GETTING DOWN TO BASS-ICS
Like Godiva chocolates and quick trips to Amsterdam, the promise of deep bass tends to work as a powerful hedonistic lure that can trap even the most outwardly sensible of audiophiles. There was a time when I would preach that if we could simply ignore the bottom couple of octaves, getting terrific sound would suddenly become much easier. This, however, was in the days before big pounding home theater soundtracks––back when you could still get away with some little mini monitors, especially if your musical diet consisted primarily of Vivaldi flute concertos and early Joan Baez records.
 | Available at www.av123.com for $399, the R-DES offers four parametric bands of equalization and four separate memory settings. You can create settings that offer various levels of correction, or compensation for one or many seating positions. |
Nowadays, most of us want something with a lot more kick, which usually means resorting to the use of a separate subwoofer. Adding that much low bass can, however, become a bit of a double-edged sword, along with the newfound bottom-end bliss, we might also end up with a stack of room interaction problems. When you stick a sub in a corner, it will often produce an in-room response that is about as flat as Pamela Anderson stretched out on a beach towel. Bass has a nasty habit of exciting room resonances at certain frequencies causing huge response peaks, while other frequencies might cancel themselves out resulting in big dips or suck-outs.
Flattening things out can be tricky, and while careful positioning and the judicious use of a good equalizer will help, most basic EQs simply don’t have the level of control needed to do the job properly.
Enter the R-DES, a remarkably versatile EQ (available at www.av123.com) that has been designed exclusively to correct bass response. Going well beyond the typical box covered with an array of sliders that you push around until it “sounds right,” the R-DES is what is known as a four-band parametric equalizer, with a bit of a twist in that you set up and adjust it through a connection to your computer. Luckily, the computer is only needed during the setup period, and once you’ve entered your adjustments in one of the R-DES’ four internal memories, you no longer need to keep it connected.
At first glance, an EQ with only four control bands
might appear to offer less flexibility than the typical graphic EQ with dozens
of sliders, but closer examination will show that by letting you adjust both the
center frequency and steepness of the adjustment filter, a parametric EQ lets
you fine-tune the response in a way that no graphic EQ could ever come close to
achieving. Then, when you add in the R-DES’ low-pass crossover and high-pass
subsonic filter, the whole package becomes a truly versatile set of tools for
solving bass issues.
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All this flexibility is useless if you don’t know how to use it. Fortunately, Onix’ software is easy to use and somewhat educational, as well. Record your system’s response, make adjustments, and see the effect of those adjustments on screen. | |
Like Jessica Simpson driving a Lamborghini, all of this power might be wasted unless there was an easy way to figure out how to twist all of those (virtual) knobs. To sort this out, the R-DES comes with some tools to help you determine the adjustments you need to make. First, you examine your subwoofer’s in-room acoustic response by measuring its output at different frequencies. A disc that comes with the R-DES contains a series of test tones that you play through the sub, while measuring the response with a Radio Shack model 33-4050 sound pressure level meter (not included). At each frequency, you note the level and enter the results into your computer using a program called Onix Graph Paper. As you proceed, the Graph Paper program will draw a pretty (or not so pretty) picture of your sub’s in-room performance, which you can then use to create a correction curve for the equalizer. The Graph Paper program even has an adjustable compensation setting to correct for the weighted response of the Radio Shack meter.
Once you are done, you connect the R-DES to the computer and upload the correction curve into its EPROM memory. The R-DES can store up to four curves at a time, which you can then select between using a button on the face of the unit. This means that you can have different settings for action movies and orchestral music, or you could have a setting for one seating position and another that averages multiple positions.
What really blew me
away about the R-DES, is how the designers at Onix were able to take a fairly
arcane concept, parametric bass EQ, and develop an interface and setup procedure
that makes it pretty easy for most people to understand what’s going on. While
the adjustments are all done manually, there’s no shot-in-the-dark guesswork
involved. As you adjust the on-screen frequency, level controls, and slope of
the adjustment curve, or Q,you get a simultaneous graphic representation of
exactly what each change will do, and this effectively flattens what could have
been a steep learning curve.
In my own system, I have always lived with a
significant peak in the bass at 65 hertz, and over the years I have used a
combination of careful sub placement and some gentle EQ from my B&K
Reference preamp/processor to tame things. With the R-DES, I was able to
eliminate this problem, while noticeably smoothing out the response throughout
the bass frequencies. The effect is quite remarkable, making the transition from
the sub to the main speakers much harder to hear, while adding a healthy dose of
additional weight and impact. As I review different products, I often need to
interface my M&K MX-350 sub with all kinds of different speakers and
electronics, and I can see that the R-DES will make this task much easier to do
correctly.
As with all good things, there are limits to what the R-DES can
achieve. Don’t think that with just a few twists of the controls, the R-DES will
coax ruler-flat bass down to below 20 hertz out of an 8-inch sub. A good rule of
thumb is to try to stick with fixing problem areas, because while taming a nasty
response peak can be very effective, filling in a deep bass suck-out is nearly
impossible.
Powerful, extended bass that is also tuneful and seemingly fast
is the ultimate goal for many subwoofer designers. When you add a properly tuned
R-DES into the mix, getting there becomes a little easier. I’m hanging on to
mine.
RATING: EXCELLENT
Description: Onix Rocket R-DES Digital Equalization System
High Points: Powerful tool for fixing bass problems; well-developed interface; multiple curve storage
Low Points: No automated operation; requires PC and Radio Shack SPL meter for set up; no MAC support
Contact: AV123, 877.543.7500, www.av123.com
Price: $399 (direct)