THE28 Sub Squared Pro Passive Sealed Shallow
Ascendo THE28 Sub Squared Pro Passive Sealed Shallow Subwoofer
ASCENDO THE28 Squared PRO uses dual front-firing and rear-firing 14" drivers (equivalent 28" displacement) in a passive sealed shallow enclosure for infrasonic bass extension in premium home cinemas.
Overview
The ASCENDO THE28 Sub Squared Pro Passive Sealed Shallow employs a push-pull dual 14" driver configuration — one front-firing and one rear-firing — in a sealed shallow enclosure. This push-pull arrangement cancels even-order harmonic distortion between the two opposing drivers, resulting in cleaner, lower-distortion bass output. The combined effective displacement of the dual 14" drivers is equivalent to a 28" single driver, enabling infrasonic extension and very high output levels from an enclosure depth suited to screen wall and riser integration. The sealed enclosure delivers the precise, controlled transient performance expected in reference cinema applications. As a passive design, the THE28 Squared Pro is driven from an external high-power amplifier, giving system designers full control over amplification headroom and protection.
Downloads & Documentation
Pros & Cons
Strengths
- Push-pull driver arrangement cancels even-order distortion for exceptionally clean bass
- Equivalent 28" displacement from a shallow enclosure depth that fits screen walls and risers
- Sealed alignment delivers tight, accurate transient performance preferred in reference cinema
- Passive design allows amplifier selection to be optimised for the project
Limitations
- Push-pull configuration requires a bridged or stereo amplifier wired for opposing polarity — requires careful specification
- Passive design means amplifier must be separately sourced and installed
- Large displacement capability means a high-power amplifier is essential to realise full potential
Full Specifications
Transducers
Performance
Electrical
Physical
Integrating the Ascendo THE28 Sub Squared Pro in Flagship Cinema
Kolosseum specifies the THE28 Squared Pro in flagship cinema rooms where maximum displacement, infrasonic extension, and exceptionally low distortion are all requirements — and where the screen wall or riser architecture constrains available enclosure depth. The push-pull design gives measurably cleaner output, which we verify on measurement during commissioning.
Room Requirements
Best suited to large cinema rooms where infrasonic frequency reproduction is a design target. Structural engineering should account for the subwoofer mass and driver reaction forces in the mounting position.
Acoustic Considerations
Infrasonic capable subwoofers excite room modes at frequencies that are difficult to treat acoustically. Careful DSP management, multi-sub array design, and active room correction are all part of the Kolosseum commissioning approach for this class of subwoofer.
Frequently Asked Questions About the Ascendo THE28 Sub Squared Pro Passive Sealed Shallow Subwoofer.
A push-pull design places two drivers in the same enclosure facing opposite directions, wired with reversed polarity so both cones move in the same direction simultaneously. This cancels even-order harmonic distortion, resulting in significantly cleaner bass output at high excursion levels.
A high-power subwoofer amplifier with bridge capability is recommended to drive the push-pull configuration at its full potential. Kolosseum specifies amplifier pairing as part of the system design.
Both approaches provide significant displacement, but the THE28 Squared Pro push-pull design offers measurably lower distortion. The THE16 approach distributes subwoofer positions in the room, which can improve bass evenness. Kolosseum advises on the best approach for each specific room.
Yes. The displacement and sealed tuning allow extension into infrasonic territory. In-room response at those frequencies depends heavily on the room dimensions and DSP configuration. We measure and verify during commissioning.
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View Details →Ready to Design Your Cinema Around the THE28 Sub Squared Pro Passive Sealed Shallow?
Kolosseum is an independent design consultancy, not a retailer. We design the complete cinema experience and connect you with authorized dealers for purchase and professional installation.
Tell us about your room, your budget, and your vision. We will create a complete cinema design that integrates the Ascendo THE28 Sub Squared Pro Passive Sealed Shallow Subwoofer with the right screen, speakers, acoustics, and seating.