (203 mm) woofer with dual tuned ports and a 1.1" (28 mm) tweeter. The SM 28 provides a frequency range from 59 Hz to 22 kHz, and a power rating of 90 watts continuous pink noise, 180 watts continuous program capacity. The Extron-exclusive mounting system is designed to accommodate division-of-labor installations and save costs. The SM 28 is available as an 8 ohm model, and an SM 28T version which can operate in 8 ohm direct as well as 70 volt and 100 volt modes. The SM 28T features a six-position power tap selector for up to 64 watts, which can conveniently be accessed through the grille from outside the speaker.
The innovative mounting system allows the SM 28 to slide onto the mount and lock into place. In the same installation step, the integrated electrical contacts on the speaker automatically mate with the pre‑wired contacts on the mounting plate to speed up and simplify installation. A release on the speaker baffle allows for quick removal from the mount. The release is lockable and hidden, and together with the concealed speaker wiring contacts, helps to deter theft.
To meet a variety of installation needs, the extremely flexible mounting system includes a 0° mounting plate and a 10° mounting adapter. The 0° mounting plate provides the electrical connections and allows the SM 28 to be oriented vertically or horizontally, flush with the wall. When the versatile 10° mounting adapter is added to the mounting plate, the SM 28 can be positioned with a 10° tilt downward, upward, left, or right.
The SM 28 saves time and installation costs for AV system contractors working with low-voltage contractors in a division-of-labor installation. During rough‑in, a low‑voltage contractor installs the mounting system on the wall and terminates the speaker cable to the mount's integrated wiring contacts. Later, the AV system contractor completes the installation by sliding the SM 28 onto the mount.
A pivot mount is available as an optional accessory for the SM 28. It allows for 360° of speaker rotation for maximum flexibility in aiming speakers. Pivot mounts are available in black or white to match the SM 28 speaker.
A Yoke Mount is available as an optional accessory for the SM 28. It allows for vertical or horizontal speaker mounting on a wall, or on a ceiling, with 180° of pivot available in 10° detented steps. The detents allow a consistent pivot angle to be set for multiple speakers. Yoke Mounts are available in black or white to match the SM 28 speaker.
The SM 28 speaker is ideally suited for classrooms, conference rooms, exercise facilities, retail spaces, auditoriums, spaces with raised or exposed ceilings, and other environments where surface mount speakers are desired. It provides accurate voice and detailed music reproduction for a variety of sound reinforcement applications.
The SM 28 is sold in pairs and is available in a black or white finish. It includes a 0° mounting plate and a 10° mounting adapter, and a 5 year parts and labor warranty.
Features
- Patented, concealed mounting system — One installation step connects the speaker to the wiring contacts, and secures it into place.
- Includes 0° mounting plate and 10° mounting adapter — Four position 10° mounting adapter attaches to 0° mounting plate, and provides flexibility for vertical or horizontal speaker installation with 10° of tilt downward, upward, left, or right.
- Designed to accommodate division-of-labor installations and save costs
- 8" (203 mm) long-throw woofer with dual tuned bass reflex ports
- 1.1" (28 mm) silk dome tweeter
- Two versions available for low impedance or 70/100 volt systems:
- 8 ohm direct operation only
- 8 ohm direct and 70/100 volt operation - Convenient six-position, through-the-grille power tap selector on the SM 28T:
- 8 ohm direct
- 70 volt: 64, 32, 16, 8 watt, and Off selectable
- 100 volt: null, 64, 32, 16 watt, and Off selectable
- Optional pivot mount allows for 360° of speaker rotation. Part # 70-978-02 and 70-978-03
- Optional Yoke Mount allows 180° of speaker pivot in 10° detented steps, part #70‑994‑02 and 70‑994‑03
- Frequency range: 59 Hz to 22 kHz
- 90 watts continuous pink noise
180 watts continuous program - Internal driver overload protection
- Hidden locking speaker release mechanism
- Mounting plate provides cable raceway access for surface-mounted wiring applications
- Black or white high-impact enclosure
- Dimensions with 0° mounting plate: 16.5" H x 11.5" W x 7.8" D (41.91 cm H x 29.21 cm W x 19.81 cm D)
- 5 year parts and labor warranty




