Acoustical – USM-1/S-1 System
Frequency Response
1
40-18k Hz +4 dB
Maximum SPL
2
Continuous 130 dB
Peak 139 dB
Maximum Peak (Music Signal) 144 dB
HF Coverage, -6dB points 70° horizontal x 60° vertical
Acoustical Crossover Frequency 900 Hz
USM-1 Loudspeaker
Transducers
Low Frequency MS-15 15-inch cone driver, 12 ohms
High Frequency MS-2001A 2-inch throat compression driver, 8 ohms
High Frequency Horn 70 degree modified radial
HF Network DC blocking capacitor
Enclosure 2.3 cu. ft. vented, multi-ply Finnish birch
Finish Black textured
Protective Grill Hex perforated metal, powder coated, charcoal-
grey foam covering
Connector EP-4 male, EP-5 male (Europe only)
Rigging (optional) Aircraft pan fittings or
3
⁄8"-16 or M10 x 1.5 nut plates
Physical Dimensions 21" W x 24
1
⁄4" H x 18
1
⁄4" D
Weight 82 lbs. (37.3 kg)
S-1 Control Electronics Unit
Input Type
3
Active balanced ISO™ input, 10k ohms, 5k ohms per leg
Output Type Active push-pull, will drive 600 ohms
Maximum Input/Output Level
Balanced +26 dBu
Unbalanced +20 dBu
Hum and Noise
4
-90 dBV
Dynamic Range >110 dB
Sense Inputs 100k ohms true differential
Low-Frequency Delay Type Active all-pass
Driver Protection Circuitry
Low Frequency RMS limiter and excursion limiter
High Frequency RMS limiter and excursion limiter
VHF Peak limiter
Indicators
Sense/Gain Detect, Hi and Lo Green/Red LEDs
Limit, Hi, Lo, and VHF Red LEDs
Safe Green LED
Power Supply Green/Red LED
Controls
Front Panel Input attenuator, AC power switch
Preset Panel Lo Cut switch, Safe switch, VHF switch, VHF control
Connectors
Balanced Inputs/Outputs 3-pin XLR (A-3)
Sense Inputs Banana jacks
Power 90-105/180-250 VAC, 50/60 Hz (rear-panel switchable)
Physical Dimensions 19" W x 1
3
⁄4" H x 7
3
⁄4" D standard rack mount
Weight 8 lbs. (3.6 kg)
USM-1 Specifications
Note 1:
Measured 1 meter on-axis to
high horn, half-space con–
ditions, pink noise input, in
third-octave bands.
Note 2:
Loudspeaker driven with “A”
weighted noise (peak-to-RMS
ratio
≈
12 dB), with amplifier
rated at 600 W/channel at
8␣ohms. The USM-1 will accom-
modate amplifiers capable of
output levels up to
±
140 vpk.
Note 3:
ISO™ input: Pins 1, 2 and 3 are
transformer isolated, shell is
connected to chassis/AC
mains ground.
Note 4:
“A”- weighted, unbalanced.
