MM-4 Loudspeakers and MS-8.1 Subwoofer
The RBH MM-4 satellite is the speaker
most likely to survive a two-story fall. Though only 7" high, its diecast-aluminum
enclosure and metal grille make it the toughest speaker on the block. It would make a
great cannonball. The MM-4 is best known, however, as part of RBHs esteemed Compact
Theater, available in 5.1- and 7.1-channel packages. For those living with two channels, a
pair of MM-4 satellites ($249/pr) can be arranged in a 2.1 package with the Compact
Theaters MS-8.1 subwoofer ($399 each). I did just that.
Just try testing the MM-4s toughness with a quick rap
upside its head. Hurts, doesnt it? Im not sure about the musical tastes at
Roger B. Hassings (RBH) corporate offices in Layton, Utah, but they do seem to like
heavy metal in their speakers. Wheres all the plastic, the fiberboard? Even the
speaker terminals are metal -- the big-lug, gold-plated kind. Its no fetish;
its science. The inertness of the metal construction reportedly makes the speakers
resistant to resonance and distortion.
According to RBH, the 4" aluminum driver also
minimizes distortion at low frequencies better than typical paper or plastic drivers.
Paired with a 1" silk-dome tweeter in a compact enclosure (7" tall, tapered
toward the peak, 5" wide, and 4" deep), it helps the tiny MM-4 play louder and
with greater dynamics than many other compact systems. But with only 4" drivers, the
MM-4 can reach down to only about 100Hz, and so is not easy to match with a subwoofer. At
such a high crossover, the sub must combine power with fluidity. Even then, it risks
diverting the listeners attention when it becomes too obvious where those
double-bass notes are coming from.
Though not encased in metal, the MS-8.1 subwoofer is built
for the job. It uses two 8" aluminum-cone drivers -- one front-firing, the other
down-firing -- with a 200W amplifier in a side-ported, medium-density-fiberboard cabinet
measuring 13" high, 11" wide, and almost 14" deep. Nothing about it looks
compromised: It has five-way binding posts (not cheap spring clips) for its speaker-level
connections, a variable crossover from 40Hz to 160Hz for line-level connections, variable
phase control, a 230V/115V switch, detachable power cord, dual inputs and outputs, and a
heatsink on the rear panel. And, at 35 pounds, its a hefty little package. It
impressed me even before it played a note.
The MM-4 and MS-8.1 were plucked from a 5.1-channel edition
of RBHs Compact Theater, where they were supplemented with a Marantz SR7000
audio/video receiver, the excellent Sony DVP-NS755V DVD/SACD player, and cables by
Straight Wire and Analysis Plus.
When it came time for two-channel evaluation, I moved the
RBHs into a system with the Antique Sound Labs AQ1003DT, a 30W vacuum-tube integrated
amplifier; a Rega Planet CD player with modified ART Di/O D/A converter; and the following
cables: Canare Star Quad with Neutrik RCA connectors, MIT Terminator 3, DH Labs D-75
digital cable, and Analysis Plus Oval 9 speaker wire. The two MM-4s were connected to the
MS-8.1 via line-level outputs. I compared them with the Axiom M2i speakers
and EP125 subwoofer.
If it were a living being, the MM-4 would be a freak of
nature. This tough nugget has an amazingly clean top end, plays louder without obvious
distortion than anything Ive heard for its size, and projects a warmish, embracing
midrange -- not your typical "home theater" speaker.
With nicely recorded female vocals, such as those of the
now ubiquitous Norah Jones on Come Away with Me [Blue Note 32088] (producer Craig
Street is a star-maker), the MM-4 sounded like real music -- not the coughing, hacking,
tinny concoctions of a teeny-weeny speaker tailored for movie soundtracks. That is to say,
it didnt sound overly bright, like a lot of what you hear in its price range.
The MM-4 was equally resilient with the more demanding,
more lo-fi growls of Shane MacGowan on "Aisling," from MacGowan and the
Popes The Snake [Warner Brothers 85421]. The MM-4 delivers this song with a
midrange authority and clarity I didnt expect from something so small.
Relinquishing bass is the logical compromise with a small
speaker, but the MM-4 gives up more than that -- its rated down to only 100Hz,
making it a challenge to find a subwoofer that does its job without extracting too much
information from the MM-4s lower-frequency region. The ear should not be able to
pick up the source of low frequencies in a subwoofer-satellite system. If, for example,
the crossover frequency is set too high, the sound becomes localized; instead of a
nondirectional signal, you might hear voices or instruments coming from the subs
direction. Thats ruinous. If the crossover is set too low, the MM-4 will give out
before the MS-8.1 steps in, leaving part of the frequency range unaccounted for.
A crossover setting of about 115-120Hz worked best with the
MM-4 and MS-8.1 in my room, but your space might require a different setting. This
crossover frequency produced a good blend, without the sub becoming directional. Bass
sounds on The Snake were authoritative and quick. Not many subs in the
MS-8.1s price class could pull off this feat with the MM-4. These speakers were
literally made for each other, and they sounded it.
I recommend that owners experiment with the crossover
frequency and volume control, then with the variable phase control. If youve never
owned a sub and dont know crossover from phase, RBHs manual wont help
much. Its not that instructive with respect to setting up the system. The
first-timer wont even know how to connect it to the rest of the system, whether by
speaker wire or by line-level interconnects. A good dealer will help in this regard, and
is highly recommended.
The MM-4 rules the squirt-speaker division, but concedes
too much in both size and performance to rule its price class. The $255/pr Axiom M2i
has a more authentic midrange, a far bigger soundstage, and sounds more well-rounded, even
if it plays no lower than a modest 60Hz. However, the MS-8.1 stands up to any sub in its
price class. In both substance (35 pounds, dual 8" aluminum drivers) and style
(substantive bass energy without one-note slurring), it overpowered Axioms
lightweight EP125 ($380 each).
The RBH Compact Theater remains my first choice for a
budget-priced home-theater setup. There, the MM-4 benefits from a center-channel and, with
the correct processing, the option of playing a CD (or SACD or DVD-Audio) in a
In a two-channel system that demands the smallest
satellites, the MM-4 makes a perfect companion in an apartment, small den, or even as a
multimedia speaker. It is a well-made, smartly designed speaker that, with the proper sub,
can rock around the clock.
Price of equipment reviewed