Shure 450 Series II User Manual

Model 450 Series II

User Guide

WIRING CONNECTIONS

Refer to Figure 1 and Table 1 below. For unbalanced operation, the GREEN
wire is connected to the audio input, the WHITE wire is connected to the audio
ground, and the SHIELD is connected to chassis ground. In some cases, audio
ground and chassis ground will be the same.

For balanced operation, the GREEN wire is connected to the positive audio
input, the WHITE wire is connected to the negative audio input, and the SHIELD
is connected to chassis ground.

IMPEDANCE SWITCH PRESS-TO-TALK SWITCH

GREEN

YELLOW

SHURE MODEL 450 SERIES II
PAGING AND DISPATCHING MICROPHONE

The Shure Model 450 Series II is a high output dynamic micro­phone designed for paging and dispatching applications. This
extremely rugged microphone features an omnidirectional pickup
pattern and a frequency response tailored for optimum speech in­telligibility. It also includes an impedance selection switch and a
locking press-to-talk switch.

Features

• Dual impedance

• Locking press-to-talk switch

• Rugged ARMO-DUR® base and case

• Adjustable height

PRESS-TO-TALK SWITCH OPERATION

To operate the control bar as a press-to-talk switch, simply hold
itdownandbeginspeaking.Whenyouarenishedspeaking,re­lease the control bar.

To lock the control bar in the “on” position, press it down and pull it
forward. To unlock the control bar, push it back and release it.

IMPEDANCE SELECTION

To select high or low impedance, move the impedance selection
switch, located under the microphone base, to either the HIGH or
LO position. The switch is factory pre-set to LO.

Shure recommends the low impedance setting if long lengths of
cable are used, or if severe hum is encountered. Use Shure A95
Line Matching Transformers to match a low impedance (300 W)

microphonelinetoahighimpedanceamplierinput.

BLACK

1 2 3

BLACK
RED

GREEN
WHITE

SHIELD

ORANGE

RED

HILO

GREEN

WHITE

WIRING DIAGRAM

FIGURE 1

Table 1. Typical Cable-to-Connector Wiring

INPUT TYPE WIRE

UNBALANCED

BALANCED

COLOR

GREEN AUDIO PIN 2 TIP

WHITE

SHIELD

GREEN AUDIO + PIN 2 TIP

WHITE AUDIO - PIN 3 RING

SHIELD

FUNCTION XLR

AUDIO

GROUND

CHASSIS
GROUND

CHASSIS
GROUND

CONNECTOR

PIN 3 SLEEVE

PIN 1 SLEEVE

PIN 1 SLEEVE

1/4 IN.

PHONE

JACK

NOTE: The RED and BLACK leads are not part of the audio circuit. These wires
provide a contact closure when the press-to-talk switch is depressed. This clo­sure may be used to control an external relay or a transmit/receive circuit.

CHANGING PTT CIRCUIT TO NORMALLY OPEN

Using microphones in parallel requires a normally open microphone circuit. To
modify the press-to-talk switch so that it provides a normally open circuit, proceed
as follows:

1. Remove the screws, washers, and bottom plate from the microphone.

2. Unsolder the black, red, and white leads from the terminal of the press–
to–talk switch (see Figure 1). Make sure these leads are still soldered
together. If necessary, resolder them and insulate the connection.

3. Replace the bottom plate and secure it with the screws and washers
removed in Step 1.

27C2917 (Rev. 5) Printed in U.S.A.
©2012 Shure Incorporated

SPECIFICATIONS

©2012 Shure Incorporated

Type

Dynamic

Frequency Response

200 to 5,000 Hz (see Figure 2)

TYPICAL FREQUENCY RESPONSE

FIGURE 2

Polar Pattern

Omnidirectional

Impedance (at 1,000 Hz)

HighImpedance:40,000Ω

LowImpedance:210Ω

Recommended Load Impedance

HighImpedance:100,000Ω

LowImpedance:1,000Ω

Output Level (at 1,000 Hz, Open Circuit Voltage)
High Impedance Low Impedance
–35.0 dBV/Pa* –57.0 dBV/Pa*
(17.8 mV) (1.4 mV)

*1 Pa = 94 dB SPL

Switches

Locking Press-to-Talk Switch: Activates microphone circuit and an
external relay or control circuit. The microphone circuit is normally
shorted.

Impedance Selection Switch: Double-pole, double-throw slide switch
located in the base of the microphone.

Cable

2.1 m (7 ft.) four-conductor, two conductors shielded,

non-detachable

Case

Two-tone gray ARMO-DUR



OVERALL DIMENSIONS

FIGURE 3

Net Weight

737 grams (1 lb., 10 oz.)

Shipping Weight

1020 grams (2 lb., 4 oz.)

Certication

Conforms to European Union directives, eligible to bear CE marking; meets
European Union EMC Immunity Requirements (EN 50082–1, 1992).

REPLACEMENT PARTS

Cartridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..........R96

Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...........C31C

On/Off Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...............RK141S

United States, Canada, Latin
America, Caribbean:

Shure Incorporated
5800 West Touhy Avenue
Niles, IL 60714-4608 USA

Phone: [phone]
Fax: [phone] (USA)
Fax: [phone]
Email: [e-mail]

www.shure.com

Europe, Middle East, Africa:

Shure Europe GmbH
Jakob-Dieffenbacher-Str. 12,
75031 Eppingen, Germany

Phone: [phone]
Fax: [phone]
Email: [e-mail]

Asia, Pacific:

Shure Asia Limited

22/F, 625 King’s Road
North Point, Island East

Hong Kong

Phone: [phone]
Fax: [phone]
Email: [e-mail]