Shure SR112B, SR116B User Guide

222

HARTREY AVE.. EVANSTON,

IL.

60204

U.S.A.

DATA

AREA

CODE

TWX:

312/866-2200

910-231.0048

CABLE:

SHUREMICRO

TELEX:

72-4381

OPERATION AND SERVICE INSTRUCTIONS

SHEET

MODEL SR112B AND SR116B

SPEAKER SYSTEMS

MODEL SR112B SPEAKER SYSTEM

FIGURE

DESCRIPTION

The Shure Model SR112B and SR116B Speaker Systems are compact, rugged, heavy-duty, two-way units. They are designed for use with Shure Model similar high-power amplifiers in studio monitor, night club or other applications requiring a small, wide range speaker system. When properly installed and connected,

SR112B and SR116B will provide outstanding per-

the formance in critical applications due to their wide frequency response, low distortion, and smooth dispersion characteristics. The Speakers have a nominal impedance of 8 ohms and are designed to operate with amplifiers

capable of delivering up to 100 watts to an 8-ohm load. They can be used either direct-coupled or with a constant-voltage 25-volt line, or 70-volt line using a Shure A1 02A Transformer.

Quality sound reproduction is achieved through the use of two 8-inch heavy-duty speakers and a high-frequency driver coupled to a 120" radial horn. The front-ported

bass reflex design of the enclosure provides cy enhancement. A built-in series-type passive crossover network provides 6 dB per octave frequency speakers and 18 dB per octave rolloff for the high-frequency driver. A four-position attenuator switch allows high-frequency level adjustments of -4, -2,

and

dB.

The SR112B (see Figure 1) is a weather-resistant unit, and is designed for permanent installation either indoors or in a protected outdoor environment such as under the

roof of an open pavilion. Adhesives used in the

are moisture-resistant, and trim and fastening hardware

have a high corrosion resistance.

SR116B is a portable unit (see Figure 2), and is de-

The signed for temporary installation either indoors or in a

rolloff for the low-

SR105 or

low-frequen-

SR112B

MODEL SR116B SPEAKER SYSTEM

FIGURE

protected outdoor environment. The SR116B is supplied with a 15m (50 ft), 18-gauge, rubber-jacketed connecting cable with locking phone plugs, and a black vinyl grille cover. The corners of the protectors. A retractile handle and balanced design contribute to ease of transporting.

and covered in black, scuff-resistant, textured vinyl. The attractive black sculptured fabric grille is rugged, cleanable, and replaceable if damaged. The radial horn and baffle board assembly is ruggedly constructed of resistant thermoplastic resin. Molded feet protect surfaces and permit stacking.

their own feet, or in a tilted position using an appropriate support. The Shure Wall Mount Swivel Bracket provide for tilting on a horizontal surface or wall or ceiling mounting. A slip-on protective cover (Model

units are constructed of 15.9 mm

Both

SR112B and SR116B may be operated vertically on

The

A112A Tilt Bracket and the A112D

A112C) is also available.

SR116B are equipped with steel

(5h

in.) wood,

SPECIFICATIONS

. . .

. .

Power Rating

Power Load for

Constant-Voltage

Operation Impedance Frequency Response . .45 Crossover Frequency

High-Frequency

Attenuator

. .

. . .

. .

Maximum recommended ampli-

fier output to 8 ohms: 100 Watts continuous, 28 Vrms, 48V peak

. . .

.78 watts (25-volt input, 8 ohms)

. . .

.8 ohms nominal (see Figure

,2600 Hz; high frequency: 18 dB/

. .

.2 dB steps (+2 to - 4)

16 kHz (see Figure 4)

octave 6

rolloff; low frequency:

dB/octave rolloff

shock-

27Al631

1980.

(TG)

Shure Brothers

inc.

Printed

U.S.A.

.""

POLAR CHARACTERISTIC

18V

400

1111

.00

In21

1 I 1

1111

101

ATTENUATION SWITCH

40 60

100

ZOO

FREQUENCY

TYPICAL IMPEDANCE CURVE

FIGURE

100

FREWENCY IN HERTZ

lW0 10,000 20,000

LEGEND

-----

2000

TYPICAL POLAR PATERNS

FIGURE

TYPICAL FREQUENCY RESPONSE

FIGURE

Sound Pressure

Level (SPL) EIA rating: 48 dB at 9.2m (30 ft)

........

from 1

milliwatt, equivalent to 97 dB at lm (3.3 ft) with 1watt input

Total Harmonic

Distortion

..........

Less than 2% at 1 kHz [meas-

ured at 1.2m (4 ft) and 106 dB SPLI

Phasing (Polarity)

Positive voltage on plus

.....

(+)

minal (SR11B) or phone jack

tip (SRll6B) produces pos-

itive sound pressure

High-Frequency

Section .120° radial horn

Horizontal Distribution

Vertical Distribution

...........

...

120" (see Figure 5)

90"

Directivity Factor

(Q)

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

.6.9 at 2 kHz full octave measure-

ment

Environmental:

Operating

.....

Temperature

7" to 43°C (20" to 110°F)

Storage

Temperature

Humidity

.....

...........

29" to 71 "C (-20" to 160°F)

SR112B: Moisture-resistant SR116B: Normal indoor/outdoor

Connectors

..........

SR112B: One 2-screw terminal

strip

SR116B: Two parallel-wired

phone jacks

Overall Dimensions

...

,400 mm H x 584 mm W x 381

mm D (15% in. x 23 in. x 15 in.)

Weight

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

SR112B: 17.71 kg (39 Ib) SR116B: 18.61 kg (41 Ib)

Construction 15.9 mm

.........

in.) wood, black vinyl covering, black fabric grille.

SR112B: All surfaces (internal

and external) and all components treated for weather resistance

SR116B: Contains handle and

steel corner protectors.

Supplied Accessories

SR116B: 15m (50 ft) heavy-duty

cable with locking phone plugs; grille cover

ter-

Optional Accessories

A1 12A Tilt Bracket

A1 12C Protective Cover A1 12D Wall Mount Swivel Bracket A102A 70-Volt Transformer

INSTALLATION

General

In planning a sound system using the SR112B or SR116B Speaker System, carefully observe the horizontal (120") and vertical (90") sound distribution of the units. Maximum coverage for source-oriented installations is generally obtained with Speakers on each side of the sound source and as far forward as possible, with each Speaker tilted slightly either downward (for wall- or

mounted units) or upward (for floor-standing units). The angle of tilt (assuming a single Speaker to either side of the sound source) should be such that an imaginary line from the center axis of the Speaker runs to the back row

of the audience area. The Shure

Figure 6) provides complete freedom in the vertical

direction and the

provides up to

A112D Wall Mount Swivel Bracket

50" downward tilt and a horizontal pivot

angle of 60 degrees in both directions (see Figure 7). For "clustered" installations covering a wide area, each Speaker should be positioned so that its angle of cover-

age overlaps with that of the Speaker next to it as their sound output enters the audience area.

A112A Tilt Bracket (see

ceiling-

SRl12B SPEAKER IN A112A

BRACKET

TILT

FIGURE

SRl12B SPEAKER IN A112D WALL

MOUNT SWIVEL BRACKET

FIGURE 7

When used for distributed-speaker system, the Speakers are generally mounted at equidistant intervals throughout the area to be covered. Wall- or ceilingmounting is usually employed, although free-standing Speakers raised above head level may be used quite satisfactorily.

Of the remaining common sound installation problems, acoustic feedback can usually be dealt with by judicious Speakerlmicrophone placement, and/or the use of equalization or feedback filters in the sound system. Background noise or acoustically "dead" conditions generally require a greater volume level to maintain the proper acoustic level. However, it must be remembered that ex-

cessive volume may be intolerable to that part of the audience nearest the Speakers. In this case, or where the architectural design leaves audience areas not

reached by the main Speakers, the use of secondary or

auxiliary speaker systems should be considered. If these are used, the consideration of delay must also be faced.

Direct Amplifier Connection

The Speakers are designed to be used with power am-

plifiers having the following maximum output capabilities:

Continuous Power To:

Voltage 16 Ohms 8 Ohms 4 Ohms

Vrms 50 Watts 100 Watts 200 Watts

(48V peak)

However, sine-wave signals delivering 100 watts to a Speaker should be avoided in that they present a much greater average power than does program material. Con-

sequently, when setting up or adjusting a sound system with these Speakers, avoid the use of high-level, continuous-type test signals.

25-Volt Line Operation

The Speakers may be operated from a 25-volt line without the need for an accessory transformer. Note that when connected to a constant-voltage, 25-volt line, the Speaker will draw 78 watts.

70-Volt Line Operation

For operation from a 70-volt line, a transformer such as the Shure Model A102A provides power taps of 50, 25,

12.5 and 6 watts.

Speaker Wiring

Determine the approximate distance from amplifier to Speaker and

refer to Figure 8 to find the proper wire gauge for direct output operation. Recommended cables for the sizes listed are:

18 Gauge:

Belden #8460, #8461, #9740, #8542 16 Gauge: Belden #8470, #8471, #8472 14 Gauge: Belden #8473 12 Gauge: Belden #8477

To avoid the frequency losses, poor coverage, dead

zones, etc., resulting from improper speaker phasing in

multiple Speaker installations, all Speakers must be wired in proper polarity. The cables listed above are

colorcoded to insure that identical connections are used. Note that even common 18-gauge lamp cord (zip cord") is phased-coded with ribs along the outer jacket of one conductor.

When using the 15m (50 foot), heavy-duty cable sup-

plied with the

SRl16B Speaker, connect the right-angle

plug to a Speaker phone jack and twist the cable down-

ward behind the locking bar to prevent accidental dis-

connection. The other phone jack may be used for additional, parallel-connected Speakers.

When wiring the Speakers, consideration should be

given to positioning of the cables. While most local

electrical codes do not require locating speaker cables

in conduits or raceways, make sure that cable is placed away from hazardous traffic areas.

AMPLIFIER-TO-SPEAKER DISTANCE (FEET)

AMPLIFIER-TO-SPEAKER DISTANCE IMETERSl

200 400

50 100 150

RECOMMENDED WIRE GAUGE

FIGURE

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