Rocket ULW-10 Features
I have noticed a paradoxical trend in the marketplace for audio products, the past few years. There are some manufacturers, who mechanically repeat their churn of new products and occasionally slide up their prices for no significant improvement in product (not that their claims will ever admit that). On the other hand, I see products like this and when I look at the features, I am floored. I am honestly mystified as to how AV123.com can afford to offer these features at this price point. Let me furnish you the details, and you can judge for yourself.
The review sample was finished in white shadow maple, and to as high a standard of
fit-and-finish as I have seen. I have seen lesser finishes for a lot more money. I will begrudgingly
admit this piece is better finished than both my current reference units. To help you not mar the
veneer, they have thoughtfully wrapped the unit in a cotton sock and included a pair of white cotton
gloves. Now, this can mean one of two things -
either, a disproportionate amount of resource has
been put into the appearance of this product and the performance will be compromised; or the
aesthetics, features and performance of this product are well balanced and the excellent finish
foreshadows a product of tremendous value. Let's find out.
The unit also comes supplied with a set of brass spiked feet, threaded to give you
adjustability for uneven floors. They did not stop there, they also included a set of brass discs to
rest the feet on in the event you want to place this on flooring that could be damaged by spikes. And
just in case you had a philosophical or aesthetic grievance against brass, they also included adhesive
backed rubber feet. It is nice to be pampered with these touches, but to experience it at an
entry-level price point is outstanding.
The rear panel features a single RCA jack for the LFE input. Obviously, this sub was designed with the assumption that it would mainly be used in systems with a receiver/processor sporting a sub-out feed. If you intend to use this with stereo pre-outs or speaker level feeds, then you will have to get the appropriate adapters in place. I would have preferred this unit supplied with stereo RCA inputs, an LFE input and speaker level inputs. I fed the sub either from the LFE out of my receiver, or a parallel feed from the speaker outputs of my integrated amp.
Next on the rear panel are the level, phase and crossover controls, each furnished with a
nice sized dial and adequately graduated markings. A small point it may be, but I feel strongly about
it from experience and Rocket has done well in this regard. Actually, I wish my reference ACI Force had
these dials. The phase control is continuously variable from 0 to 180 degrees, very nice at this price
point. The crossover is continuously variable from 40 to 120hz, and also had a bypass setting, which we
recommend when using the bass-management function of an upstream component.
The 10" anodized alloy woofer is driven by an 8 lbs magnet and a 350W built-in amplifier. And then, of course, there is the SOS...
And the Main Event
The hottest feature of this beauty is the SOS or "Subwoofer Optimization System". What does that mean in non-hype? Well - it is a one-band parametric equalizer, with the settings automatically established by the subwoofer.
Huh - what does that mean? The subwoofer comes supplied with a microphone and 20' chord. You plug the mic into the back of the sub, place the mic in your normal sitting location, at your seated ear level. Turn on the "calibrate" mode, and abra-cadabra - you have the audio equivalent of a rabbit pulled out of a hat.
When you turn on the "calibrate" mode the sub generates a series of tones and measures the overall response at the listening position, including the impact of the room. The SOS module picks the single largest peak and flattens it, relative to the rest of the curve. Brilliant! Executed correctly, this should result in the elimination of a boomy or resonant artifact, as it did in my listening tests below.
The owner's manual is well written for this setup, but here are some points I feel need to be mentioned or reinforced;
-
You room should be setup pretty much the way you normally use it during listening. The placement of furniture and doors/windows being open/closed could have a considerable impact on the room response.
-
Dial the crossover a little above where you expect to finally set it, before you engage calibration. My first try, resulted in a large hump at about 120hz, and the SOS did indeed flatten it. Alas, none of the speakers I have would need the sub to operate in that range, so the SOS was wasted and I still had a big hump at about 40hz.
I have to applaud the designers to not try and use "digital processing" as a gimmick to sell this unit, and in the process introduce a set of A/D and D/A conversions that can only pollute the source signal. While this sub does employ "digital processing" to perform the SOS calibration, the digital portion of the circuitry is turned off after calibration so as to not interfere with the analog signal. Brilliant!
