Systems ListFunk AudioFW21.0

ManufactureFunk Audio
System typeSealed
Number of drivers1
Internal volume3.5 ft3
External volume6.45 ft3
Dimentions (Width × Height × Depth)22.5 " × 22 " × 22.5 "
Weight110 lbs
Power4800 W


The Funk Audio FW21.0 is the big brother to the FW18.0 that was evaluated some time ago. In many ways they are similar. Both use compact Baltic Birch enclosures with curved sides and internal bracing. Both are available in a huge array of veneer finishes. Both are sealed systems powered by the ALL-DSP enabled Funk Audio M1 amplifier platform. The FW21.0 of course is a bit bolder and bigger than the FW18.0 in a number of ways. The cab is only marginally larger at 22.25x22.25x22”. The curved sides make the cab look even more compact than the dimensions suggest and in fact this is about as small as a cabinet could be for a large 21” driver while still fitting room for the amplifier and other hardware. It is a very compact system considering the amount of horsepower involved. The obvious difference from the FW18.0 is the TSAD21v2 21” driver. Like the other Funk Audio bass drivers this one also has a cast aluminum frame, large diameter 4.5” voice coil, 10” diameter spider, inverted aluminum dustcap and an NdFeb based motor, but the TSAD21v2 driver takes the motor to a different place than the TSAD18v1 driver in the FW18.0. The TSAD21v2 motor employs an array of large, high grade neodymium magnets outside of the coil rather than using an internal magnet arrangement in the pole. This is more expensive and wastes more magnet energy but results in higher flux in the gap. The result of the large amount of neo magnets and the large 4.5” diameter voice coil is a very high motor force factor for better efficiency. The motor also employs a large amount of aluminum in the two shorting rings to lower inductive distortion. The inductance is claimed to vary by only 10% over a stroke of 3” peak to peak. The top and back plate are machined steel that are chrome plated. The pole piece appears to be a separate 3rd piece of steel. Venting in the motor is substantial. There is no center pole vent but a series of 10 under gap vents in the back plate, venting between the magnets and the top of the pole has a rather involved looking amount of vents machined into it that appear to vent from the top of the pole to underneath the gap somewhere. Overall the motor looks like an artists interpretation of a UFO. A 4 layer 100% carbon fiber cone is also used on this high end driver. The other major step up that the FW21.0 has over the FW18.0 is not as readily apparent from just looking at it. Though the amplifiers look the same from the outside of the cabinet the FW21.0 has two 2400w rated M1 modules internally. Both are mounted to the same heatsink and run with one connected to each voice coil of the driver.

As I’ve come to expect from the Funk Audio subwoofers I was impressed with the parts quality and craftsmanship of the FW21.0. Even the packaging was above average. I tried out the FW21.0 in my main HT room for a few weeks and it impressed me with the amount of power it could put into the room from such a compact form. I was able to drive my room quite well and was especially strong with music and concert blu-rays. The measurements all back this up too as the FW21.0 has a big set of balls for such a compact system. The FW18.0 was already an impressive system for its size but the FW21.0 is quite a bit more potent still. Distortion is low, headroom is high and the system is well protected and will simply mute the amp briefly if over driven hard enough. This did happen a few times with the high output test signals but never occurred during the listening tests in my room. I did not review the on board ALL-DSP this time around since I had already done so with the FW18.0 but it is a powerful and capable signal shaping system. All in all this is an expensive system but it also offers just about as much headroom as one can expect from a cabinet this size and the build quality and flexibility to go with it. Well done.