Shure 540SH User Guide

222 HARTREY AVE., EVANSTON, IL. 60204 U.S.A.

MICROPHONES AND

AREA CODE 3121866-2200 . CABLE: SHUREMICRO

TWX:

910- 231-0048 TELEX: 72-4381

ELECTRONIC

COMPONENTS

OMNIDIRECTIONAL DYNAMIC MICROPHONE

GENERAL

The Model 540SH SONODYNEQ impedance omnidirectional dynamic microphone with response tailoring capability at both the low and midrange-to-high frequencies.

As supplied with its extended low and high frequency response, the microphone is excellent for both music and voice in public address and recording. In addition, its tailored response provides highly intelligible speech reproduction in communications and paging applications.

540SH microphone is designed for stand mount-

The ing and has an On-Off switch on the integral

action swivel mount. Solderless impedance change, a

strong detachable cable with audio connector, rugged construction, all make the SONODYNE

Microphone Features:

Excellent reproduction of voice and music Omnidirectional pickup pattern, picks up sound all

around Response tailoring at both low and midrange-to-

high frequencies

Solderless impedance change Built-in On-Off switch, an integral part of the at-

tached, positive-action swivel assembly Rugged professional three-pin audio connector on

the microphone Strong, detachable cable especially selected for ef-

fective shielding from hum pickup Can be used indoors or outdoors, dependable under

all operating conditions

a very versatile microphone.

professional three-pin

is a dual-

positive-

MODEL 540SH

SONODYNE@ II

Polar Pattern

Omnidirectional

lmpedance

Dual. Microphone rating impedance is 150 ohms (230 ohms actual) for connection to microphone inputs rated at 19 to 300 ohms and "High" for connection to high-impedance microphone inputs. Wired for low impedance as supplied. To change impedance, see sections on lmpedance Selection and Connections.

Output Level

Open Circuit Voltage*. . . . . . . -79.0 dB

Power Level*

*O dB

**0 dB = 1 milliwatt per 10 microbars

(at 1,000 Hz)

. . . . . . . . . . . .

volt per microbar

IMPEDANCE

Low High

-55.0 dB

(.I 12 mV) (1.78 mV)

58.5 dB

SPECIFICATIONS

TY pe

Dynamic

Frequency Response

50 to 13,000

and midrange emphasis (see Figure 1)

27A1555 (TC)

1980,

Hz.

Provision for low-frequency rolloff

TYPICAL FREQUENCY RESPONSE

FIGURE

Shure Brothers Inc.

Phasing

Positive pressure on diaphragm produces positive voltage on pin on pin Figure

4.)

when connected for low impedance,

when connected for high impedance. (See

Switch

Built-in On-Off switch, integral part of swivel mount

Cable

4.6m (15 ft) two-conductor shielded, with professional three-pin female audio connector*

'Designed to mate with Cannon XL series, Switchcraft A3

equivalent connector

Case

Black and silver finish metal and black ARMO-DURQ

Dimensions

See Figure 2

(Q.G.)

Series, or

Printed in U.S.A.

23.9

05/16

IN)

OVERALL

Net Weight (less cable)

425 grams

Packaged Weight

1.07 kg (2 I b,

The Model can be tailored for low-frequency emphasis as shown in Figure phasis are desirable if the microphone is used for voice communication or in a paging system, since the tailored response enhances intelligibility of the speaking voice. The microphone is supplied with the extended low and midrange response shown in the solid line curve of Figure as follows.

A. Provide midrange emphasis:

Hold the microphone in a vertical position; unscrew (turn counterclockwise) and remove the microphone grille-cap assembly (see Figure 3).

Remove the perforated aluminum resonator plate (used for extended response); substitute the 18-hole resonator plate (supplied), and add one spacer (for a total of two).

3. Reassemble the grille-cap to the microphone, making certain that the cartridge is properly seated. Tighten securely.

B. Provide low-frequency

1. Locate the threaded hole at the back of the microphone (see Figure 3).

2. Use a small screwdriver to remove the headless No. 4-40 set screw in the threaded hole. Opening

the acoustic port produces the low-frequency

rolloff shown in Figure 1.

REsoNmod GARTwDGEJ fMcRoPHoNE cnse REAR VIEW

PLATE

(1 5 oz)

6 oz)

RESPONSE SELECTION

540SH SONODYNE@ II frequency response

1. To modify the microphone response proceed

rSTEEL SPACERS

LLE-GAP

RESPONSE

g-27THREAD"f42,1

DIMENSIONS

FIGURE 2

1. Both the rolloff and em-

rolloff:

SELECTION

FIGURE

(1-23/32 IN.)

rolloff or midrange

ACOUSTIC

OF MICROPHONE

IMPEDANCE SELECTION

The Model impedance operation. The low-impedance connection is recommended where long cable lengths are required or under conditions of severe hum disturbance. The permissible cable length is practically unlimited since neither response nor level is appreciably affected by long cables. Shure Model A95 Series Line Matching

Transformers are available for use when a

impedance microphone line is desirable but the

associated amplifier has a high-impedance input. These transformers provide a proper impedance match between a 19 to 300 ohm microphone line and a impedance input and are available with various input and output connectors.

To change the Model

ceed as follows.

1. Remove the two screws that hold the switch.

2. Gently pull the switch and its plastic housing forward out of the swivel taking care not to break any

leads.

3. With

nect the 2-terminal black plastic impedance selec-

tion socket from the back of pin 3 of the audio con-

nector. Take care not to break leads while performing this operation.

4. With the long-nose pliers, replace the impedance selection socket with pin 3 of the audio connector

inserted in socket terminal "H". Press the plastic socket firmly in place.

5. Reassemble the switch housing, switch, and

switchplate in the swivel taking care not to pinch any leads.

Fasten securely with the two previously removed

screws.

When using the microphone in low-impedance, the BLACK and WHITE cable leads are the "hot" conductors for balanced-line connections; the shield is connected to the chassis or amplifier ground.

When using the microphone in high impedance, the

WHITE cable lead is the "hot" conductor; the shield is connected to the chassis or amplifier ground. The BLACK cable lead should be insulated.

To test two microphones er phasing, connect them to an amplifier and talk or sing into them while holding them three or four inches apart. The sound from the speakers should be the same when talking into either microphone or directly between them if they are in phase with each other. If the sound drops drastically, or if a dead spot is found when talking between the two microphones, either the microphones or their cables (low impedance only) are out of phase. All cables and microphones should be tested in this manner to insure that they are in phase with each other.

To change the phase of a low-impedance microphone cable, either use a Shure terchange the wires connected to pins connector. To change the phase of a microphone,

540SH is supplied connected for low-

540SH to high impedance, pro-

long-nose pliers, lift upward and discon-

CONNECTIONS

PHASING

andlor their cables for prop-

A15PRS Phase Reverser or in-

and 3 of the

low-

high-

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