Instruction Sheet
IS-MA60/125/250
Issued: 3-6-18
Lowell Manufacturing Company
100 Integram Drive
Pacific, Missouri 63069 U.S.A.
Call: 800-325-9660
Fax: 636-257-6606
Click: www.lowellmfg.com
3
Amplifier Block Diagram
Technical Specifications
Dimensions:
17" wide x 3.5" high x 13.5"deep,
431.8mm wide x 88.9mm high x 342.9mm deep,
Frequency Response: 50Hz-20KHz + 3dB (
Test signal inserted at aux input
)
AC Supply Voltage: 115VAC or 230VAC (Rear panel switchable) + 10%, 50/60Hz
Channel 7
Telephone
Page
Channel 6
Music
Channel 5
Mic/Music
Channel 4
Mic/Music
Channel 3
Mic/Music
Channel 2
Mic/Music
Switch Defeatable Circuit Mutes CH3-CH6
Channel 1
Mic/Music
Bass
and
Treble
Controls
Master
Volume
Control
Mixing
And
Control
Section
Power
Amplifier
Circuit Mutes All Channels
MA60 60W RMS
MA125 125W RMS
MA250 250W RMS
8
W
70V
25V
COM
4
W
CH3
VC
CH4
VC
CH5
VC
CH6
VC
CH7
VC
CH2
VC
CH1
VC
Tape O ut
Preamp Out
Power Amp In
Fact ory Installed
Jumper
DC Supply Voltage: 24VDC (Max 10% deviation)
Power Consumption:
MA60
150W (if supply is AC)
5A (if supply is DC)
MA125
300W (if supply is AC)
8A (if supply is DC)
MA250
600W (if supply is AC)
16A (if supply is DC)
Shipping Weight: MA60: 22LBS.
MA125: 24LBS.
MA250: 29LBS.
Color:
Black Note: Black rack mounting brackets are included.
Speaker Level Outputs: Screw terminal strip, 4
W
, 8
W
, 25V, 70V,
MA60: 60W RMS, MA125: 125W RMS, MA250: 250W RMS
Tape Outputs: Dual parallel RCA-phono jacks, 1V @ 4.7k
W
output
Preamp (
“Pre”) Outputs: Dual parallel RCA-phono jacks, 1V @ 600
W
output
Convenience AC Outlet: 500W maximum unswitched outlet
Mic Inputs 1-5: XLR receptacle or screw terminals, 1mV @ 600
W
balanced,
Note: With channel aux switch depressed, XLR and screw terminal inputs still operate but are padded as line input
150mV @ 600
W
balanced.
Aux Inputs 1-6: Dual parallel RCA-phono jacks, Stereo converted to mono, 150mV @ 22k
W
Telephone Input 7: Screw terminal strip, 150mV @ 600
W
balanced
Power Amp In: RCA-phono jack, 1V @ 8k
W
Total Harmonic Distortion: Less than 1% at 1kHz at rated power.
Signal to Noise Ratio: 80dB (
Test signal inserted at Aux 6 input),
60dB (
Test signal inserted at Mic 1 input),
Tone Controls: Bass + 10dB @ 100Hz, 10dB @ 10kHz,
Phantom Power: 16VDC,
Shipped from factory with internal phantom power jumpers set “ON” for Channels 1-5.
To defeat phantom power,
remove cover and set jumper to “OFF”. Channel-1: see jumper JP1,
Channel-2: see jumper JP2, Channel-3: see jumper JP3, Channel-4: see jumper JP4, Channel-5: see jumper JP5.
Priority Muting: 3 levels of priority.
See section “AMPLIFIER MUTING-PRIORITY SCHEME” on page 7.
Weight:
MA60: 17LBS.
MA125: 19LBS.
MA250: 24LBS.