The
challenge was to create a reasonably small but sccurate speaker system that
would not be so inefficient as to require an inordinately large amplifier to
drive it, and yet be capable of delivering clean, high output sound pressure
levels when used with powerful program equipment.
The BIC
Venturi Formula 2 more than fulfills that objective . It is the most sensitive,
highest power handling speaker system of its size ever offered.
It is result
of not one, but several technical inventions and innovations carefully
calculated to bring a new standard of performance to the home comparable to
theater and concert hall requirements. And this is achieved with an accuracy of
reproduction and economy of power that should satisfy the most critical musical
tastes and limited budgets.
The
enclosure is sturdily constructed to grade 1 furniture standards and finished
in scuff-resistant, walnut polymer-coated wood. It is free of resonances and
other spurious vibrations which add unnatural colaration (''tubbiness'',
''ringing'' or ''tunnel-like'' sounds), often mistaken as ''bas''.
A new type
sonicall transparent atractive foam grille is available in a choice of black,
brown, beige, burnt orange, blue and red. The grille can be resprayed to any
other desired color.
An optional
base, model VB-2, enhances the appearance of the Formula 2 when placed on the floor.
Musical
Dynamic Range
As music
increases in sound level, the loudspeaker should remain faithfully in step at
both the lowest and loudest passage, in many systems the speaker doen's
"take off" until it is driven fairly hard and then at same maximum
point is unable to produce more output sound to match the greater musical
modulations. Some systems at this point exhibit "cone beakup" and
other forms of distortion, or incur physical damage to voice coils,cones, etc.
System with these problems (usually greater as the efficiency decreases) are
not capable of wide 'dynamic range".
Since the
Formula 2 is extremely efficient and can also handle high electrical input
power with aplomb, its dynamic range will satisfy the critical listener, on all
kinds of music and program sources.
Super
tweeter
Although the
"midrange" Biconex™ horn reproduces frequencies to actually well
beyond 15,000 Hz, where most modest-sized speaker systems end, our
investigations into psychoacoustic phenomena reveal a need to extend aurally
perceptive response to at least 20,000 Hz or beyond, in order to preserve
original sonic balance and hence musical timbre of instruments originating in
the lower frequency ranges. This is particularly so in the Formula 2 because of
its extended low frequency response and high energy levels. Although covering
less than one musical octave (15,000 to beyond 23,000 Hz), a newly designed
high efficiency high power capability super dome tweeter completes the system,
and accurately handles the complex musical waveforms which contain harmonics
extending into this ultra sonic range.
Dynamic
Tonal Compensation™ (D.T.C.)
The ability
to hear different frequencies changes with sound level. At
"discotheque" levels, most frequencies are heard equally. As the
level decreases, less of the treble range and still less of the bass range is
discerned. At moderate home listening levels and especially at
"background" music levels, mostly the midrange is heard. Amplifier
"loudness" or "contour" switches employ a fixed rate of
compensation, but this is severely compromised by the efficiency of different
speakers and further upset by amplifier volume control settings.
The Dynamic
Tonal Compensation circuit (patents pending) automatically adjust the
relationship of the midrange to the bass and treble ranges, in conformity with
the Fletcher-Munson curves which have measured this human trait. Thus, as the
amplifier volume control is changed the speaker alters its response to provide
the ear with aurally flat response. All the music can now be heard all the
time, regardless of how soft or loud it is being played. A defeat switch and
continuously variable "Brightness" control on the speaker's front
panel, enables the conventional use of the speaker if desired. Amplifier tone
controls can still be used in the normal manner. The D.T.C. control board is
located behind the removeable grille, for easy accessibility.
Midrange
To provide a
proper match to the exceptional efficiency of the bass section, the Biconex™
Pyramidal horn/compression driver unit (patents pending) was developed. To
eliminate the need, as in other speakers, to interrupt the critical.
Ear-sensitive midrange spectrum with a distortion producing crossover network,
the operating range of this unit is 1500 to 15,000 Hz. The wide-angle
deispersion pattern is uniform in all directions, permiting the cabinet to be
used horizontally or vertically, as decor and physical needs dictate. A new
inert material used in the horn totally eliminates metallic coloration of
sound. The specially designed driver unit provides both an exceptionally smooth
response throughout its assigned frequency range and an unusually high power
handling capability to match the BIC Venturi bass section.
Bass
The
principle of the BIC Venturi systems (patents pending) is now applied for the
first time to speaker enclosure design. Briefly, it operates as an acoustic
transformer in the bass range, converting low magnitudes of energy to levels
many times greater and, additionaly, purer than would otherwise be possible
from a woofer used in enclosures of other types. Utilizing a specially designed
8" woofer, bass notes as low as 30 Hz are solidly reproduced with
thattight, clean sound which denotes excelent transient response and freedom
from audible harmonic distortion.
Power
The
sensitivity of the BIC Venturi Formula 2 is so high, that amplifiers or
receivers legitimately rated at as low as 15 watts RMS per channel will produce
more than adequate sound levels for normal home listening. The Formula 2 is
from 100 to 400% more efficient than "acoustic suspension" type
systems, therefore requiring much less amplifier power.
On the other
hand, the Formula 2 can handle amplifiers and receivers rated as high as 75
watts RMS per channel, with ease and reliability, providing sound pressure
levels rivaling the loudest concert hall passages and the noisiest
discotheques. Actually, the Formula 2 is capable of even greater electrical
input power, but its maximum rating is intentionally given as 75 watts since
such an amplifier is capable of producing 150 watts when driven to
"clipping" … a form of amplifier distortion. Even under such
conditionas, the Formula 2 can take it.
Specifications
Maximum
Power RMS Rated Amplifier: 75 watts per channel
Effective
Response: 30 - 23,000 Hz
Dispersion: 120° x 120°
Impedance: at no time under 4 Ω
Controls
Manual :
Continuously Variable "Brightness" Control
D.T.C. :
"Automatic" with defeat switch
Driver
Components:
Woofer
: 8" heavy Duty
Midrange
: Biconex™ Horn/Compression Driver
Super
Tweeter : Dome
Front
Grille: Removable reticulated foam
Dimensions
(H x W x D): 19 ¾" x 12" x 11 ½"
Weight: 30 lbs (shipping)
Optional
Base: Model VB-2