Sx80t two-way speaker system with transformer – Electro-Voice SX80T User Manual

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Sx80T T

-W

ay Speaker System W

ith T

ransformer

Sx80T Two-Way Speaker System With Transformer

but protects the tweeter from long-term

power extremes that would normally destroy

the tweeter.

Enclosure Construction

The Sx80T enclosure is contructed of very-

durable High-impact polystyrene that is hard

to dent, scratch, or break. This enclosure

allows for molded in attachment points for

the optional Sx80MB mounting bracket

or for use with an OmniMount® Series

75 mounting system.

The enclosure is paintable to match any de-

cor. It is recommended, however, that a small

area should be tested with the desired paint

in order to ensure that there are no adverse

effects and that the paint has sufficient ad-

hesion. Care should be taken not to get paint

onto the woofer cone or into the horn throat.

Frequency Response

The combination of a 203-mm (8-inch)

woofer, a wide-bandwidth high-frequency

driver and an equalized crossover results in

the wide and smooth overall response shown

in Figure 1. This response was measured at

1 meter (3.281 feet), using a 2.83-volt swept

sine-wave input in a full-space anechoic

chamber using the internal passive crossover.

No external equalization was used.

Figure 1 also shows the half-space measure-

ment of the Sx80T loudspeaker. This curve

gives an indication of how the system will

respond when mounted on a wall, which is a

likely application. This response was also

measured at 1 meter (3.281 feet), using a

2.83-volt swept sine-wave input using the

internal passive crossover. No external

equalization was used.

Connections

The Sx80T is equipped with barrier strip

connectors with a cover. Care should be

taken to ensure that the correct polarity is

observed when connecting the Sx80T. The

barrier strip is marked with + for positive

and - for negative.

Constant-Directivity Speaker System

The crossover frequency and speaker com-

ponent geometries have been selected so that

the directional characteristics of the woofer

and constant-directivity high-frequency horn

match at the crossover frequency to create a

special system type, the constant-directivity

system. At higher frequencies the horizon-

tal coverage pattern remains constant and the

vertical pattern smoothly transitions to a 90°

angle above 5,000 Hz. Response within the

90° x 65° rated coverage angle is uniform,

which means dependable audience coverage

without “hot spots” or dead zones at certain

frequencies. The 90° x 65° dispersion char-

acteristic also helps avoid early reflections

from nearby floor or side-wall surfaces which

could degrade performance. The controlled

directivity of the high- and low-frequency

transducers also eliminates response irregu-

larities caused by diffraction off nearby en-

closure edges and, in combination with an

essentially flat on-axis frequency response,

produces a total acoustic power output that

is uniform with frequency.

Directivity

A unique feature of the Sx80T is the con-

stant-directivity dispersion provided by the

90° x 65° horn. The polar response of the

system at selected one-third-octave band-

widths is shown in Figure 2. These polar

responses were measured in a full-space

anechoic environment at 6.1 meters (20 feet)

using one-third-octave pink-noise inputs.

The frequencies selected are fully represen-

tative of the polar response of the system.

Beamwidth of the system utilizing the com-

plete one-third-octave polar data is shown

in Figure 3. Directivity factor, R

and di-

rectivity index, D

, are plotted in Figure 4.

Power-Handling Capacity

Electro-Voice components and systems are

manufactured to exacting standards, ensur-

ing they will hold up, not only through the

most rigorous of power tests, but also

through continued use in arduous, real-life

conditions. The EIA Loudspeaker Power

Rating Full Range (ANSI/EIA RS-426-A

1980) uses a noise spectrum which mimics

typical music and tests the thermal and me-

chanical capabilities of the components.

Electro-Voice will support relevant addi-

tional standards as and when they become

available. Extreme, in-house power tests,

which push the performance boundaries of

the woofers, are also performed and passed

to ensure years of trouble-free service.

Specifically, the Sx80T passes ANSI/EIA

RS-426-A 1980 with the following values:

= 6.21 ohms (1.15 x R

)

= woofer DCR = 5.4

E(MAX)

= 175 watts

Test voltage = 32.97 volts rms,

65.93 volts peak (+6dB)

The “peak” power-handling capacity of a

woofer is determined by the peak test volt-

age amount. For the Sx80T, a 65.93-volt

peak test voltage translates into 700-watts

short-term peak power-handling capacity.

This is the equivalent of four times the “av-

erage” power-handling capacity, and is a

peak that can be sustained for only a few mil-

liseconds. However, this sort of short dura-

tion peak is very typical in speech and mu-

sic. Provided the amplifier can reproduce

the signal accurately, without clipping, the

woofer will also perform accurately and re-

liably, even at these levels.

Service

In the unlikely event the Sx80T requires ser-

vice, the woofer can be removed from the

front. The high-frequency driver can be re-

moved by separating the front and the rear

halves of the enclosure and removing the bolt

that attaches the driver to the rear. A service

data sheet is available from Electro-Voice.

Suspending Sx80T Enclosures

WARNING: Suspending any object is po-

tentially dangerous and should be attempted

only by individuals who have a thorough

knowledge of the techniques and regulations

of rigging objects overhead. Electro-Voice

strongly recommends that the Sx80T be sus-

pended taking into account all current na-