Electro-Voice T221M User Manual

Page 2

T221M Biampable, Compact, Two-Way Floor Monitor Speaker System

“BIAMP”. The crossover is now in biamp

mode. Carefully replace the crossover and

screws. When the crossover is in biamp

mode, there is an 18-microfarad capacitor

in series with the high-frequency driver for

protection against DC voltages or amplifier

failure. This is not a crossover. It is how-

ever, protection against some forms of am-

plifier failure. An active crossover with a

crossover frequency of 1,600 Hz (1.6 kHz)

with slopes of 12 dB per octave or greater is

required. Whenever possible, a crossover

with 24-dB-per-octave slopes should be

used.

Note: The PRO

circuit is still protecting

the high-frequency driver when the system

is in biamp mode.

Connections

The T221M is equipped with Neutrik

Speakon

NL4MPR connectors. Two con-

nectors are installed in parallel, one mounted

on each end of the enclosure allowing

multiple T221M’s to be used and “daisy-

chained” together. These NL4FC connectors

are used because they are locking, self-po-

larizing and capable of 30 amps rms con-

tinuously.

Full-range pin arrangements are:

1– = IN, FULL RANGE(–)

1+ = IN, FULL RANGE(+)

2– = Not used

2+ = Not used

Biamp pin arrangements are:

1– = IN, LOW FREQUENCY (–)

1+ = IN, LOW FREQUENCY (+)

2– = IN, HIGH FREQUENCY (–)

2+ = IN, HIGH FREQUENCY (+)

If you experience any difficulty in obtain-

ing cables, connectors or wiring accessories,

the following companies can be contacted:

Neutrik USA, Inc.

1600 Malone Street

Millville, NJ 08332

Pro Co Sound, Inc.

135 E. Kalamazoo Avenue

Kalamazoo, MI 49007

Whirlwind Music Distributors, Inc.

P.O. Box 1075

Rochester, NY 14603

Power-Handling Capacity

To our knowledge, Electro-Voice was the

first U.S. manufacturer to develop and pub-

lish a power test closely related to real-life

conditions. First, we use a random-noise in-

put signal because it contains many frequen-

cies simultaneously, just like real voice or

instrument program. Second, our signal con-

tains more energy at extremely high and low

frequencies than typical actual program, add-

ing an extra measure of reliability. Third, the

test signal includes not only the overall

“long-term average” or “continuous” level—

which our ears interpret as loudness—but

also short-duration peaks which are many

times higher than the average, just like ac-

tual program. The long-term average level

stresses the speaker thermally (heat). The

instantaneous peaks test mechanical reliabil-

ity (cone and diaphragm excursion). Note

that the sine-wave test signals sometimes

used have a much less demanding peak value

relative to their average level. In actual use,

long-term average levels exist from several

seconds on up, but we apply the long-term

average for several hours, adding another

extra measure of reliability.

Specifically, the T221M is designed to with-

stand the power test described in EIA Stan-

dard RS-426A. The EIA test spectrum is

applied for eight hours. To obtain the spec-

trum, the output of a white-noise generator

(white noise is a particular type of random

noise with equal energy per bandwidth in Hz)

is fed to a shaping filter with 6-dB-per-oc-

tave slopes below 40 Hz and above 318 Hz.

When measured with an analyzer having the

usual constant-percentage bandwidth (one-

third octave), this shaping filter produces

a spectrum whose 3-dB-down points are

at 100 Hz and 1,200 Hz with a 3-dB-per-

octave slope above 1,200 Hz. This shaped

signal is sent to the power amplifier with the

continuous power set at 400 watts into the

5.98-ohm EIA equivalent impedance

(48.9 volts true rms). Amplifier clipping

sets instantaneous peaks at 6 dB above the

continuous power, or 1,600-watts peak

(97.8 volts peak). This procedure provides a

rigorous test of both thermal and mechani-

cal failure modes.

Architects' and Engineers'

Specifications

The loudspeaker system shall be a two-way,

full-range design consisting of a 305-mm

(12-inch) woofer in a vented enclosure, a

high-frequency compression driver mounted

on a 80° x 55° constant-directivity horn, and

a passive crossover/equalizer network, which

may be bypassed for use with an external

low-level active dividing network with a

corner frequency of 1,600 Hz. The loud-

speaker shall meet the following perfor-

mance criteria: frequency response of

100-16,000 Hz, –3 dB; full-range power

handling of 400 watts long term and 1,600-

watts short term with a shaped random-noise

input per EIA Standard RS-426A; low-fre-

quency power handling below 1,600 Hz in

the biamp mode of 400-watts long term and

1,600-watts short term with a shaped ran-

dom-noise input per EIA Standard RS-426A;

high-frequency power handling above

1,600 Hz in the biamp mode of 60-watts

long term and 240-watts short term with a

shaped random-noise input per EIA Standard

RS-426A; sensitivity of 101 dB SPL at 1 meter

with a 1-watt, 300- to 3,000-Hz pink-noise

input; 6-dB-down horizontal coverage angle

of 55° ±5° in the 5,000- to 16,000-Hz range;

6-dB-down vertical coverage angle of 80°

±5° in the 5,000- to 16,000-Hz range; cross-

over frequency of 2,600 Hz (electrical);

nominal impedance of 8 ohms; and mini-

mum impedance of 6.7 ohms. Input con-

nections shall be two paralleled Neutrik

Speakon

NL4MPR connectors for full-

range and biamp operation. The enclosure

shall be constructed of curved plywood,

covered with black textured paint and fit-

ted with a 16-gauge black steel grille, rub-

ber feet and a recessed carrying handle. Di-

mensions shall be 371 mm (14.62 in.) high x

594 mm (23.4 in.) wide x 406 mm (16.0 in.)

deep. Net weight shall be 22.3 kg (49 lb).

The loudspeaker system shall be the Electro-

Voice T221M.