Note 1:

Measured 1 meter on-axis,

half-space conditions,

pink noise input, in third-

octave bands.

Note 2:

Loudspeaker driven with

weighted noise.

Note 3:

“A”- weighted, unbalanced.

UM-1C Specifications
Acoustical – UM-1C/M-1A System
Frequency Response
1
70-18,000 Hz +4 dB
Maximum SPL
2
with amplifier rated at: 250 W/8 ohms/ch. 60 W/8 ohms/ch.
Continuous 125 dB 120 dB
Peak 135 dB 126 dB
HF Coverage, -6dB points 45 degrees symmetrical
UM-1C Loudspeaker
Transducers
Low Frequency MS-12 12-inch cone driver, 8 ohms
High Frequency MS-1401B 1.4-inch throat driver, 16 ohms
High-Frequency Horn 45 degree constant-directivity
HF Network Y-1PD
Function DC blocking and passive filters with alternate connection
terminal to adjust VHF response (16k peak or flat)
Enclosure 0.8 cu. ft. vented, multi-ply Finnish birch
Finish Black textured
Protective Grill Perforated steel screen, charcoal-grey foam covering
Connector Cannon EP-4 male, EP-5 male (Europe only)
Rigging (optional) Aircraft pan fittings or
3
⁄8"-16 nut plates
Physical Dimensions 14" W x 14" H x 22
1
⁄2" D
Weight 67 lbs. (30.4 kg)
M-1A 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 120 dB
Sense Inputs 10k ohms true differential, opto-isolated
Electronic Crossover Frequency 1600 Hz
Low-Frequency Delay Type Active all-pass
Driver Protection Circuitry
Low Frequency RMS limiter
High Frequency RMS limiter
VHF Peak limiter
Indicators
Sense, Hi and Lo Green LEDs
Limit, Hi, Lo, and VHF Red LEDs
Safe Green LEDs
Power Supply, Positive and Negative Green LEDs
Controls
Front Panel Input level control, AC on/off switch
Preset Panel VHF control, Lo Cut switch, Safe switch, VHF switch
Connectors
Balanced Inputs/Outputs 3-pin XLR (A-3), RTS
1
⁄4" phone jacks
Subwoofer Circuit Input Unbalanced,
1
⁄4" phone jack
(inserts Lo Cut, disables Level control)
Sense Inputs Banana jacks
Power 120/240V AC, 50/60 Hz (internally switchable)
Physical Dimensions 19" W x 1
3
⁄4" H x 7
3
⁄4" D Standard rack mount
Weight 8 lbs. (3.6 kg)