The The24 SUB PRO ACTIVE SEALED infrasub is a statement.
Its huge cone surface area and huge 90 mm of linear stroke - represents a world record for cinema subwoofers - allow it to move a gigantic volume of 10 liters of air per stroke to pressurize the room. Due to its ultra-low resonance frequency and its sealed enclosure design the group delay is several times faster than the smaller 18", 15" or 12" subwoofers at the same frequency. Also the acoustic power output per cubic inch is by far in favour of this unique design compared to stacked multiple smaller subwoofers.
Its ingenious design allows the The24 SUB PRO AS to produce frequencies in the infrasonic frequency range with authority, reaching down lower than subwoofers with a smaller diaphragm surface ever will. At the same time this infrasub renders those notes with much more power, structure and resolution. This ASCENDO-developed 62 cm / 24" super woofer is powered by one of the best high current amplifier designs delivering 6000 watts of power for multiple seconds. Its state-of-the-art DSP control allows to perfectly align the The24 SUB PRO AS to any existing setup by adjusting crossover, phase and ampliture pesponse.

The The24 SUB PRO AS ideally suits not only all types and sizes of cinemas, but also high-end stereo systems. Much of the spacial room information of the recording envirnment in a great audiophile recording is contained in the sub 30Hz audio band. You will hear more details in mid and high frequencies.

The24 SUB PRO AS - more bass pressure, depth, structure, attack, imaging equals more enjoyment.

Specifications (selection)

Speaker type

24" forward-firing woofer, with dual 6,5" voice coil


45 mm Xmax excursion each direction (90 mm linear), voice coil remaining in homogeneous magnetic field

Passive | Active

Active, built in DSP Amplifier



SPL (Peak / half space 2 pi)

Measurement Data
134 dB @40 Hz 
120 dB @20 Hz 
104 dB @10 Hz 

Frequency range

Measurement Data (without DSP)
28 Hz - 500 Hz /   -3 dB
20 Hz - 500 Hz / -15 dB"

Air volume displacement 

9,9 L / in comparison 18" standard cinema subwoofer 1,1 L

Directivity horizontal x vertical in Deg°


Output power

6.000 W

Power voltage range

85 V - 265 V

Input sensivity, balanced input impedance

2.7V (with gain 32dB), 10k

Damping factor (20-500 Hz @8Ω)

> 400


High Performance 96kHz/24 bits AD/DA converters, 64 bit double-precision 96kHz DSP process

Input IIR EQ section 

Gain, Mute, Phase inversion, Delay (up to 116ms, 40m), 10 EQ filters (Parametric, Shelving, LP, HP, BP, SB, AP)

Analog Input Amplifier

1 x XLR balanced

Power connector

Neutrik powerCON True 1 in-out

Automatic power off


Network Switch

2ports Ethernet switch for daisy chain


OCS software control


Internally braced birch ply and MDF


29,53 " | 750 mm


43,31 " | 1100 mm

Hight with feet 

44,29 " | 1125 mm

Depth without grill 

19,69 " | 500 mm

Depth with plug

19,69 " | 500 mm


268,96 lbs | 122 kg


Structural paint black

Custom colour options 

Piano lacquer, colour of choice, matt or other finishes upon request

Shape customization 

Upon request 


Floor standing with feet


Technical modifications subject to change without further notice