The JBL Metregon (1960) is the first speaker system to
offer full-field stereo reproduction in an enclosure of moderate size. Two
completely separate full-range speaker systems are housed in the Metregon.
Sound from these two sets of speakers is integrated by the curved refractor
panel, making use of the same acoustic principles as the JBL Ranger Paragon.
The result is a full-dimensional sound stage six feet wide. There is no
"hole in the middle", no "split soloist", to mar the
illusion of a real performance.
Like the Paragon,
the JBL Metregon projects perfectly balanced stereophonic sound to every
listener in the room, regardless of seating position. Like the Paragon, it also
performs superbly as a monaural reproducing system.
The JBL Metregon C45
is selected by the pasadena Art Museum
for showing in tri-annual industrial design exhibition.
The curved refractor
panel used exclusively in JBL integrated stereo systems integrates the two
separate stereo channels into a single three-dimensional sound source. It not
only produces a smooth transition from one source of sound to the other, but
disperses the sound pattern over a wide area.
The two separate
full-range speaker systems housed in the Metregon face into the edges of the
refractor panel. Sound generated by these speakers tends to flow along the
curved surface of the panel. It is projected outward from the refractor by a
complicated interplay of reflection and constructive interference. The listener
hears sound directly from the loudspeakers as it is projected across the full
width of the curved acoustic refractor. Individual instruments are pinpointed
at the position they were recorded. The effect is comparable to dimensions
achieved when a moving picture is projected on a wide curved screen.
Since the JBL
Metregon generates a stereophonic sound field within the loudspeaker system
itself, there is no need to sit in a particular location to hear
three-dimensional sound. Every listener in the room hears a single blended
performance, just as if the artist were actually in the room.
Additional
loudspeakers which can be accommodated in the C45 enclosure.
Since both the low
and high frequency drivers face into the curved refractor panel, other JBL
loudspeaker systems, in addition to the 205 system , can be installed in the
Metregon. Pairs of JBL Extended Range Speakers D123, D130 or D131 can be used
alone. These can be built up to two-way systems by addition of the JBL 075 High
Frequency Driver and the N2400 Dividing Network. In addition, the JBl Stereo
Systems 201 and 282 can be installed.
The list of the
components used in the eight basic JBL systems compatible with the C45 Metregon
enclosure.
Loudspeaker
Components used in the JBL Metregon
The Metregon
reproducer is designed especially to match the JBl 205 loudspeaker system. This
consist of two matched sets of components. Each set includes a JBL 130A low
frequency driver, model 275 high
frequency driver, H5040 cast exponential horn, and N600 crossover network. The
bass driver are loaded by individual matched-reflex chambers. A low crossover
frequency of 600 Hz enables the radiant dispersion principle to be utilized to
best possible advantage.
Components
Specifications
JBL 130A - Maximum
efficiency low frequency loudspeakers designed primarily for use with the 175
DLH high frequency assembly. The 130A have 4" edgewound copper ribbon
voice coil and long magnetic gaps for crisp reproduction of bass tones.
Normally,a single 130A is used together with the 175DLH and N1200 dividing
network, in larger enclosures where two bass drivers can be installed. For
reflex or horn-loaded enclosures.
Impedance: 16 ohms
Power Capacity: 25 watts
Free Air Cone
Resonance: 29 cps
Frame: Rigid cast
aluminum
Field: Permanent Alnico V Magnet
Magnetic
assembly: 11,5 lbs
Weight: 23 lbs (shipping)
JBL 275 - This new
driver is a more massive version of the well-known JBL 175. Newly designned
magnetic circuit with increased gap energy results in improved linearity at
highest audio frequencies. For 2-way systems crossing over at 600 Hz
Impedance: 16 ohms
Flux density: 18,500 gauss
Voice coil
diameter: 1-3/4"
Power Capacity: 25 watts above 500 Hz
Weight: 15 lbs (shipping)
JBL H5040 - Cast
aluminum exponential horn. Used with 175
and 275 drivers in JBL systems crossing over at 600 Hz and above. Designed
primarily for JBL-Ranger Mertregon
Weight: 5 lbs (shipping)
JBl N 600 - The
dividing networks on this page are constructed of highest quality precision
components, hand wired and individually checked to meet precision component
tolerances. A 3 position switch allows the intensity of the high frequency
trasducer to be adjusted for optimum results in any acoustic surroundings. Used
with JBL 130A or 130B bass drivers and 275 high frequency driver
Attenuation: 12 dB per octave on each side of crossover
frequency
Crossover
Frequency: 600 Hz
Impedance: 16 ohms
Dimensions: 4-3/4" x 6" x 6-1/4"
Weight: 10 lbs (shipping)
The JBL C45
enclosure is available in the following fine wods and finishes: light or dark
Walnut, light or dark Mahogany, light Oak, Salem Maple, Natural Birch, Korina
and Ebony.
Dimensions
Height: 30"
Width (top): 73-11/16"
Depth: 22-1/2"