The Beta 50s are a 3-way design, with one 1”
tweeter, one 5” midrange driver, and two 8” woofers, loaded in a bass-reflex
system with a port to the rear. As with all speakers using rear ports, give
them at least 6 inches or so away from the wall behind them. Otherwise, the
nearby boundaries might inadvertently change the reflex system's tuning
It is entirely possible that we might want them even farther into
the room for other acoustic reasons anyway, but consider that distance a
minimum, particularly if the speakers are running ‘full-range' to a
substantial degree, i.e., not benefiting from bass management.
The Beta 50 towers are rated to 35 Hz –3 dB, 30 Hz – 6 dB. Loudspeaker specs
provided by manufacturers are probably the numbers I take least seriously,
as low frequency extension, or for that matter the speaker's in-room
response, will vary considerably with the specifics of placement and
acoustics. Still, 35 Hz can provide some satisfying bottom end, almost what
you could call a ‘full-range' loudspeaker, but you bass aficionados will not
be assuaged, and will want a subwoofer to handle that last octave, if not
the bottom two, as well as a half octave below that for you infra-freaks.
With the Beta 50, as with all of the speakers, I applied an 80 Hz crossover
frequency in the bass management setup, as whatever the Beta 50 could do,
the CSW-10 subwoofer could do better, particularly if the R.A.B.O.S.
happened to be good for the room acoustics scenario, but we'll get to that.
The Beta 50 towers also offered binding posts that make bi-wiring and
passive bi-amping an option, though personally I wouldn't recommend
bothering with either. If you've got some otherwise good amps with limited
current delivery capacity that you prefer to keep for sentimental or
financial reasons, I'll sign on to passive bi-amping. As to the bi-wiring
thing, if anybody can track me down at CEDIA next to a white board, I can
show how bi-wiring might make a difference under certain unlikely
conditions, and why you wouldn't want that unless you like oscillations or
peaks at the crossover frequency. But hey, if you like it, you can do it!
Not only does the C360 have a handy adjustable leg on the back of the
enclosure to optimize the downward angle where the speaker is placed
substantially above the listening height, it is also a good example
of a center channel driver array done correctly.
The most typical MTM (Midrange Tweeter Midrange) type center channels,
though aesthetically pleasing in their slim profile and symmetrical layout,
more often than not suffer horizontal off-axis lobing in the midrange
spectrum, as the output of each spaced midrange driver is significantly
delayed relative to the other when listening to the side, and we get
selective cancellation at frequencies where the resulting phase shift is
close to some iteration of 1800 (5400, 9000, 12600, etc), and we thereby
find comb filtering that shifts in nature as you move, resulting in dialogue
difficult for those seated at the side of the couch to understand.
The C360 is instead a 3-way design, with a vertical, closely located
midrange and tweeter assembly (one 1” tweeter with one 4” midrange driver)
that will have just as even, if not more even dispersion than the Beta 50
towers. That arrangement is then augmented by two 6 ½” woofers to keep the
single mid from heaving large amounts of air with its wee cone. At lower
frequencies, even as high as 200 Hz, the wavelengths are long enough that
the degree of spacing between the woofers doesn't result in substantial
cancellation, even 450 off-axis.
For instance, if the drivers are spaced even two feet apart (in the C360,
they're only about 1 ½'), that results in a 1.4' distance difference when
listening 450 off axis, which is an extreme example. At 200 Hz, our
wavelength is about 5.5 feet, resulting in about a 900 phase shift,
not enough to cancel, but rather theoretically just a 3 dB dip due to the
lack of constructive summing. A 3 dB variation at 450 off-axis isn't
bad at all. Other examples are illustrated in the table shown below.
||Phase Shift (Deg)
|Big Dips (most cancellation)
Peaks (most not cancelled)
As the frequency increases, you can see that you'll get
really steep dips at 393 Hz, 1,179 Hz, 1,965Hz, and 2,750 Hz. You'd also, as
a result, have relative peaks (simply not cancelled output) at 786 Hz, 1,572
Hz, 2,358 Hz, and 3,143 Hz. Certainly not a smooth listening experience.
But, anyway . . . .
Going much higher in frequency with relatively wide spacing shows
the problems with a horizontal MTM array, where spaced midrange drivers
operate over a much wider range. Granted, 2 feet is relatively wide, even
for an MTM, and 450 off axis is on the edge of expected listening
areas, and 1100 ft/second is just an approximate speed of sound (which will
depend on atmospheric pressure and humidity), but it illustrates the point
of what could happen over the working range of a hypothetical midrange
driver in such a scenario.
As surround speakers, the ES250 speakers don't look unusual. There are two
sets of drivers oriented front/back, as many others, to potentially provide
a more diffuse surround field. Like the Beta 50 towers, the ES250 speakers
have dual binding posts, but not for the typical bi-wire/bi-amp options, but
rather to make use of the little switch on the other side. That switch
allows the speakers to operate in a bipolar mode (both sets of drivers
in-phase), dipolar mode (theoretically one set of drivers out of phase with
the other, though I suspect that they just switch the polarity of one
tweeter, as woofers out of phase would nullify almost all bass response), or
as a monopole (just one set of drivers working).
When using any of these
modes, you keep the shorting straps connected between the binding posts.
However, should you put the switch into bipolar mode and remove the shorting
straps, you can use the single speaker as two, to either use a single pair
as both surround and rear speakers, or to use a single speaker as the rear
pair in a THX EX or Dolby EX mode, or whatever other purpose we can find
useful. I settled on the simple bipolar radiation pattern for my needs,
directional enough for a specific pan, but spread enough to keep things from
clumping, though mileage will certainly vary with preference, placement, and
Getting to the Bottom - The CSW-10
(which is not formally part of the Beta series) is incredibly heavy for its size. The cone is pretty with its big fat light
gray rubber surround. The amplifier
is listed as capable of delivering 650 watts to the driver, though when
you're talking about a whole amplifier/speaker system, the rated amplifier
power doesn't really mean a whole lot without knowing the efficiency of the
rest of what it's driving.
The CSW-10 is a relatively small sealed system. Sealed systems are great in
many ways, but unlike reflex systems, the entire air displacement must be
fronted directly by the driver, and as such sealed systems generally have
less maximum output when compared to reflex systems at or slightly above the
tuned frequency of the particular reflex-based unit. In most cases, I've
preferred sealed systems for sound quality, in part because of the shallower
roll-off that tends to complement room gain to deliver good output below the
listed –3 dB cutoff spec, and that it's inherently easier to deliver tight,
controlled, smooth bass. However, there are always exceptions on both sides of
the fence, and I've certainly had the pleasure to witness some excellent
bass reflex subwoofers as well, so don't take my comments too seriously.
Where the CSW-10 actually starts to get more useful than your average bear,
in terms of features, is R.A.B.O.S. This nice collection of capital letters
stands for "Room Adaptive Bass Optimization System". When speaking to people
I'm not trying to impress, I would call this a notch filter and some dealie
whops, such as an SPL meter, a circular variation of a slide ruler to derive
settings from a plotted curve, a CD with test tones, and some paper to plot
your room response. Basically, it means that you place the subwoofer and plot
the response using the test tones on the included CD. If the
arrangement results in any substantial room response peaks that makes for
‘one note' booming bass that lacks definition and poise, either plug in your
numbers on the Infinity web site, or adjust the sliding dial so that the
curves fit the plot, and you get your settings for the notch filter. This is
a truly handy and useful feature.
This round, I didn't have any use for the offered room compensation system,
but I can attest to the value of well-calibrated notch filters with
subwoofers to address problematic acoustics. I currently control room
resonance and minimize cancellations with multiple subwoofers. In fact, with
my current arrangement, a single subwoofer just won't work at all with my
combination of available locations and listening position, the very reason I
insisted on two CSW-10s or none at all.
However, there was a time when I had a pretty hefty spike at about 44 Hz
with a different room orientation and a single subwoofer, which made the
bass unbearably overwhelming and distracting, regardless of the subwoofer
channel level. When I finally got the notch filter depth and width adjusted
on the Anthem AVM-20, it made a world of difference. Where before the bass
response was bloated, fat, subjectively slow, and lacking in control, the
result after applying the notch filter was exactly the opposite. Bass was
tight, lean, clean, but mean, subjectively ‘quick' in character, putting
forth well-defined attacks with little perceived overhang in sounds.
though I don't currently have use for notch filters, I advocate their use
handily when subwoofer placement options don't suffice in controlling ‘room
boom'. One thing about this variation that I thought quite neat was the fact
that when the R.A.B.O.S filter attenuates the peak, it also compensates the
broadband level so that the average amount of bass won't decrease. Of
course, you could always recalibrate the level after flattening the
response, but I thought it was nifty nonetheless.
Back to the Whole of It
While I've always been most critical about music listening, these days my
A/V gear does more children's movies than anything else. Many of these
soundtracks are entirely deserving of good equipment, and occasionally
Overall, I would say that the first thing I noticed about the sound was how
little I noticed. Any flaws inherent to these loudspeakers sit on the subtle
side. The sound overall is smooth, but not smeared, the tonal balance is
even across the entire range, as opposed to thick and chesty or bright and spitty,
and the transition between each speaker across the soundstage is gradual,
consistent, and seamless.
With the pair of CSW-10 subwoofers, I never found the amount of extension
lacking, or their dynamic capabilities limiting under normal use. The quality of the sound doesn't hit your face and
scream, “Hey listen to me, I'm a subwoofer”, but rather does what it should,
simply put the sound into the room such that one might just think that the
Beta 50 tower loudspeakers had ridiculously good bass extension, or better
yet let you forget about the speakers and listen to the performance. While
the CSW-10 isn't an Atlas compared to the bigger Velodyne, M&K, or SVS
units, it's no miser on performance, and when it belts it out, it's utterly
sweet, and even seismic in measured amounts. Whether during the more
infrasonic-heavy scenes of Finding Nemo, or in the beginning of Toy Story
2 when Buzz Lightyear breaks into Emperor Zurg's Fortress, the CSW-10
delivered the goods in the lowest registers.
The C360 and the Beta 50 towers formed an impressive front array. Even
though I'm generally an advocate for identical speakers for the left,
center, and right channels, as I commented before, the blending of the whole
system was just fine across the front, and around the rears the character
remained constant, with even, smooth pans from front to rear or left to
In terms of articulation, I never felt myself straining to understand
dialogue, especially in Chinese (Hero is a fantastic movie, and
fantastic-sounding, I must buy!) My neighbors commented more than a few
times how much they liked it as well. These Betas certainly
passed the pet test, perking the ears of my cutie pie Rottweiler whenever
sounds of dogs or wolves came up, for whatever indication that might make.
My dog is pretty old.
When it comes to dynamic limitations, assuming adequate amplifier power,
these things will play most anything loud enough to cause hearing damage
without serious subjective distress. I don't generally listen very loud, and
am of the ilk who thinks that with most material, if somebody thinks that
reference level is anything other than ‘show off your hardware for a few
minutes' volume, they're nuts, and probably on their more rapid way to at
least partial deafness. But, with loudspeakers, headroom is nice, as it
means less dynamic compression and distortion at any level, and when you get
near the upper end of the SPL range, it's always nice when things don't
sound loud, in that horrid shrieking way, regardless of the decibel level.
It's hard to say a whole lot about movies. I tend to get distracted
following the story. Not surprisingly, I didn't realize how truly good these
speakers were until I seriously took some time for myself to have at ‘em
with some good music.
Music Listening Notes
Roxy Music - Avalon, "Avalon". Rounded but
controlled bottom, good sense of space, not as precise in localization as my
S-150Ps, but altogether open without being whacked out all over the place.
Nice balance, able to hear the recording, but not assaulted by it.
John Fogerty - Déjà vu All Over Again, "Déjà vu All Over Again".
Nice plink in the strings of guitar, kick drum good and thumpy without
getting fat, but easy to hear the nature of decay. Vocals clear, not overly
spitty or laid back. Proximity of the microphone was easily apparent, but by
no means dominated the focus of attention. Overall, the panorama flowed
rich, with a vibrant presentation, but absolutely non-fatiguing. Even the
somewhat obnoxious and uber-compressed "She's Got Baggage" was enjoyable
enough to sit through its entirety, almost. I skipped to "I Will Walk With
You" with its occasionally complex harmonies of lilting guitars and bass
backup to lyrics, and "Rhubarb Pie", a banging folksy down home treat, during
which I thought to myself, “Man, I like this bass,” but was also happy to
just sit and enjoy the music between occasional notes.
Ben Harper - Burn to Shine, "Suzie Blue". The ‘Voice in an old box and noise'
recording, vs. the subsequent ‘outing' had a degree of contrast, though the
‘in a box' sound wasn't as contained as I like it, and as such not as
dramatic when it opens up. Still, the staging had a nice blend of instruments
without blurring. Horns and woodwinds maintained a natural character.
Banjo, suspiciously but positively ‘over there in the corner' behind and
beyond the physical loudspeaker. Vocals less well-placed, kind of floating
ambiguously, in part due to the more ‘open' and ‘tall' soundstage, but in
part due to the nature of the recording, with little reverberant context
given to the vocal track. Following, "Steal My Kisses", begins with a ‘spit
box' performance accompanied by an awesome bass assault. Clean attack lines,
clean delineated percussion, cymbals didn't have quite as much zing as I
sometimes like, though I prefer a little softness in the treble compared to
obviously too hot. Besides, it didn't sound rolled-off at all, just a wee
Diana Krall - Love Scenes, "All or Nothing At All". An audiophile favorite, was
rendered in full glory. Open, expansive, ‘you are there' kind of presence.
With a wonderful voice, great instruments, and a superb recording, it was an
absolute pleasure, even if not nearly my musical favorite.
Bjork-Selmasongs, Music from the Motion Picture Dancer in the Dark,
"Overture". Easily heard people breathing, speakers were able to convey depth
behind them simultaneously portraying the most immediate. In the following
track, "Cvalda", machinations of industrial sonics sewn and thrust together in
an audio paella with Bjork's incessant and exquisite vocals, pulled some
soundstage and bottom-end tricks that actually colored me startled. The mix,
though vivid and wild, is in many regards a complete mess of carefully
tossed chaos, but I suspect that much of it is the point. A lot of what's
happening is absolutely nuts, with very complex passages and orchestrations,
and the Beta 50s put that through without dumbing it down to a homogenous
Bjork- Gling Glo- "Kata Rokkar". I had not an iota of a hint of what
she's saying, but through this entire Icelandic Jazz album, some of her
recording of vocals and instrumentation is fabulous. Bass was naturally fat,
piano lively and open, percussion entirely natural and unrestrained.
During "Pabbi Minn", brushes on the drum skins were great. Heck, this whole
album is fantastic, and the Infinity Beta 50s and the CSW-10s didn't seem to
be holding anything back. When I first listened to the Debut album back in
school, I don't think I would have believed anyone who would have told me
that I was likely to enjoy Icelandic Jazz. I'd venture so far to say that if
you at all like anything Bjork has done, you MUST get the Gling Glo album!
As far as this relates to a product review, the Beta 50s and the CSW-10 subs
did it magnificent justice.
Before there were diapers filled up to little belly buttons with mess,
before I had to scramble to pay a mortgage and all of those annoying bills
that seem to come with it, before sharing feelings and thoughts with someone
you loved was a responsibility and compulsion, I used to just sit for hours
listening to music, a facet of my life I looked forward to daily, often at
the exclusion of almost anything else. That is why I got into Hi-Fi. The
Infinity Betas are
something I could easily live with on a long-term basis, and one of the
better offerings I've had the pleasure to get my hands on in some time.
Truly fine products, indeed. If you're in the market, don't mind looking in
the mainstream, and have a good dealer handy, I certainly do recommend a
test drive, preferably at home!
- Colin Miller -
Relevant Equipment used for this review and comparison.
Technics DVD-A10 DVD-V/DVD-A player
M&K S-150P Monitors
M&K S-250P Surround Monitors
SVS B-4 (parted into 4 individual sealed systems)
Crown K-1 power Amplifier (Subs)