Ascendo The18 SUB PRO

The18 SUB PRO is the shallow subwoofer, and the dimensions are the argument: 48 inches high, 24 wide, and only 11 deep. A conventional subwoofer of this capability is a cube that has to be accommodated. This one goes into a soffit, a riser or a stage front and effectively disappears.

Getting there took a neodymium motor in place of conventional ceramic magnets, with a four-inch ultra-high-temperature voice coil, which is what allows 137 dB at 100 Hz out of a cabinet that shallow. Where a room needs more, Ascendo builds the same enclosure with two 18-inch woofers stacked — The18-2 SUB PRO Passive Sealed SH — reaching 143 dB from a cabinet that is, if anything, marginally slimmer.

It is a passive design, so Ascendo amplification and DSP sit behind it. Like the rest of the PRO subwoofers it is engineered to stay in phase with the infrasonic models above it, which is what makes it possible to run audible bass and sub-20 Hz content together without the two fighting each other.