Product Review - Acurus ACT-3 Surround Processor/Preamplifier - November, 1998

Karl Suager


Acurus ACT-3 Front Panel

ACT-3 Surround Processor/Preamp

Dolby Pro-Logic, Dolby Digital, and DTS Decoding

20 Bit D/As and A/Ds

11 Digital Inputs (8 Coaxial, 3 Toslink), 4 Sets A/V inputs, 4 sets Audio-Only Inputs; Outputs Include 2 Center and 2 Subwoofer

RS-232 Port

Size: 5 1/2"H x 17"W x 13"D

Weight: 14 Pounds

MSRP: $1,799 USA

Mondial Designs, Ltd., 20 Livingstone Avenue,  Dobbs Ferry, New York 10522; Phone 914-693-8008; E-Mail [email protected]; Web

Acurus, a division of Mondial, aimed at the entry level market of "high end," started shipping the ACT-3 recently, a surround processor/preamplifier equipped with Dolby Pro Logic (DPL), Dolby Digital (DD - AC-3), and DTS decoding. The Audio/Video crowd has anticipated the release of the ACT-3 for some time now. Backorders still filling, I had some difficulty obtaining a product sample, but I would not be deterred from the mission JJ put forth, and yanked a string for a date with this mysterious black box.

All the hubbub elicits an interesting point though. Many other manufacturers have already placed similar gadgets on the market, racing to cash in on the craze for the latest available. Mondial, a rather conservative company in statement and design as well as product releases, chose to postpone the ACT-3's birth to the world, making revisions until they felt comfortable with reliability and compatability issues. Since one of the methods Mondial employs to achieve a high value/price ratio lies in long production runs, it becomes all that much more important to nail a design from the get go. In the end, the brainiacs settled on a 5.1 (of course) preamp with DPL, DD, DTS, a handful of generic DSP music modes for stereo material, and most importantly, upgradeable firmware and software.  Should any new format emerge, such as a 5.1 music format incorporating Meridian's Lossless Packing (MLP) data stream, the ACT-3 may incorporate the decoding. That in itself doesn't come off as unique. At least five or six processors I know of do that.  The fact that the ACT-3 clocks in under two Gs doesn't sacrifice much, if anything, in build quality, and "isn't made by a mass market manufacturer" distinguishes this critter.

Truth be told, despite us gearheads who slobber over the stoic 1/4" thick, anodized, brushed alluminum faceplates of our favorite specialty audio companies, those who cater more to the mainstream (mass market) have a very real advantage when it comes to producing the best raw performance for the dollar . . . if they decide to pursue the course. That aforementioned advantage is, of course, mass production. Because of the resources in place to satisfy the competive requirements of large scale production, the big guys can sell a $1,000 receiver with Dolby Digital for the same price that a specialty manufacturer can offer a separate preamp with the same or even less features. And, the receiver as a processor might even win out in terms of performance in addition to wearing a few extra gizmos. If a Dolby Digital processor/preamp for under a grand fits the shopping criteria, performance-wise, a mass market receiver wages the best bet.

Even if a specialized company should choose to stray near the territory of the big kids on the block, not many do for precisely that reason. The little companies, though a scrappy bunch, don't have the facilities or the financial clout to generate products in volume sufficient to set the cost per unit low enough. If they did, they still lack the advertising muscle to grab enough of the market to unload the necessary inventory. They may offer a better quality product in terms of build, but even after streamlining the manufacturing process, it still costs more.

Mondial accepted that fact, but chose to skirt the border with the Acurus ACT-3.  At $1,799 retail, it fills a nitch above the typical mass market stuff, yet ducks the $2,500-and-up benchmarks that typically swim gill to gill with the biggest fish around (such as the Yamaha DSP-A1, the B&K Ref 20, Lexicon DC-1, and Meridian 565.)  Plus, the ACT-3 brings a pedigree to the table. Acurus has previously earned accolades for their power amplifiers, as well as the predecessor of the ACT-3, the ACT-1.  Mondial's Aragon line fronts some heavies in the respective ranks as well.

The facade of the ACT-3 makes me think in some ways of a military school cadet.  Clean, yet stark, spiffed up but simple, functional but still lean to the point of avante garde, even perhaps attempting an elitist pose. Only a single knob and a handful of diminutive buttons decorate the face plate. Combined with the featured inputs, outputs, ports, and software, the ACT-3 looks dressed to seduce the custom installer as much as the typical A/V geek like myself.

Acurus ACT-3 Rear Panel

The rear panel sports a collection of inputs that allow eight total sources, each with their own analog and coaxial digital audio jacks. Four composite and two S-Video inputs, as well as three Toslink jacks feed the system, which then spits the typical 5.1 preamplifier outs (two center and two mono subwoofer outputs) as well as two pairs of analog audio outputs, two composite video outputs, and one S-Video output for purposes of recording and monitoring as the user sees fit. In addition, a RS-232 connection, an IR input port, and 5V trigger lend a lot of installation flexibility.

The custom software options, accessible only by simultaneously turning up the volume knob and powering on, allows separate On/Off IR commands for Xantecish IR repeaters serving automation systems, as well as an auto On/Off, and programmable input labels (including 8-Track). Get out the Bee Gees!

The setup procedure did feel a bit strange. Not bad, just different. Instead of directly accessing the individual parameters, the path took a roundabout way in order to make the process itself simpler. For instance, to set the parameters for a given playback mode (DPL, DD, DTS, etc.), the user must activate that mode through the auto switching feature by feeding software of the specific format, and then enter the programming menu and set delay times, levels, bass management, or whatever. And, in cases like bass management, one can't directly control the state of the 5.1 speakers, but rather choose from five preset configurations available, none of which will not allow the main left and right channels to share the LFE channel with the subwoofer output, nor can the sub level be set with test tone calibration, but must find its groove during listening with program material. Also, even though a configuration exists for five full-range speakers, as well as full-range main and rear speakers, it isn't possible to allow full-range operation of the left, center, and right channels while limiting bass content to the rear. Granted, that's an unlikely scenario, but in situations with perforated screens, it's plausible to have small rear speakers mounted on the side walls with three matching full-range speakers in the front   All of these issues may be addressed through external hookup rigging, but it's still a departure from the more common setup procedure that allows more direct access.

Once the parameters are set for each mode, they remain as a separate default for each, even when a user adjusts levels to compensate for personal taste with particular program material. Although the setup does diverge from the conventional, it also makes it difficult for the non-techno-inclined to get things really out of whack. Select the source, press play on that source, adjust your volume, and away you go. This in itself will save many users, salesman, and installers the frustration, time, and expense of unnecessary service calls. If you're a hobbyist in the A/V arena, you might wonder how difficult a time a person could have watching a movie through their stereo.  If so, you might be shocked. I've seen customers walk into a store, steaming mad, convinced that a receiver was defective only because they thought the effort to open the manual to the trouble-shooting section and follow the suggestion to press the "Tape Monitor" button too inconvenient.

Acurus ACT-3 Remote Control The programmable IR remote operates most major brands of equipment, but cannot learn IR commands from other sources. I found codes to operate the basic functions of my own stuff, but couldn't get a code to operate an ancient RCA television perched in my parents' entertainment center. Four Macro buttons allow up to eight steps of the programmed commands. A fully learnable remote with more IR codes, or at least a more documented brand listing in the manual would have offered a more complete package, but the ACT-3's price requires a lean budget, and anyone can spend another $139 on a remote which will do just that.

Here it comes, the place for statements of drama and astonishment, classically reserved for a writer to exchange hyperbole for fame by means of an advertisement quote in some glossy rag. Keep waiting dudes. If you want glossy, polish your screen. We began the engagement with a two-channel shootout between the level-matched (within 0.5 dB) output of the ACT-3 and the older but excellent JVC XLZ-1050 CD Player which I also used as a transport to test the DACs in the ACT-3, compared to the DACs in the player itself. Switching between the two with a passive controller, I did this test primarily to evaluate the performance of the ACT-3's onboard DACs and analog output stages by themselves, reasoning that they would ultimately become the limiting factor in any surround mode. Except for proprietary DSP processing on some models, Dolby Digital and DTS decoding chips are primarily routing data.  Stereo, by its limited nature, can show subtleties in the chain of reproduction to a flawed extent. What 5.1 recordings can potentially do by brute force, stereo must accomplish by nuanced trickery. Besides, even though I believe that more than two channels are necessary to significantly advance the state of the art of music reproduction, 5.1 recording in general hasn't standardized, let alone matured. Currently, 5.1 mixes reside primarily in the realm of cinema, a world that often seems oblivious to the virtues of fidelity.

With most recordings of average quality, the difference between the ACT-3 and the JVC was slight or nil. The most revealing turns came with material such as Mars Lasar's "Eleventh Hour". With Q-sound and Head Related Transfer Function techniques, the music can either immerse the listener in an ocean of dimension, or simply shimmer some sounds around the old bean. Using the JVC as the analog source, I could only sink a smile into the sheer ridiculous but convincing unbelievability - thunderstorms, wolves, and little infant girls dance though my mind to the cadence of some mad magician. Using the ACT-3 essentially as an outboard DAC, all the performers showed up, but couldn't make me shudder. Bass still had good presence. Midrange and treble avoided any irritating hash, but couldn't open up the miracle I have come to lust after. To be fair, the ACT-3 isn't an outboard dedicated two-channel DAC, and I haven't heard a surround processor that could function well as one until they move over that $2,500 mark, but hey, I can hope can't I?

A variety of movies in Pro Logic and Dolby Digital slammed through the ACT-3. The Dolby Digital soundtrack of "Toy Story" wrapped me up with little Maggie (my daughter) on the lap - a father and daughter enjoying the sweet spot while mom had to sit to the side. Throughout our "moony" session, the ACT-3 followed instructions to the T, allowing our enjoyment to jump along without impairment. DTS music discs such as Alan Parson's "On Air" alluded to the impressive possibilites of 5.1 music recordings, but didn't quite knock me on my tail. All in all, the processing surpassed the older Yamaha DDP-1 DD Decoder, and pulled in closely to the Millenium 5.1 DTS Decoder, though the differences each way weren't vast. Considering that a good Dolby Digital receiver and an outboard DTS decoder such as the Millenium would run about the same as the ACT-3, that's actually pretty good. The ACT-3's built-in digital surround decoding modes DD and DTS) mean less cable, less space, and a more attractive, more solidly built product. Should internal amps and extra features like tone controls add value for the prospective purchaser, the receiver combo becomes more attractive.  However, if somebody doesn't want non-critical controls or internal amplifiers, the ACT-3 acquires top billing.

Though features tend to take a back seat in "high-end" applications, many of them do come in handy. Personally, I would have liked the option of stereo subwoofer outs such as those on the Yamaha DSP-A1, perhaps presets, and adjustable subwoofer crossover with a variety of slopes and crossover points to choose from. A digital five-band adjustable parametric EQ wouldn't hurt either. Still, I can't expect a beverage to taste like good Scotch but have the price tag of a 40 oz. bottle of King Cobra. Nothing can be everything to everyone. Any attempt to do so always leads to failure in more respects, and at under $2,000 for a product like the ACT-3, such compromise would be suicidal.  Acurus left the gizmos off to keep the costs down and build quality up, and the build quality is really something. It's not of the same caliber as Mondial's own Aragon line, Krell's KAV products, or the beautifully sculpted Balanced Audio Technology gear in terms of finish, but the chassis does resist flexing remarkably well, exuding a solid and trustworthy feel to the touch. With quality of this kind, one may often take a bit of pride, and a sliver of satisfaction during operation. There is value in the tactile experience of audio equipment. It is, after all, the whole experience that shapes the curvature of the lips at the end of the bout.

Now before anyone goes running out with a checkbook flapping from the pocket, be aware of a couple quirks that we should address:

  • Since the processor controls each channel's analog volume control digitally, with 70 discrete steps, at very quiet listening levels, the user can't adjust the front-to-back and left-to-right levels very far before losing all sound on one side, because the processor can't turn the levels down any more without muting them, which it does. This fact isn't crippling, but a little annoying if you're trying to listen to surround material late at night with a kiddy in a nearby bed. No one I know has ever listened to movies that low, so for typical situations it probably won't ever arise.
  • The noise floor of the ACT-3 is substantial, both electronically in the form of a background hiss, and mechanically through transformer hum. The effects in use will depend not only on the ambient noise levels in your listening room, but the gain/sensitivity of your amp/speaker combination. The electronic noise is constant regardless of volume up to unity (gain =1), which would overload most amplifiers, and then increases when the volume is set above that. Level controls available with some amps can alleviate the problem, maximizing the S/N ratio between the preamp output and amplifier intput.  With my Aragon 8008BB, which has a voltage gain of 28 dB, and Infinitys which have a voltage sensitivity of 87dB/2.83 volts/1 meter, I could hear the electronic noise two meters away. Farther than that, the electronic noise became lost underneath the slight mechanical hum of the ACT-3's transformer. Since I sit about 3 meters away, hiss from the front wasn't much of an issue. With a Sunfire amp (the two channel, 300 w/ch version) though, driving M&K satellites to the rear, about two meters away from my head, I could hear noise in the rear channels during low-level playback, which did bug me a little. It didn't bother me enough to construct attenuator pads for the rear channel amp inputs, which would have lessened the effect substantially. To put it in context, a computer in the same room would mask all of the above. The only time that this might become a really serious issue is with very sensitive speakers placed very close to listeners in a quiet room at low listening levels. Otherwise, the noise you don't want to hear will get lost in the noise you do.


The Acurus ACT-3 has stacks of competition from above and below in terms of price. In my opinion, it will appeal mostly to those who don't want to play with their food, but simply eat it. The ACT-3 is a set, forget, and romp style brick.  It looks pretty nice, sounds pretty nice, and is difficult to screw up.  Couple that to the upgradeable architecture and price tag, I'd venture to say it's a fair deal.

Karl Suager

Associated Components used for the review:

Infinity Renaissance 90 Loudspeakers
Aragon 8008BB Power Amplifier
Passive controller w/50 k Nobel Pot
JVC XL-Z1050 CD player
Yamaha DDP-1 Dolby Digital Decoder
Millenium DTS Decoder
DH Labs Silver Sonic Interconnects & Speaker Cable
Liberty CL-3 rated 14-4 Speaker Cable
Bybee/Curl Power Purifiers and Power Cords
API Power Pack V AC Line Conditioner

© Copyright 1998 Secrets of Home Theater & High Fidelity
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