Thiel Audio Products PX05, CS2.4, SS2, PowerPoint Review Manual

Product Review

Thiel A u d i o

CS 2.4 / MCS1 / PowerPoint / SS2 / PX05

Home-Theater Speaker System

December 2004

By: Anthony DiMarco

[e-mail]

Coherent construction

Tight tolerances, flawless finishes, and hand-matched Amberwood
veneers result in the elegant and sophisticated appearance of the
CS2.4, MCS1, and SS2. Hyper-accurate CNC machines cut the MDF
parts of each hand-assembled enclosure. The PowerPoint’s thick,
alabaster-like ABS plastic shell is thermoformed, while its trapezoidal
shape keeps the driver’s baffle as close to the wall as possible.

According to Thiel, their Coherent Source technology ensures perfect
time and phase alignment between a speaker’s drivers. The CS2.4
and MCS1 use a 1" aluminum tweeter coincidently mounted to a

3.5" aluminum midrange cone. Jim Thiel prefers the term c o i n c i d e n t
to coaxial because proper time alignment requires that a driver’s
acoustic center outputs from the same geometric plane. While coaxial
drivers share the same axis, coincident drivers share the same axis
a n d plane. Thiel designs coincident drivers to be perfectly coherent
across their frequency range. The drivers are coupled with a tuned
mechanical suspension instead of a traditional crossover, which,
Thiel maintains, avoids distortion.

What defines the perfect loudspeaker? Thiel Audio founder Jim T h i e l
would say that a loudspeaker must possess a c c u r a c y, in the
broadest sense of the term. In other words, a loudspeaker should
have linear frequency response, low distortion, and perfect time
and phase alignment, or c o h e r e n c e. Although many loudspeaker
designers will cite low distortion and linear response as goals, very
few consider time and phase alignment critical to the overall sound.
Some believe the cost of implementing such technology far exceeds
the payoff, while others think the human ear is insensitive to the
difference between coherent and noncoherent loudspeakers.

Thiel’s website offers scientific data to the contrary. Their Coherent
Source (CS) technology is one of the hallmarks of the Kentucky­based company’s design philosophy. Thiel Audio doesn’t appear to
rely on pseudoscience or unsupported claims. The company claims
to be driven by research and development steeped in physics and
the scientific method.

Six Thiel speakers costing a total of $14,700 arrived on my doorstep.
The MCS1 ($2300) and pairs of CS2.4s ($4400/pair) and PowerPoints
($1300 each) didn’t bear much of a family resemblance (until I
looked at their drivers). The SS2 subwoofer ($4900) handled the low
bass, and Thiel’s PX05 passive five-channel crossover ($500) tied
everything together.

The bass frequencies must also remain in time and in phase with
the midrange and tweeter outputs. Because different frequencies
travel through air at the same velocity, the arrival times of individual
drivers’ waveforms will be offset if their acoustic centers are not in
the same vertical plane; the result, according to Thiel, is a poorly
defined image. The CS2.4’s slanted baffle guarantees that the audio
waveforms from the 3.5" coincident driver and the robust 8" aluminum
woofer arrive at the listener’s ears at the same time. And the CS2.4’s
first-order, phase-corrected crossover ensures that the waveforms
arrive simultaneously at the listening position.

The MCS1 center speaker also uses a first-order, phase-correct
c r o s s o v e r. However, this speaker’s flat baffle relies on two shallow,

6.5", polystyrene-reinforced aluminum woofers to keep low-frequency
output in the same plane, and therefore time-aligned, with the
coincident driver. The shallow woofers also allow the coincident driver
to be flush-mounted to the baffle, thus reducing the effects of cabinet­edge diffraction on sound dispersion.

The PowerPoint surround speaker’s coincident driver is a 1" aluminum
tweeter coupled to a 6.5" woofer cone. The driver’s dispersion
emerges at 90 degrees to the center of the tweeter, which, together
with the 45-degree baffle, directs output away from the adjoining
wall. According to Thiel, this prevents signal cancellation in the critical
midrange frequencies.

Although the SS2 subwoofer’s two 10" aluminum cones and compact,
room-friendly enclosure look conventional for a subwoofer, the SS2 lacks
the standard phase, gain, and crossover controls. Jim Thiel’s extensive
research has convinced him that room boundaries and dynamic
compression due to voice-coil heating are the two main things that

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affect subwoofer performance; he claims that the crossover and
phase controls available on most subs harm the subs’ f r e q u e n c y
response and integration with a set of main speakers. T h i e l ’s
SmartSub technology purportedly addresses all of these issues. A
1000W class-D amplifier supplies the grunt expected from a high­quality sub. The SS2 is designed to work with T h i e l ’s two-channel PX02
and five-channel PX05 passive crossovers, or the SI 1 Integrator
electronic controller.

Coherent setup

The CS2.4’s four poorly glued floor-spike inserts and the PowerPoint’s
easy-to-strip Sheetrock mounting anchors were the only problems
I experienced during setup. Thiel’s Shari Graham had a bottle of
adhesive on my doorstep the next day, and assured me that she
would discuss my Sheetrock-anchor issue with their parts buyer.
Such prompt attention reinforces the benefit of purchasing from
a company of T h i e l ’ s dedication and experience: Unlike the
functionaries who work for many faceless conglomerates, Ms.
Graham is empowered to solve customer issues on the spot. I
experienced the same high level of customer service from Thiel with
a used pair of CS1.2s I bought years ago, before I began writing
r e v i e w s .

I hooked up my Analysis Plus T1 spade lugs to the CS2.4s’ g o r g e o u s ,
well-spaced binding posts. The deeply knurled nuts easily clamped
down on the meaty spades. I immediately noticed that the 3.5"
drivers performed equally well horizontally and vertically off - a x i s .
Many speakers with a separate tweeter and midrange lose high­frequency sparkle and clarity when listened to from an angle and
not at ear height. Thiel’s 3.5" coincident driver did not have this
problem. The CS2.4s were much easier to place than my CS1.2s
had been. I was able to listen to music without sonic degradation
while playing on the floor with my son.

The MCS1 center speaker produced the same sort of fantastic off­axis sound. I first mounted the 60-pound speaker to a T h i e l - s u p p l i e d
Sound Anchor stand, but my wife and I agreed that the heavy steel
stand took up too much floor space and clashed with the room’s
décor. So we set the MCS1 on a piece of plywood atop our TV. The
sound quality and tonal balance remained transparent—the MCS1
produced uniform frequency response no matter where I or it sat.

My living area has its share of sonic challenges. My couch sits up
against a wall, which makes placement of surround speakers tricky.
I sent digital photos of my room to Thiel, who recommended mounting
the PowerPoints on the sidewall within a foot of the rear wall, pointed
down toward my listening position. I placed the PowerPoints about
8" from the ceiling, which resulted in an open, nonlocalized surround
fill. The SS2 subwoofer took its place at the far end of my couch,
firing across the CS2.4s’ soundstage.

The SS2 has a single-ended RCA connection for LFE input and a
balanced XLR connection for interfacing with the PX05 passive

crossover. Both connections also have a pass-through so multiple
SS2s can be daisy-chained. The extremely well-built PX05 crossover
takes high-level signals from either the speakers’ terminals or an
a m p l i f i e r ’s output and modulates them into a single, balanced,
line-level signal that feeds the SS2. Although the PX05’s binding
posts are of very high quality, they’re too close together for spade
lugs; banana plugs worked much better. The LFE signal came
directly from my McCormack MAP-1 preamplifier’s subwoofer output.

The SS2 has a simple three-button LED interface. One button selects
each of the sub’s two settings, while the others adjust the settings
up or down. The first setting is for LFE level. The second goes to the
heart of T h i e l ’s SmartSub design philosophy: boundary compensation .
According to Thiel, the SS2’s microprocessor-controlled a n a l o g
signal processing programs the distance between the sub and two
surrounding walls, and cancels out the negative effects of a room’s
boundaries on the bass response. It took me two minutes to measure
and input the distances. What I heard after that was miraculous.

Coherent bliss

The Triplets of Belleville is a beautifully crafted animated film with
a bittersweet storyline. The film is almost devoid of dialogue, relying
instead on gestures and expression to define character and plot.
The sound design exhibits the same stellar craftsmanship — detail,
ambience, and unexpected dynamics abound. Chapters 6-8 drenched
me in the sounds of rain, subtle taps, whispers, and the bark of an
annoyed dog as a train rushes by. The Thiel system’s universally
brilliant high- and mid-frequency reproduction rendered with energy
and lush harmonic color this quirky world of a French cyclist and
his protective Grandma.

I have heard other systems demonstrate a seamlessly consistent
surround image, but I always get the sense that transducers are
reproducing the image. The Thiels took this behavior to the next
level by creating a 5.1 image that was so lucid, so composed, that I
forgot that there were loudspeakers in the room. The six T h i e l
speakers truly spoke with one voice.

I had no problem suspending my disbelief during the helicopter
crash and subsequent shoot-out in chapters 9 and 10 of Black Hawk
D o w n. The recently released Superbit version offers an excellent DTS
mix that wraps around the listener and drives home the concussive,
unpredictable experience of battle. Speakers that lack focus and
control can lose their way with such heavily layered soundtracks.
But the Thiels never sounded veiled, or lacked definition or impact.
Loud, soft, or tightly packed — all sounds remained absolutely clear
during even the most chaotic scenes.

The SACD of Peter Gabriel’s Up [Geffen 493388] is an excellent
test of bass-management transparency. The voice, instruments,
and bass are sent to discrete channels rather than being mixed to
all, making it easy to pick up on any crossover inconsistencies.
If the bass doesn’t seamlessly transition from a system’s main

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