Electro-Voice T221M User Manual

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Electro-Voice T221M User Manual

T221M

Biampable, Compact,

Two-Way Floor Monitor

Speaker System

Constant-directivity80°x55°horn with2-inchtitaniumdriver

High-output,400-watt,12-inchwoofer

Biampedorfull-rangeoperation- simplebiampinstructionsincluded insidetheenclosure

Rock-solidenclosuremadewith 12-plycurvedplywoodshell

PROTM circuitprovidesHFdriver protection

ProfessionalNeutrikSpeakon® connectorsforbiamporfull-range operation

Description

The Electro-Voice T221M is a 400-watt, twoway, high-efficiency floor monitor system. It combines professional-quality components, highlighted by the DH2T compression driver and 400-watt, high-output 12-inch woofer. The system may be biamplified or used full range with the internal passive crossover. Either way, the result is clear and articulate, high-quality sound.

The enclosure is constructed of a void-free 3/4-in. 12-ply curved plywood shell which is extremely rigid. The baffle and end pieces are made from 13-ply birch plywood. This high-strength enclosure is sprayed with a resilient, textured black finish for a truly professional appearance. The end-mounted, heavy-duty, recessed handle makes transportation easy and three rubber feet on the opposite end help keep the finish looking new.

The high-frequency section of the T221M utilizes a compact 80° x 55° constant-direc- tivity horn driven by a wide-bandwidth, two- inch-titanium-diaphragm driver. The voice coil is coupled to the diaphragm with EV’s exclusive Resonant DriveTM technology. This increases and smooths the high-frequency

response and reduces the amount of internal equalization required for flat frequency response.

EV’s self-resetting PROTM circuit is built into the crossover network to guard the compression driver from damage. If input power to the driver exceeds the nominal rating, the PROTM circuit is activated, reducing the power delivered to the driver by 6 dB. The system will remain in this mode of operation until input power is reduced to a safe level.

The optimally vented bass section of the T221M is designed using Thiele-Small parameters for efficient performance to below 100 Hz. The high-output 12-inch woofer delivers outstanding performance. It features beryllium copper lead wires with a low-mass, edge-wound voice coil and high-temperature materials. The coil is driven by a massive, 15-lb magnetic structure.

Frequency Response

The combination of a 12-inch woofer, DH2T wide-bandwidth high-frequency driver and an equalized crossover results in the wide and smooth overall response shown in Figure 2. The T221M’s axial frequency response was measured in Electro-Voice’s large anechoic

chamber at a distance of 10 feet with a swept sine-wave input of 4 volts. Figure 2 has been averaged and corrected for 1 watt/1 meter, half-space operation.

Directivity

The polar response of the T221M speaker system at selected one-third-octave bandwidths is shown in Figure 1. These polar responses were measured in an anechoic environment at 20 feet using one-third-oc- tave pink-noise inputs. The frequencies selected are fully representative of the polar response of the system. Beamwidth of the system utilizing the complete one-third-oc- tave polar data is shown in Figure 1. Rθ and directivity index (Di) are plotted in Figure 4.

Biamping

The T221M may be easily converted for biamp operation. To do this, first carefully remove the crossover. Notice the instructions on the circuit board and the four-wire “Molex” connector. The T221M comes from the factory in passive (full-range) mode. To convert the T221M to biamp operation, unplug the “Molex” connector from the header marked “PASSIVE MODE (FULL RANGE”) and plug it into the header labeled

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

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 however, protection against some forms of amplifier 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 PROTM 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 connectors are installed in parallel, one mounted on each end of the enclosure allowing multiple T221M’s to be used and “daisychained” together. These NL4FC connectors are used because they are locking, self-po- larizing and capable of 30 amps rms continuously.

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 obtaining 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 publish a power test closely related to real-life conditions. First, we use a random-noise input signal because it contains many frequencies simultaneously, just like real voice or instrument program. Second, our signal contains more energy at extremely high and low frequencies than typical actual program, adding 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 actual program. The long-term average level stresses the speaker thermally (heat). The instantaneous peaks test mechanical reliability (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 withstand the power test described in EIA Standard RS-426A. The EIA test spectrum is applied for eight hours. To obtain the spectrum, 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 (onethird 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 mechanical 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 loudspeaker shall meet the following performance criteria: frequency response of 100-16,000 Hz, –3 dB; full-range power handling of 400 watts long term and 1,600watts 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, 300to 3,000-Hz pink-noise input; 6-dB-down horizontal coverage angle of 55° ±5° in the 5,000to 16,000-Hz range; 6-dB-down vertical coverage angle of 80° ±5° in the 5,000to 16,000-Hz range; crossover frequency of 2,600 Hz (electrical); nominal impedance of 8 ohms; and minimum impedance of 6.7 ohms. Input connections shall be two paralleled Neutrik Speakon® NL4MPR connectors for fullrange and biamp operation. The enclosure shall be constructed of curved plywood, covered with black textured paint and fitted with a 16-gauge black steel grille, rubber feet and a recessed carrying handle. Dimensions 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 ElectroVoice T221M.

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