Meyer Sound UPA-2C M-1A Control Electronics Unit

Power 120/240V AC, 50/60 Hz (internally switchable)

Physical Dimensions 19" W x 1

⁄4" H x 7

⁄4" D Standard rack mount

Weight 8 lbs. (3.6 kg)

The UPA-2C loudspeaker operates as a system with

the M-1A Control Electronics Unit (one per channel).

Optimized for the UPA series and pre-aligned at the

factory, the M-1A contains frequency response and

phase response alignment circuitry, and Meyer Sound's

exclusive SpeakerSense

™

driver protection circuitry,

incorporating both peak and RMS signal limiting.

A single-channel device operating at line level, the

M-1A is intended to be the final component in the signal

chain before the power amplifier. Its factory-calibrated

SpeakerSense circuitry protects the UPA-2C loudspeaker

components from damage due to overheating under

high power conditions. This unique circuit continuously

monitors the power applied to the UPA-2C drivers, and

individually limits the high-frequency and low-fre-

quency outputs when the safe operating limits of the

drivers are exceeded. Until the onset of overload, the

SpeakerSense circuitry has no effect on the signal.

Also provided is a switch-selectable Safe function,

which widens the safety margin of the system and is

intended to be used when extended periods of overload

are anticipated. The Safe switch and other setup controls

are located behind a cover plate on the M-1A front panel,

providing a means of securing the system installer's

presets.

To enhance the effectiveness of the UPA-2C, the M-1A

incorporates sliding filters which band-limit the system

response under full-power conditions. This has the effect

of discriminating for vocal information in the signal to

increase clarity, and is particularly useful when sound

pressure levels are high. It is recommended that subwoof-

ers be used with the system if it must pass the full audio

frequency range at all times. The preferred choice of

subwoofer for the UPA-2C is the Meyer Sound USW-1.

M-1A Control Electronics Unit

UltraSeries™ M-1A

Power

Sense Limit

Safe

Adj

Lo Cut

Cal

VHF

Var

Safe ∞

10 843

Attn dB

+ -

VHF