Meyer Sound Reinforcement Subwoofer 650-R2 User manual

Features
High power
Extremely low distortion
Long-term reliability
Rugged
Applications
Road use or installations
Sound reinforcement
Concert, film, and theater
Live music clubs and discos
Bass instrument amplification
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Inches
650-R2
Concert Series
Subwoofer
Meyer Sound Laboratories, Inc.
2832 San Pablo Avenue
Berkeley, CA 94702
( 510 ) 486-1166
FAX ( 510 ) 486-8356
The 650-R2 requires a professional qual-
ity two-channel power amplifier capable
of delivering 200 to 300 watts continuously
into 8 ohms or 400 to 600 watts into a
4 ohm load (drivers connected in parallel),
with a signal voltage gain of 20 dB (mini-
mum) to 30 dB (maximum).
The 650-R2 Subwoofer extends the
power bandwidth of Meyer Sound rein-
forcement systems to 30 Hz. Accurate and
rugged, this powerful subwoofer consists
of two 18-inch cone drivers capable of long
excursion with extremely low distortion,
set in a heavily braced 14 cubic foot vented
enclosure of multiple-ply hardwood.
Fitted with handles and a pair of high-
density rubber casters, the roadworthy
cabinet is dimensioned in submultiples of
90", the U.S. internal truck width standard.

650-R2 Specifications
Acoustical – 650-R2/B-2EX System
Frequency Response
1
30-100 Hz +4 dB
Maximum SPL
2
Continuous 130 dB
Peak 135 dB
Acoustical Crossover Frequency 100 Hz
650-R2 Loudspeaker
Transducers (2) MS-18 18-inch cone drivers, 8 ohms per driver
Enclosure 14 cu. ft. vented, multi-ply Finnish birch
Finish Black textured, carpet or weather protected (optional)
Protective Grill Perforated steel screen, charcoal-grey foam covering
Connector EP-4 male, EP-5 male (Europe only)
Wheels Two 3" diameter rubber tread rigid self-lube casters
Physical Dimensions 30" W x 45" H x 22
1
⁄2" D
Weight 176 lbs. (79.8 kg)
B-2EX Control Electronics Unit
Input Type Balanced (active), 47k ohms
Output Type Active push-pull, will drive 600 ohms
Maximum Input/Output Level
Balanced +26 dBu
Unbalanced +20 dBu
Hum and Noise
3
-90 dBV
Dynamic Range >110 dB
Sense Inputs 10K ohm true differential, opto-isolated
Driver Protection Circuitry RMS limiter, switchable excursion limiter
Indicators
Limit Red LED
Excursion Red LED
Sense Green LED
Power Green LED
Controls
Front Panel Input level control, AC on/off switch
Preset Panel Safe switch, Crossover Bypass switch
Connectors
Balanced Inputs/Output 3-pin XLR (A-3)
Sense Inputs Banana jacks
Power 120/240V AC, 50/60 Hz (rear-panel switchable)
Physical Dimensions 19" W x 1
3
⁄4" H x 7
3
⁄4" D
Weight 8 lbs. (3.25 kg)
Note 1:
Measured 1 meter on-axis,
half-space conditions,
pink noise input, in third-
octave bands.
Note 2:
Loudspeaker driven by power
amplifier rated at 400W into
4 ohms, weighted noise
signal source.
Note 3:
“A”- weighted, unbalanced.

The B-2EX Control
Electronics Unit
The 650-R2 operates as a system with
the B-2EX Control Electronics Unit (one
per channel). Optimized for use with Meyer
Sound subwoofers, and pre-aligned at the
factory, the B-2EX contains frequency
response and phase response alignment
circuitry, and Meyer Sound’s exclusive
SpeakerSense ™ driver protection circuitry,
incorporating RMS signal limiting and
switchable excursion limiting.
A single-channel device operating at
line level, the B-2EX is intended to be the
final component in the signal chain before
the power amplifier. It is connected in
parallel with the input to the system being
supplemented by the 650-R2, and incorpo-
rates a summing input for deriving a mono
subwoofer signal from a stereo program.
The factory-calibrated SpeakerSense
circuitry protects the 650-R2 loudspeaker
components from damage due to over-
heating under high power conditions. This
unique circuit continuously monitors the
power applied to the 650-R2 drivers, and
limits the B-2EX output when the safe
operating limits of the drivers are exceeded.
Until the onset of overload, the
SpeakerSense circuitry has no effect on the
signal.
Included in the SpeakerSense circuit
is a Safe switch, which moves the limit
point down by 6 dB and engages the
excursion limiter. This has the effect of
increasing the safety margin of the system,
and is intended to be used when extended
periods of overload are anticipated. In
addition to these features, the B-2EX
incorporates a Crossover switch which
engages/disengages the lowpass rolloff of
the subwoofer output. This feature may be
used whenever it is desireable to operate
the 650-R2 full-range as, for example, in
instrument amplification
The setup controls are located behind
a cover plate on the B-2EX front panel,
providing a means for securing the system
installer’s presets.
UltraSeries™ B-2EX Power
Sense Limit
∞
20
10 843
2
1
0
Attn dB
5
6
Excursion
Safe
Out
Crossover Safe

Architectural and
Engineering Specifications 650-R2/B-2EX
Meyer Sound Laboratories has
devoted itself to designing,
manufacturing, and refining com-
ponents that deliver superb sonic
reproduction. Every part of every
component is designed and built to
exacting specifications and
undergoes rigorous, comprehensive
testing in the laboratories.
Research remains an integral,
driving force behind all production.
Meyer strives for sound quality that
is predictable and neutral over an
extended lifetime and across an
extended range.
© 1994 Meyer Sound 04057034. 01C2
sensitivity, 101 dB SPL measured with
1 watt of pink noise, one meter on axis;
frequency response, 30 Hz to 100 Hz plus
or minus 4 dB measured with
1
⁄ 3 octave
pink noise, one meter on axis; output of
130 dB SPL one meter on axis with peaks
of 135 dB SPL when driven with weighted
noise. Total harmonic distortion shall
be less than 3% at 130 dB SPL one meter
on axis at 60 Hz.
Speaker enclosure dimensions are
45" H x 30" W x 22
1
⁄2 " D, weight 176 lbs
(79.8 kg).
Control Electronics Unit dimensions
are 19" W x 1
3
⁄ 4 " H x & 7
3
⁄ 4 " D, weight 8 lbs
(3.6 kg).
The speaker system shall be the Meyer
Sound 650-R2.
The Control Electronics Unit shall be
the Meyer Sound B-2EX.
The low frequency speaker system shall
consist of two 18" low frequency cone
loudspeakers front-mounted in a heavily
braced hardwood-plywood bass-reflex
direct-radiating enclosure, and a separate
Control Electronics Unit.
The Control Electronics Unit shall
contain a power supply capable of operat-
ing from a 120/240V AC, 50/60 Hz line,
a master level control, an active crossover
at 95 Hz, a switchable excursion limiter,
an RMS limiter for speaker protection, and
two active balanced summing inputs. The
Control Electronics Unit shall meet the
following criteria: total harmonic distor-
tion less than 0.1%; “A” weighted noise
level 110 dB below rated output of
+26␣dBu.
The speaker system, its companion
Control Electronics Unit, and a power
amplifier rated at 400 watts into 4 ohms
shall meet the following criteria: pressure
Meyer Sound Laboratories, Inc.
2832 San Pablo Avenue
Berkeley, CA 94702
( 510 ) 486-1166
FAX ( 510 ) 486-8356
Sound
engineering
for the art
and science
of sound.