Technotes Online > Alesis ProLinear 720 DSP Active Monitors

Alesis ProLinear 720 DSP Active Monitors

Issue #10
February 04, 2004
Alesis ProLinear
720 DSP Active Monitors

Custom DSP technology creates a powered monitor that's somewhat of a sonic chameleon!

When I heard that Alesis was set to release a new set of active monitors with onboard sound-shaping DSP, I naturally requested a pair for review. Let me state right up front that the company has really been great about getting whatever products I request into my hands, which is why you've been seeing so many of their products reviewed here in my column (besides which, they're so cool).

Actually, my relationship with Alesis dates back to the early 1990s when I created some sample sets for what was to eventually become the QuadraSynth, the first synth ever with 64-voice polyphony. More recently, the company, which had a long history of producing many firsts (think ADAT!) hit a rough spot, but they have bounced back with a vengeance, turning out a plethora of exciting new products like the Ion, the ModFX modules and three GuitarFX boxes that I'll be reviewing in a future column.

But let's talk about the monitors, because this is a really exciting new product for the company. First off, the ProLinear 720 DSP lists for just $450 per speaker, a figure that just a few years back would have been unheard of for an active monitor, not to mention one that has onboard digital signal processing power!

The listening tests.
The first point I want to make is that these monitors sound way better than I ever expected them to, considering the fact that your Sweetwater price for a pair of ProLinear 720s will be about $700 and change, which is clearly a bargain. The 720s are rated at 80 watts for the 7-inch Kevlar woofer and 40 watts for the silk dome tweeter, though the dynamic power for peak transients will easily exceed these numbers.

While I wouldn't particularly call these accurate monitors (few speakers that you or I can normally afford would be), they do offer high quality sound at a truly affordable price. Compared to my old monitors, the 720s sound very clean, rich and finely-detailed. You can listen to them a long time without suffering from the dreaded "speaker fatigue."

Augmenting the low end, there are two slim ports on either side of the tweeter housing, and when played at normal room levels, there's a lot of air moving through them, so you know the bass will be solid, and while the frequency response is given as 50Hz to 20kHz, the woofer's response is only 3dB down at 43Hz, right about the frequency of a low E string on a bass guitar (which is actually 42Hz if you want to get picky).

In my listening tests, the ProLinear 720s actually fared better when placed out farther into the room than I would normally set a monitor. In fact, with the 720s set about three feet out and at least three feet away from any adjoining walls, they sound very "cinematic." By that I mean the stereo soundfield (left-to-right) seems quite expansive, so that some sounds seem to come from far to the right or left of each speaker's position in the room. This is pretty impressive already, but once I tweaked the user presets with the onboard DSP, I was also able to literally shake the room with some recordings with extremely low bass - indeed, so much so that the average person would start looking for the subwoofer!

One of the very best test recordings for low bass is the Telarc digital recording of Saint-Saens' Symphony No. 3 (best known as the "Organ Symphony") by Eugene Ormandy conducting the Philadelphia Orchestra with Michael Murray playing the great organ at the St. Francis de Sales cathedral in Philadelphia.

This recording, done early on in the digital age - 1980! - still has the most prodigious pedal tones of any performance in my collection. By adding just 3dB of bass response at 31.5Hz the ProLinear 720s were able to reproduce all but the very lowest notes on the organ's pedalboard, some of which actually dip below 20Hz! And I'm talking about monstrous bass, not just bass that is audible; you can also feel those low notes, particularly when I moved the monitors into the master bedroom, which is so large, I actually have plenty of space to set up gear at one end.

Likewise, several SACD and DVD-audio recordings (which we'll be discussing in my next column on high resolution audio) came through the 720s with astonishing depth and clarity. For most normal studios that don't have a "sky's the limit" budget, the ProLinear 720s are a lot of speaker for the asking price. I sincerely doubt that anyone who hooks up a pair of these babies will have any complaints.

Now, having said that, I do confess that my own home studio suffers from a serious problem with bass response, and even with a high-powered subwoofer that's clean down to about 30Hz, you are never going to be blown away by the bass (I plan on reconfiguring the studio very soon and adding some Auralex foam baffles and corner fills). But out in my home theater (what normal people would call the living room) and particularly in the master bedroom, the 720s were very impressive.

DSP on a speaker system?
Now here's where you'll really appreciate what the ProLinear 720's onboard DSP can accomplish. First off, the 720s ship with eight factory presets and eight user presets. Preset number one is essentially flat across the full frequency response. Honestly, I cannot imagine many users choosing this preset, though it might be okay in certain rooms with a subwoofer or when using the 720s as nearfield monitors.

Preset two has a pleasant traditional "hi-fi" response that's based on the classic Fletcher Munson curve, with a bit of additional presence in the high end and some bass boost at both 20 and 50Hz. Meanwhile, preset three features a very good representation of the classic "white cone" monitors that almost every studio keeps on hand for its detailed high end (some find it too detailed, to the point of sounding shrill when compared to most other speakers).

The preset I favored is number four, which Alesis calls the "Faux Finnish," a clever play on words to describe this model of a famous near-field monitor from Finland. Preset five is called "Studio Cube," which is a very good recreation of those "worst case mix check" brown speakers. Other presets include everything from "Boom Box" to "BBC Dip" which has a slightly warmer top end.

While it's fun to listen to music through the various presets, you can also use the onboard DSP to help compensate for various listening room anomalies. I created what I thought was a very good preset for my specific studio and saved it to user preset two, while moving the flat response to user preset one, and "Faux Finnish" to user preset three. Now I could mix, then audition the final product through all three presets, which would give me a good sense of what most other people would likely hear on their particular system. You could also add the "Studio Cube" as a final mix check.

Psst . . . Got a PC handy?
Alesis includes a CD-ROM with each ProLinear 720 that has Windows-based software (for Windows 95, 98, ME, XP and 2000), so you can program your response curves graphically, right on your PC. And they thoughtfully include a standard 9-pin PC serial cable in case you don"t happen to have one close at hand. Mac users will have to work the DSP from the onboard display, but once you get a handle on what button-pushes do what, it's a breeze to navigate.

While the ProLinear 720s probably won't find their way into many pro-level installations, I think most Sweetwater customers will find this is a great value, particularly thanks to the onboard DSP. In comparing the ProLinears to my existing home theater speakers (which are $1,000 each Infinity towers), I felt that the 720s more than held their own. The limiting factor (at least in my room) is that the 720s won't play loud enough on their own. Big explosions or other fast, low frequency transients tend to overdrive the 720s a bit short of volume levels I would normally run my system at. However, by switching the bass management system on my Yamaha 5.1 amplifier to send all the information below 100Hz to my monster subwoofer, I had no problem cranking everything up to and beyond comfortable listening levels.

Oh, one last point: As is the fashion these days, the 720s ship without any protection or covering on the drivers, so they look great, but be careful when you reach into the box - you don't want to put a finger through the tweeter.

Okay, so you have a powered monitor with onboard DSP that can essentially be used to "model" other speaker systems. And you can take home a pair of these babies for about $700 and change. To me, that's a real bargain. At this price, you certainly won't find any set of speakers that will sound better or that have the versatility of the Prolinear 720s. If you've been considering an affordable upgrade in your own studio (or a 5.1 setup), I promise you that the Alesis ProLinear 720 DSPs will not disappoint!

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