Big Bang Tiny Sub

I began researching compact subwoofers in October due to needing something very compact to fit into the decor of my new family room. I had considered and dismissed the Sunfire line of subwoofers as they were simply too pricey.

Enter the Definitive Supercube line of subs. I found some info on the Definitive Supercube subwoofers that were released this year and discovered that they were designed with the same principle elements as the Sunfire offerings. The Definitive Technology Supercubes use high powered class D (digital) power amplifiers with a single long throw active driver coupled to two passive radiators of the same size.

A smaller speaker in a smaller cabinet can displace a lot of air if the driver moves a great distance (hence the term "long throw") and is fed by a very powerful amplifier. The class "D" digital amplifier with it's very high power output capability is a relatively new technology and is just now starting to trickle into subwoofer design resulting in smaller enclosures.

Definitive makes several models of the Supercube, ranging from the slighty large $1500 "Reference" Supercube down to the relatively tiny, inexpensive Supercube III.

Because we wanted the subwoofer to be virtually invisible in our very open family room we opted to purchase the tiny Supercube III. I fortunately had a contact at a local dealer who sold it to me for only $520 and left the door open to bring it back in if I wasn't happy with the performance.

Cosmetics
The thing that you immediately notice upon unboxing the Supercube III is how compact it is. Measuring just 10.5" cubed this sub is truly diminutive and can easily be tucked beside a sofa (even one close to the wall) or even behind an audio rack (more on that below).

The fit and finish of the Definitive product is (as always) top notch. The top of the unit is finished in a glossy painted piano black color that should fit easily into any decor. The sides of the sub have a stretched black fabric that gives it a sense of form over function that should make even picky decorators happy.

This little guy weighs a surprising 38 lbs! The sub is built with a high density material that is denser than MDF. This leads to a stiff heavy enclosure that should minimize vibration and prevent the unit from jumping around too much.

The unit includes two options for floor attachment; one set of screw-in spikes and a set of screw-in rubber capped feet.

Inputs and outputs are exactly what you would expect in a higher end audio subwoofer. High and low level inputs are included which will allow the sub to be fed from a dedicated subwoofer output or connected in-line to a set of speaker lines. Generally speaking the low level input is preferred due to lower distortion and the ability to use the higher quality low-pass filtered crossover control to set the sub crossover frequency.

The controls for the unit consist of 3 dials which control gain (volume) crossover frequency (the frequency at which the subwoofer begins to operate) and phase adjustment (puts the sub in or out of phase with the input audio signal). A manual is included which provides reasonable instruction on system setup options and the use of the controls.

System setup
Initially when setting up the subwoofer I tried for placement along the wall in the middle of my family room with the steel spikes mounted to the subwoofer. Although generally subwoofer placement is not critical, I was hoping that by putting the sub close to the listening area the sub's impact would be more noticeable.

The results of this configuration were abysmal. The subwoofer sounded very anemic and turning up the volume control only resulted in the unit beginning to distort and actually vibrate against the hardwood floor.

I was close to boxing it up and returning it but decided to see if there was any possibility that the tiny unit could be placed behind one of my main speakers in the entertainment nook built into one wall of the room. This would "corner load" the unit and might improve performance (subwoofer performance and impact is often augmented for better or for worse by placing it in the corner of the room, in essence the whole room becomes a speaker).

Testing
Surprisingly enough the tiny 10.5" unit just fit into the space provided. I swapped the steel spikes for the rubber mounted feet and re-connected all of the cables. I was very pleasantly surprised with the results. The first source I used to demo the sub in this placement was "Star Wars Episode II: Attack of the Clones". I used the opening scene in which a large spaceship rumbles by and then later explodes. The Supercube III delighted my fiancee, as you could now feel the rumble of the ship and hear the low bass tones that my full sized speakers failed to produce in the movie soundtrack. While the performance was not up to par with my SVS PCI 20-29 this was coming from a tiny 10.5" cube tucked into the corner of the room! I did discover that the 650 watt D channel amplifier could easily be overdriven.. in the scene in which the spaceship explodes if the volume was set too high the subwoofer amplifier would simply shut itself off for a few seconds.... there was no evidence of clipping before this shutoff occurred. I'm not sure if this was just a glitch in a certain frequency contained in this one sequence as I had played the sub louder in other sections without problem.

One thing that was very nice about the bass performance of this subwoofer was it's ability to switch frequencies very rapidly. There were no "aftershocks" or mushy harshness in the reproduction of the lowest frequencies. When the soundtrack had moved on, so had the subwoofer.

The sub might be a little too tight because a few frequencies resulted in a bit of "farting" in which very short bass notes were clipped off a bit early by the Supercube.

The next material that I used to audition the subwoofer was the DTS 6.1 soundtrack from "The Lord of the Rings - The Fellowship of The Ring Special Edition". I used scene 13 in which the hobbits have their first run in with a Nazgul. With a high powered subwoofer there will be a definite crunch as the Nazgul's feet hit the ground and also when it puts its mailed fist on the tree trunk. There should then be a very noticeable dull bass thump as Frodo feels compelled to put the ring on his finger. The Definitive performed very well considering it's size, only failing to produce a real "thump" from the impact of the hand on the tree.

The last demo I did with the Supercube III was in playing the Black Eyed Peas "Monkey Business" album. The subwoofer let me down a bit here as it was not able to resolve good detail in this hip-hop album when working on the lowest frequencies, it had a tendancy towards boominess or peakiness and I had to turn it's volume down to blend it with my main speakers. Performance was still decent and it will still augment full sized speakers in this application.

All in all I can definitely recommend this product if the primary requirements are 1) tiny size and 2) theater applications. I don't know of any other subwoofer with such tiny dimensions that can still fill out the subwoofer channel for movies without having to turn a room over to the dimensions of a massive sub. It probably won't fill the bill for bassheads who want room shaking detailed bass, but they will probably be looking at products that are 8-10X the size of the diminutive Supercube III.