Overview: The THIEL CS3.7 floor-standing loudspeaker incorporates
several new innovative design techniques that greatly improve performance in a
three-way, floor-standing loudspeaker. The CS3.7 delivers a
much purer and more open midrange and lower bass response coupled with a sweeter and
smoother high frequency performance than conventional three-way loudspeakers.
The CS3.7 incorporates THIEL's latest innovative driver technology, rugged
cabinet construction, and phase/time correct Coherent Source design. All-metal
diaphragm, low-distortion drivers are used for outstanding tonal response and
the advanced phase correct crossover design greatly improves spatial fidelity
and clarity. The CS3.7 achieves the following major performance attributes:
- Extremely accurate tonal response
- Very high resolution of detail
- Truly realistic and natural imaging
- Preservation of dynamic contrasts
Driver Technology
Enclosure Design
Connections
Mounting Options
Warranty Information &
Break-In Period
Driver Technology
Driver Design: The CS3.7's drivers represent state-of-the
art technology and engineering. Unique short coil/long gap motor systems
dramatically reduce distortion; very rigid aluminum diaphragms eliminate
resonance coloration for exceptionally uniform frequency response; long
excursion motor structures provide greater output capability for realistically
high volume levels; and copper rings are used for magnetic field stability to
greatly reduce distortion from secondary effects.
- High Output, Low Distortion Tweeter: The CS3.7 features a 1"
aluminum dome tweeter with 64 g (2.3 oz) neodymium magnets, a copper pole
sleeve, a short coil/ log gap design with 3 mm Xmax, and is coincidently
mounted with midrange. The CS3.7 tweeter provides much lower distortion and
higher output. This is accomplished in spite of a size small enough to mount
coincidently with the midrange driver by a unique long gap motor system that
uses a set of four radial and one axial neodymium magnets with a total
weight six times that of a typical neodymium powered tweeter. In addition,
the tweeter provides the complete absence of any coloration-producing
diaphragm resonances in the audible range, a very wide operating bandwidth
and very low power compression. The result is high frequencies of utter
neutrality and effortless dynamics.
- Midrange Driver: The CS3.7 features a 4.5" midrange with a
wave-shaped aluminum diaphragm, 3" diameter voice coil, 115 g (4 oz)
neodymium magnet, copper pole sleeve, short coil/ long gap design with 6 mm
Xmax, and die-cast chassis. The
midrange driver should precisely reproduce every musical nuance while
introducing not even a trace of its own colorations or distortions caused by
diaphragm resonances or electromagnetic nonlinearity. The CS3.7 features a
new midrange diaphragm that advances midrange performance much closer to
this ideal. The midrange driver's diaphragm is constructed with an entirely
new shape that provides far greater stiffness than typical diaphragms, even
those made from exotic materials. The diaphragm is shaped with corrugations
that are oriented from the center outward (like spokes) and act a little
like small I-beams to provide enormous strength in that direction. The large
diameter voice coil attached to the diaphragm gives it strength in the other
direction--around the circle. This design achieves such great stiffness that
the diaphragm continues to vibrate perfectly, as one unit, all the way up to
20 kHz, usually considered the upper limit of human hearing.
This new diaphragm geometry also
has a second important benefit that derives from its shape. The diaphragm is
basically flat and therefore has virtually no detrimental effect on the
tweeter's output, unlike a normal cone shaped diaphragm that alters the
sound of a tweeter mounted in its center.
- Woofer: The CS3.7 features a 10" woofer with a wave-shaped
aluminum diaphragm, 3" diameter voice coil, 5 lb magnet in a 13 lb
structure, copper pole ring, copper pole sleeve, short coil/ long gap design
with 14 mm Xmax, and die-cast chassis.
The woofer also utilizes an innovative diaphragm that is basically
flat and therefore reduces the diffraction of the midrange energy usually
caused by the woofer's conical cavity. The massive magnet powers a very high
output and low distortion long magnetic gap and distortion is further
reduced by the use of a heavy copper pole ring and a copper pole sleeve that
reduces inductance nonlinearity. The large 3" diameter voice coil allows
high power handling. The very low frequencies are augmented by a 10" passive
bass radiator with a wave-shaped diaphragm which avoids the resonance and
noise problems of a ported enclosure.
Crossover Network: The CS3.7 crossover is a true first order acoustic
type that provides the utmost in spatial and depth imaging performance as well
as overall realism. This is the only type of crossover that provides complete
accuracy of amplitude, phase, time, and energy, and therefore the only type that
does not distort the musical waveform. Proper application of this
gradual-transition type of crossover requires the use of more expensive drivers
with wider frequency ranges than are required for use with common
quick-transition crossovers but the benefits also include improved uniformity of
the speaker's output in all directions.
The CS3.7 crossover is meticulously engineered to achieve extreme tonal
neutrality and is constructed with extensive use of polypropylene and custom
polystyrene capacitors.
Time and Phase Coherent: As with all THIEL loudspeakers, the CS3.7 is
completely time and phase coherent for much greater sonic realism. THIEL's
Coherent Source technology achieves the elimination of both time and phase
distortions that cause alterations in the reproduced musical waveforms of most
loudspeakers. Eliminating these distortions results in enhanced realism,
clarity, transparency and immediacy as well as improved imaging and soundstaging
in both the lateral and depth perspectives. Phase coherence in the CS3.7 is
achieved by utilizing a sophisticated first-order electrical crossover system in
conjunction with unusually wide bandwidth drivers. Time coherence is achieved by
placement of the drivers on a baffle that is sloped at the correct angle to
cause the sound energy from each to reach the listener at the same time.
Power Requirements: It is important to have enough power to play at
the level you desire without distortion. If high sound levels are desired, the
CS3.7's are designed to be used with amplifiers rated up to 600 watts per
channel (into 4 ohms). The CS3.7 is of high efficiency (90dB) and therefore can
work well with smaller amounts of power from a quality amplifier.
Enclosure Design
Cabinet Construction:
The cabinet plays an enormously
important role in the quality of music reproduction and so the engineering of
the CS3.7's cabinet incorporates several innovations that contribute to the
speaker's stunning clarity, its utter tonal neutrality and its exceptionally
realistic imaging. The CS3.7 utilizes an aluminum cap,
machined aluminum front baffle, and 15-layer ply cabinet walls to practically
eliminate unwanted vibration for utter tonal neutrality and exceptionally
realistic imaging.
- Aluminum Cap: The CS3.7 cabinet top is made of formed aluminum
whose shape provides several important advantages. First, it provides
enormous strength, virtually eliminating unwanted vibration. Also, its
rounded shape around the midrange eliminates diffraction of energy from the
mid and tweeter. In addition, the rounded shape helps minimize resonances
within the cabinet.
- Cast Aluminum Baffle: The speaker's front baffle is machined from
aluminum, a material more than 30 times as strong as the usual MDF. In
addition to reducing unwanted vibrations, aluminum also provides a rigid
mounting of the drivers so they cannot move, even a miniscule amount, in
recoil from the forces they generate to accelerate the diaphragm. Also, the
baffle's sloping angle positions the drivers for proper time coherence.
- Cabinet Walls: The speaker cabinet's most important function is
to completely contain the energy generated by the drivers to the inside of
the cabinet. If even a miniscule amount of this internal energy escapes
through vibration of the cabinet walls, distorted sound will be generated
that will obscure the music's delicate details. Cabinet wall motions of even
one ten-thousandths of an inch or less will produce audible distortion, and
so it is very important that all cabinet walls are as strong and rigid as
possible. In this regard the CS3.7 performs extraordinarily well, with all
the cabinet elements innovatively engineered to provide exceptional
rigidity. The construction of the
cabinet sides also plays its part in the CS3.7's rigid, low vibration
cabinet. The sides are made of 15 layers of hardwood laminated together into
a curved shape under high pressure. This results in a much stronger panel
than usual, with the curves adding greatly to its rigidity. The rounding at
the front of the speaker also reduces unwanted diffraction and the gentle
rounding along the cabinet sides also creates non-parallel walls to minimize
internal resonances.
- Sloping Front, Rounded Edges: Another cabinet function is to
position all the drivers properly so that the listener hears the sound of
each driver at the same time, preserving the sound's timing information.
Because all of the sound's harmonics are heard in perfect synchrony, all the
music's spatial cues are reproduced naturally. The CS3.7's sloping front is
designed to achieve time coherence between the sonic output of the woofer
and the midrange/ tweeter array. Another task the cabinet must perform is to
allow the sound from the drivers to radiate freely without encountering
cabinet edges or cavities that will diffract some of the energy, causing
interference and delayed sounds that produce tonal colorations and obscure
spatial information. In this regard also the 3.7 provides exceptional
results with its gently rounded cabinet top and sides.
Note: The CS3.7 is
available in a wide variety of exquisite, real-wood, laminate, and painted
cabinet finishes, finely crafted to enhance any home environment including Amberwood, Black Ash and Natural Cherry. THIEL CS3.7 cabinets possess a high quality lacquer finish
that is both beautiful and very durable. Any furniture care product such as
Pledge, Johnson's, or Endust can be used to keep the cabinets clean.
Magnetic Grille: The CS3.7 grille is attached magnetically to the
front of the speaker. The grille is designed to not produce diffraction so there
is no sonic reason to remove it. If you do need to remove the grille, carefully
pull the grille frame away from the front of the speaker. When replacing the
grille, line up the grille with the baffle's inlay edges.
Note: The grilles can be cleaned of dust by using an upholstery
attachment of a vacuum cleaner. To prevent damage to the tweeter, take care
not to push the cloth in toward the top of the grille
Connections
Binding Posts: The CS3.7's input terminals are located on the lower rear
of the speaker cabinet. The CS3.7 uses binding posts that accept several
types of wire connections (will not accept dual banana plug connectors but
single banana plugs can be used). The input terminals are designed to be easily
tightened by hand or a 1⁄2 inch nut driver can be used. The speaker's input
terminals are color coded to facilitate that both speakers in a stereo system
are wired in the same polarity for maximum speaker performance. The speakers
should be connected to the amplifier with high quality cable to ensure minimal
loss of power and proper control by the amplifier.
Note: The CS3.7 is a very high quality sound reproducer and will
benefit from use with the best associated equipment. Since it is extremely
accurate, it will reveal sources of distortion generated elsewhere in the
system. For example, distortion resulting from poor recordings or inferior
electronics will be reproduced accurately. Also, the quality of the
interconnect cables and speaker cables will significantly effect the
performance of the system
Mounting Options
Placement: The CS3.7s are relatively non-critical to room placement
and will provide good results from almost anywhere. However, here are some
guidelines to help you achieve the best sound from your speakers. Speaker
placement will affect the accuracy of timbre, spatial performance, and bass
performance.
- Distance From Walls: THIEL speakers, and most others, sound best
if they are placed well away from all walls. Such placement optimizes
imaging and depth, and musical timbres are reproduced with the least
coloration because it allows the initial sound coming from the speaker to be
distinctly separated in time from the secondary sound of wall reflections.
If reflections are heard too quickly after the primary sound, your brain
tends to interpret them as part of the initial sound, causing the perceived
timbre to be altered and the spatial characteristics to be confused. If you
experiment, you will notice a major improvement in openness when the
speakers are even two feet from the rear wall instead of one. Ideally, the
speakers should be three feet from the rear wall and five feet from the side
wall. Also, it is not desirable for large objects to be placed near the
speakers since these will also be a source of unwanted early reflections
that reduce imaging accuracy.
- Spacing: Because of their very wide, even dispersion of energy,
THIEL speakers should usually be placed farther apart than most. Optimum
imaging is usually achieved when the speakers and the listener form an
equilateral triangle, although this will depend on the width of the room (a
narrow room will require closer placement). If the speakers are too far
apart for a given environment, there will tend to be a "hole" in the middle
of the sound stage; if they are too close together, the image will be
compressed and will not achieve optimum width.
- Aiming: Preferred the imaging is obtained when the speakers are
pointed straight ahead rather than pointing toward the listener. This
placement produces the largest, most natural soundstage. However, toeing the
speakers in somewhat may produce more specific placements of instruments.
Also, if it is not possible to get the speakers far enough away from the
side walls, a toed-in position can be helpful to reduce the strength of wall
reflections.
- Bass: Bass response is also affected by speaker placement. In
general, when a speaker is close to a wall the bass response is stronger and
placing a speaker in a corner will make it even more so. In order to achieve
properly balanced bass, it is necessary for the speaker to be used in the
environment for which it was designed. THIEL speakers are designed to
provide accurate bass when positioned away from all walls-the same position
that provides the best imaging.
- Listener Position: The CS3.7s provide broad dispersion of energy
at all frequencies and therefore provide good results throughout a large
listening area. Best imaging is provided for a listener centered in front of
the speakers. Optimum phase and time alignment is provided only for a seated
listener who is eight or more feet away from the speaker.
Stabilizer Feet: Speakers positioned on a soft or uneven surface are
able to rock slightly and will vibrate in reaction to forces the speaker
generates to move the driver diaphragms. This motion slightly reduces the
music's clarity. To eliminate this effect, the CS3.7s can be used with the
supplied four gold stabilizer feet on uneven surfaces or on carpeted floors to
provide a more solid footing and allow the speaker to couple more firmly to the
floor. The speakers should be positioned before the stabilizer feet are
installed.
Note: Please be cautioned that the stabilizer feet can dent
hardwood floors and it is possible to mar the floor's surface if the
speakers are moved with the feet in place.
Warranty
Information & Break-In Period
Break-In Period: The CS3.7's, like most speakers, require a period of
playing before they perform optimally. The amount of time depends on how loudly
the speakers are played; more time is required if played
softly, less if played loudly. At least 50 hours at moderately loud levels are
required before the
speaker is performing near optimum. You should notice even more improvement
after 100 hours
of playing.
10 Year Warranty: THIEL warrants every THIEL model CS3.7 loudspeaker
against defects in materials and workmanship to the original owner for a period
of ten years from the date of purchase. THIEL will, at no charge, replace any
defective part and make any repairs necessary to ensure its proper performance
when the defective unit is returned to us postpaid. This warranty does not cover
damage due to accident or abuse and is void if the unit has been tampered with.
This warranty is automatic and no registration is required.
