GENERAL

The Shure Model 545L unidirectional dynamic micro- phone is a low-impedance unit designed for instrument or voice pickup in public address applications. With its attached cable, the microphone is suitable for mounting on an optional A25B swivel adapter, on a fixed pipe or flexible gooseneck, or for handheld use.

The 545L is ideal for use in critical public address sys- tems such as those used in political conventions and legisla- tures, hotels, public auditoriums, stadiums, and churches. The microphone has an exceptionally uniform pickup pattern that provides an excellent solution to feedback problems in reverberant locations, permits best utilization of space in small studios, facilitates orchestral placement, and provides effective rejection of unwanted noises.

Features

SEffective cardioid pickup pattern, uniform to low fre- quencies, minimizes reverberation and feedback, discriminates against pickup of nearby performers and extraneous noise

SExcellent reproduction of music and voice

SShock-mounted cartridge for quiet operation

SLow impedance for unlimited cable length

SProvided with very flexible, small diameter shielded cable

SRugged and dependable under all operating conditions

SPECIFICATIONS

Type

Dynamic

Frequency Response

50 to 15,000 Hz (see Figure 1)

TYPICAL FREQUENCY RESPONSE

Figure 1

Polar Patern

Cardioid (unidirectional)—uniform with frequency, symet- rical about axis (see Figure 2)

Impedance

Microphone rating impedance is 150 Ω (250 Ω actual) for connection to microphone inputs rated at 75 to 300 Ω

Phasing

Positive pressure on diaphragm produces positive voltage on BLACK cable lead (see Figure 3).

Dimensions

See Figure 4

CARTRIDGE

INTERNAL CONNECTIONS

FIGURE 3

Sensitivity (at 1,000 Hz)

Open Circuit Voltage: – 57.5 dBV/Pa* (1.3 mV) *(1 Pa = 94 dB SPL)

Cartridge Shock Mount

Internal rubber vibration isolator

CABLE

6.1 m (20 ft) two-conductor shielded, attached, small diam- eter cable

Case

Silver finish aluminum and ARMO-DURR with stainless steel screen

OVERALL DIMENSIONS

Figure 4

Net Weight

354 grams (12–1/2 oz)

GOOSENECK MOUNTING

To mount the 545L on a gooseneck or fixed pipe with a 5/8”–27 thread, unscrew (turn counterclockwise) the end cap at the cable end of the microphone, and remove the end cap and strain relief by sliding them down the length of the cable. Fish the cable through the gooseneck or pipe and firmly thread the microphone to the mount.

OPTIONAL ACCESSORIES

Swivel Adapter. . . . . . . . . . . . . . . . . . . . . . . . . . . . A25B Line Matching Transformer . . . . . . . . . . . . . A95 Series Gooseneck (12 in., 18 in.) . . . . . . . . . . . . . . . G12, G18 Windscreen . . . . . . . . . . . . . . . . . . . . . . . . . A2WS-GRA

REPLACEMENT PART

Cartridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . R45L