ElectroVoice® MTH-2.5/42BT Manifold Technology® Mid-bass/High-Fre­ quency Sound Reinforce­ ment System • Sonically improved lower midrange • 40° x 20° constant-directivity pattern • Smaller MT trapezoidal enclosure • Rotatable MB & HF horns • High acoustic output, low distortion • Manifold Technology® enables smaller and lighter arrays • MT systems with different coverage patterns and output capabilities may be mixed and matched • Unique rigging scheme for flexible array design and quick assembly SHOWN WITHOUT GRILL • Available without rigging hardware

SPECIFICATIONS Third Harmonic, MTH-2.5/42BT is an active, two-way, horn­ Frequency Response (measured in far 200 Hz: 0.8% loaded, 40° x 20° constant-directivity system field, calculated to one meter on axis, 1,000 Hz: 1.3% with a trapezoidal enclosure, utilizing two high­ swept sine wave, one watt into mid-bass 3,000 Hz: 0.1% power mid-bass drivers in the mid-bass fre­ section, anechoic environment; see 10,000 Hz: 1 .4% quency band and two high-power compression Figure 1): Transducer Complement, drivers in the high-frequency band . Both the 150-20,000 Hz MB: Two DL 1OX 10-inch drivers, mid-bass and high-frequency horns may be Recommended Crossover Frequencies: 40° x 40° fiberglass horn rotated in the enclosure. This configuration 160 Hz, 1,600 Hz HF: Two DH1A variant compression results in remarkably high acoustic output from Efficiency, MB/HF: drivers; HP42S, 40° x 20° horn a small enclosure. The MTH-2.5/42BT may be 16/25% Impedance (see Figures 2 & 7), combined with other members of the MT-2B Long-Term Average Power-Handling Nominal, MB/HF: and MT-4B loudspeaker family. The combina­ Capacity (per ANSI/EIA 426-A 1980; see 8/8 ohms tion of the MTH-2.5/42BT loudspeaker system Power Handling Section), Minimum, MB/HF: and the MTL-2B low-frequency loudspeaker MB/HF: 600/150 watts 4.917.2 ohms system form the MT-2/64B full-range system. Maximum Long-Term Average Mid-Band Input Connections: There are two models in the MTH-2.5/42BT Acoustic Output: Two Neutrik Speakon® NL4MP series: the MTH-2.5/42BTCF (carpeted fini 3h 130 watts Enclosure Materials, Structural, All with flying hardware), and the MTH-2.5/42BTC Sensitivity (SPL at one meter, indicated Versions: (carpeted finish without flying hardware). input power, anechoic environment, band­ 14-ply birch plywood limited pink-noise signal), MB/HF: Finish: The MTH-2.5/42BT mid-bass section utilizes 111 Watt: 105.5/116 dB Black carpet two high-efficiency, low-distortion DL 1OX 6001150 Watts: 133.5/138 dB Hanging: 10-inch mid-bass drivers coupled to a unique Beamwitlth (angle included by 6-dB-down Two-point flying system (tracks accept phase plug (U.S. Patent No. 4,718,517). An points on polar responses, indicated one­ New Haven NH 32102-1 fittings) Aperiodic Enhancer™ , this phase plug extends third-octave bands of pink noise; see Dimensions, the upper-end response by making use of the Figures 3 and 4), Height: 91.4 cm (36.00 in.) fact that only the apex area of the cone near the 900-20,000 Hz, Horizontal: Width at Front: 57.2 cm (22.50 in.) voice coil is in motion at the higher frequencies, 40° (+20°, _5°) Width at Back: 28.3 cm (11.13 in.) and automatically adjusts the acoustic loading 900-20,000 Hz, Vertical: Depth: 75.9 cm (29.88 in.) to maximize acoustic output. The output of the Side Angles: 15° each (30° wedge) 20° (+36°, _3°) four drivers is summed through a mid-bass Net Weight: Directivity Factor R. (Q), 800- to 20,000-Hz manifold (U.S. Patent No. 4.923,021) and 93.0 kg (205 Ib) Median (see Figure 5): coupled to a 40° x 20° constant-directivity horn. Shipping Weight: 31 .6 (+43.3, -16.0 ) The square mid-bass horn may be rotated to Directivity Index D;, 800- to 20,000-Hz 97.5 kg (215Ib) tailor the directionality of the system to match Median (see Figure 5): specific acoustic requirements. 15.0 dB (+3.5 dB, -3.1 dB) DESCRIPTION Distortion, 120 dB SPL at 1 Meter, Shaped The Electro-Voice MTH-2.5/42BT mid-bassI The MTH-2.5/42BT high-frequency section con­ Spectrum (see Figure 6), high-frequency loudspeaker system is a mem­ tains two modified DH1Amt-16 compression Second Harmonic, ber of the family of Manifold Technology® MT drivers manifolded onto a 40° x 20° constant­ 200 Hz:2.5% loudspeaker systems designed for high-level directivity horn. The modified DH1Amt-16 1,000 Hz: 1.4% sound reinforcement in -sound touring (1 .375-inch bolt-on version of the DH1 A, with a 3,000 Hz: 1.4% and permanent-installation applications. The modified magnetic structure) features a power- 10,000 Hz: 2.5% MTH-2.S/42BT SPECIFICATION GRAPHICS

FIGURE 1 - Axial Frequency Response FIGURE 4 - Beamwidth vs. Frequency -HO 120 0. i:

100 I I I~ I I I IIII I

I-HF Wi III ::Ii 31.5 f\ ::0: ~r. 0 / \... l...<' 0 W -HORIZONTAL 0 0 '" V\...,.. v I)\... z 10 / \ \'\r 1ft.,., *VERTICAL' A < '-V\.. , c MB- 1\ r-- ...... ,. ,- W -\. i-.r'- ../ Il. ~ FREQUENCY IN HERTZ-- - ~ 3.16

FIGURE 5 - Directivity vs. Frequency

FREQUENCY IN HERTZ

FIGURE 3 - Polar Response

FREQUENCY IN HERTZ ~.,.,."~.' ,.' ~ ~.,.. 1251-k ,.. -250Hz . 1M' -100Hz FIGURE 6 - Harmonic Distortion 130

to" W ~'to" 120 , ' , ..' 1 " "\ 110 FUNDAMENTAL ! "."IItf ! 10' •I . lit' I 1I •· ,.. 1 kHz . '10' 2 kHz . 110" 4 kHz - - - 100

, 11C,.... l1li" .. 50 I IIII \If ...... :"'.,'" 2030 50 100 200 500 1000 2000 5000 10000 20000 '10" 125Hz ,... 250Hz ,.. 500Hz .' - . - . - FREQUENCY IN HERTZ 2nd HARMONIC __ 3rd HARMONIC ......

.•.-~~ FIGURE 7 - Wiring Diagram · ,..,. -1 kHz ~~110' 2kHz 1111" 4kHz

HF (' OHMS NOM.)

. - ... 2, D-"CG"'R"'E"'E"'N------'------'''''''='''' 110' ,kHz ,... 1I11dtz. RED RED ·tIt"'e'"5 dB PER· - . - HORIZONTAL--- 1. OIVISION VERTICAL---

MB R..-JOHMS (I OHMS NOM.) ·long box axis vertical 1, l BLACK BLACK ful motor structure and titanium diaphragm for in an anechoic environment using a swept sine­ CROSSOVER, EQ AND SIGNAL maximum linear acoustic output, extended high­ wave signal. The Dx34digital electronic unit was The usable frequency ranges of the individual frequency response and accurate transient re­ used to provide the necessary crossover filters, MTH-2.5/42BT sections are 150-2,000 Hz for sponse. The outputs of the two drivers are and signal delay. No high-pass the mid-bass section and 1,200-20,000 Hz for summed through the MTA-22 high-frequency crossover filters were applied to the low end of the high-frequency section. Crossoverfrequen­ manifold (U.S. Patent No. 4,629,029) and the mid-bass section. One watt of power (2.83 cies of 160 and 1,600 Hz with 24-dB-per-octave coupled to an HP64S hom. The HP64S is a volts rms at 500 Hz) was applied to the mid band slopes are recommended. For full-range appli­ member of the HP TransPlanar™ horn series of the mid-bass section. The sound pressure cations, one of the MTL-2B low-frequency loud­ (U.S. Patent No. 4,685,532) that features level was normalized for an equivalent one­ speaker systems is recommended for use with beam width-control vanes as part of the meterdistance. the MTH-2.5/42BT. For optimal acoustic perfor­ waveguide to correct the very-high-frequency mance, the Electro-Voice Dx34 digital elec­ beamwidth anomalies that typically plague DIRECTIVITY tronic crossover/equalization/signal-delay unit 2.0-inch-throat horns. The square high­ The directional response of the MTH-2.5/42BT is recommended. frequency horns may be rotated to tailor the was measured in an anechoic environment at a directionality of the system to match specific distance of 6.1 meters (20 feet) using 1/3- The Dx34 is a programmable, two-in/four-out acoustic requirements. octave filtered pink noise. A full spherical mea­ digital electronic unit which may be configured surement system was used. The Dx34 digital for stereo two-way, mono three-way plus All versions of the MTH-2.5/42BT are constructed electronic unit was used to provide thE) neces­ , or mono four-way operation. Each of 0.75-inch thick, 14-ply birch plywood and are sary crossover filters, equalization and signal output section includes crossover filters, equal­ extremely well braced to survive the rigors of the delay. The polar response of the loudspeaker ization, limiting, signal delay, polarity and gain road. The MTH-2.5/42BTCF (flying) and MTH- system at selected 1/3-octave frequencies is adjustment; the parameters of which all may be 2.5/42BTC (nonflying) systems are covered with shown in Figure 3. The frequencies selected programmed and stored by the user. In the black Ozite Super TNT carpeting, the most rug­ are fully representative of the polar response of mono three-way configuration, the Dx34 in­ ged in the industry. The the system. The beamwidth of the system utiliz­ cludes a factory preset for optimal performance MTH-2.5/42BTCF system incorporates a two­ ing the complete 1/3-octave polar data is shown ofthe MT -2/42B loudspeaker system (the MTH- point flying system. All models feature a black in Figure 4. The directivity factor (0), R., and 2.5/42BT and MTL-2B systems combined) that nylon cloth grille. directivity index, D" are shown in Figure 5. utilizes Linkwitz-Riley 24-dB-per-octave cross­ Complete AcoustaCADDTM data is available for over filters at 160 and 1,600 Hz. Each output APPLICATIONS the MTH-2.5/42BT loudspeaker system. section has equalization specifically matched The MTH-2.5/42BT is ideal for any professional to the loudspeaker system, and signal delay set concert-sound touring or permanent­ DISTORTION to achieve zero lobing error and time alignment installation application requiring high sound Distortion for the MTH-2.5/42BT (shown in Fig­ between frequency bands. In addition, the out­ pressure levels with low distortion from a com­ ure 6) was measured on axis in the far field in an put levels of each frequency band are set so pact enclosure. The Manifold Technology® de­ anechoic environment with an input signal that that, with the output level controls set in the sign maximizes the acoustic output per enclo­ would result in a sound pressure level of 120 dB zero-dB position, the loudspeaker system will sure frontal area, acoustic output per enclosure at one meter. The Dx34 digital electronic unit have a flat frequency response in an anechoic bulk volume, and acoustic output per enclosure was used to provide the necessary crossover environment when used with having weight of the loudspeaker system. This en­ filters, equalization and signal delay. A 24-dB­ identical gain. ables loudspeaker arrays to be constructed per-octave high-pass crossover filter at 160 Hz J that are significantly smaller and lighter than was applied to the low end of the mid-bass ELECTRICAL CONNECTION would be obtainable with conventional loud­ section. A frequency spectrum typical of close­ AND SYSTEM WIRING speaker systems. The MTH-2.5/42BT may be miked was employed. The sound Electrical connections to the MTH-2.5/42BT are combined with other members of the MT -2B and pressure level was normalized for an equiva­ made on the back of the enclosure via a 4-pin MT-4B loudspeaker family, providing the array lent one-meter distance. Plots of second- and connector. There are two connectors on the designer a variety of coverage angles, acoustic third-harmonic distortion are shown referenced input panel to allow paralleling of other MTH-2.5/ output and enclosure sizes from which to choose. to the fundamental. 42BT systems. The Neutrik Speakon®NL4MPR For full-range applications, the MTH-2.5/42BT is used for both connections. One mating may be combined with any of the MTL-2B or POWER-HANDLING CAPACITY Neutrik Speakon®NL4FC cable-end connector MTL-4B low-frequency sound reinforcement sys­ Electro-Voice components and systems are is supplied with each loudspeaker system. Th," tems. (The MTL -2BT is a low-frequency system manufactured to exacting standards to ensure pin assignments are as follows: with a trapezoidal enclosure that is dimension­ reliability in continuous use in arduous real-life ally identical tothe MTH-2.5/42BT.) Foroptimal conditions. Besides utilizing industry-standard Pin 1+: MB (+) Pin 1-: MB (-) acoustic performance of the MT loudspeaker power tests, extreme in-house power tests Pin 2+: HF (+) Pin 2-: HF (-) systems, the Electro-Voice Dx34 digital elec­ which push the performance boundaries of the troniccrossover/equalization/signal-delay/limiter are also performed for an extra The mid-bass section has two 8-ohm drivers; unit is recommended. measure of reliability. The MT systems are however, the acoustic loading of the phase rated per the EIA Loudspeaker Power Rating plugs and horn increases their electrical imped­ Careful attention was paid to details to provide Full Range (ANSI/EIA RS-426-A 1980), which ance to a nominal 16 ohms each. These two both the touring company and sound contractor uses a shaped random-noise signal to simulate drivers are wired in parallel, resulting in a single a convenient and time-saving sound reinforce­ typical music to test the mechanical and thermal 8-ohm nominal load connected to Pins 1+/1-. ment package. The MT-2B dimensions were capabilities of the loudspeakers. The Dx34 digi­ The high-frequency section has two 16-ohm chosen for efficient truck pack and high-density tal electronic unit was used to provide the neces­ drivers wired in parallel, resulting in a single 8- array design. The systems may be stacked sary crossover filters and equalization during ohm nominal load connected to Pins 2+/2-. A three high and four wide (or four high and three power testing. Specifically, the MTH-2.5/42BT wiring diagram of the loudspeaker system is wide) in a standard truck box, enabling 12,000 passes the ANSI/EIA 426-A power test with the shown in Figure 7. The electrical impedance watts of sound system to be accommodated in following test parameters: versus frequency is shown in Figure 2. only three feet of truck-floor length. The two­ point rigging system offers flexible array design Mid-bass Section: FL YING THE MT SYSTEMS A manual entitled the MT Flying Manual is and efficient assembly. To facilitate service, a P EIMAX): 600 watts variety of screws, washers and hex key Test Voltages: 45.5 volts rms available from Electro-Voice, and is included wrenches are provided with each loud­ 91.0 volts peak with each flying MT loudspeaker system. A brief speaker system. In addition, there are wiring 3.45 ohms each input introductory overview is included here. The MT diagram labels in convenient locations inside Flying Manual should be consulted for com­ the enclosure. High-Frequency Section: plete structural specifications and detailed in­ P EIMAX): 150 watts formation on safely suspending and using the FREQUENCY RESPONSE Test Voltages: 30.2 volts rms MT systems. The MTH-2.5/42BT frequency response (shown 60.4 volts peak The MTH-2.5/42BTCF (carpeted) is the version in Figure 1)was measured on axis inthe far field RSA (1.15xRE): 6.100hms of the MTH-2.5/42BT loudspeaker system that label for the high-frequency section located on chase. If such malfunction occurs during the includes flying hardware. The MT systems in­ the H F-driver support shelf near the drivers. specified period, the product will be repaired or corporate a unique two-point flying system that Note that, when replacing the mid-bass and replaced (at our option) without charge. The permits a wide range of vertical angle adjust­ high-frequency horns, special care must be product will be returned to the customer pre­ ment, and offers maximum flexibility in array taken to locate the rear flanges of the horns into paid. Exclusions and Limitations: The lim­ design and implementation for both touring the sealing gaskets. The screws securing the ited Warranty does not apply to: (a) exterior sound and permanent installations. The quick­ horns should be firmly tightened, but not over­ finish or appearance; (b) certain specific items release, aircraft L-track-type hardware design tightened. As a service convenience, a hard­ described in the individual product-line allows arrays of loudspeakers to be assembled ware kit that includes 1/8-inch and 5/32-inch statement(s) below, or in the individual product (and disassembled) very quickly, and offers hex-key wrenches and an assortment of spare data sheet or owner's manual; (c) malfunction such flexibility in the vertical angling of cabinets screws and washers are included with every resulting from use or operation of the product that pull-up points are usually unnecessary. MTH-2.5/42BT loudspeaker system. other than as specified in the product data Furthermore, all of the flying MT-2B and MT-4B sheet or owner's manual; (d) malfunction re­ loudspeaker models include the same rigging Failure of the 10-inch mid-bass driver will re­ sulting from misuse or abuse of the product; or hardware, allowing the different models to be quire the entire driver to be returned to an (e) malfunction occurring at any time after re­ mixed as necessary throughout an array. authorized Electro-Voice service center for re­ pairs have been made to the product by anyone pair. A high-frequency-driver failure can be other than Electro-Voice or any of its authorized The rigging track accepts New Haven NH 321 02- repaired in the field by replacing the diaphragm service representatives. Obtaining Warranty 1 type double-stud ring fittings. Individual rig­ assembly; or, if desired, the entire driver can be Service: To obtain warranty service, a cus­ ging points have typical break-strength ratings returned to an authorized service center for tomer must deliver the product, prepaid, to of 3,750-4,000 pounds, which translates to repair. The following service parts are available Electro-Voice or any of its authorized service working-load ratings of 750-800 pounds for a from the Service Department in Buchanan, representatives together with proof of purchase 5:1 safety factor. (ConsulttheMTF/yingManua/ Michigan: of the product in the form of a bill of sale or for specific structural strength ratings and limi­ receipted invoice. A list of authorized service MTH-2.5/42BT Service Data Sheet: #532484 tations.) The enclosures may be oriented with representatives is available from Electro-Voice HF: #81138-XX 16-ohm DH1A Diaphragm Kit the rigging track on the sides of the enclosure, at 600 Cecil Street, Buchanan, MI491 07 (6161 #827-1431 Modified DH1Amt-16 Driver or on the top and bottom, and may be daisy 695-6831 or 800/234-6831). Incidental and MB: #810-1491 DL10XDriver chained together as long as the safety factor is Consequential Damages Excluded: Product 5:1 or greater, and local regulations are met. repair or replacement and return to the cus­ Electro-Voice offers a line of flying-hardware ARCHITECTS' AND ENGINEERS' SPECIFICATIONS tomer are the only remedies provided to the accessories for use with the MT loudspeaker customer. Electro-Voice shall not be liable for systems. The loudspeaker system shall be a two-way active mid-basslhigh-frequencysystem. The mid­ any incidental or consequential damages in­ cluding, without limitation, injury to persons or CAUTION: The MT loudspeaker systems bass section shall operate from 150-2,000 Hz property or loss of use. Some states do not should be suspended overhead only in ac­ with a sensitivity of 105.5 dB for one watt at one allow the exclusion or limitation of incidental or cordance with the procedures and limita­ meter, and consist of two 1O-inch cone drivers, consequential damages so the above limitation tions specified in the MT Flying Manual and each individually coupled to a mid-bass phase or exclusion may not apply to you. Other Rights: manual update notices. plug, then collectively manifolded and coupled to a 40° x 20° constant-directivity horn, have a total This warranty gives you specific legal rights, ROTATING THE HORNS input impedance of 8 ohms, and have a power and you may also have other rights which vary To rotate the mid-bass and high-frequency rating of600 watts as per ANSI/EIA426-A 1980. from state to state. horns, turn the enclosure face up and remove The high-frequency section shall operate from Electro-Voice Speakers and Speaker Sys­ the grille using a #2 Phillips screwdriver. Re­ 1,200-20,000 Hz with a sensitivity of 116 dB for tems are guaranteed against malfunction due move the screws securing the two horns using one watt at one meter, and consist of two com­ to defects in materials or workmanship for a a 1I8-inch hex-key wrench, lift the horns and pression drivers coll3ctively manifolded and period of five (5) years from the date of original rotate 90°. Lower the horns back into the enclo­ coupled to a 40° x 20° constant-directivity horn, purchase. The Limited Warranty does not apply sure, making sure that the rear flanges of the have a total input impedance of 8 ohms, and to burned voice coils or malfunctions such as horns are correctly seated. Special care must have a power rating of 150 watts as per cone and/or coil damage resulting from improp­ be taken to locate the rear flanges of the horns ANSI/EIA 426-A 1980. The overall system shall erly designed enclosures. Electro-Voice active into the sealing gaskets. Replace all screws have a uniform on-axis frequency response from electronics associated with the speaker sys­ that secure the front flange of the horns. The 150-20,000 Hz, and shall have a nominal hori­ tems are guaranteed for three (3) years from screws should be firmly tightened, but care zontal beamwidth of 40° and a nominal vertical the date of original purchase. Additional details should be taken not to overtighten. beamwidth of 20°. The loudspeaker system shall are included in the Uniform Limited Warranty have a trapezoidal enclosure with 15° angled statement. FIELD SERVICE sides forming a 30° wedge, shall be constructed In the unlikely event that the MTH-2.5/42BT from 0.75-inch thick, 14-ply birch plywood, shall Electro-Voice Flying Hardware(including en­ should require service, both the mid-bass and be finished with a black carpet, shall have a black closure-mounted hardware and rigging acces­ high-frequency drivers can be accessed from nylon grille, and shall have a two-point rigging sories) is guaranteed against malfunction due the front of the enclosure by removing the grille system that will accept New Haven 32102-1 or to defects in materials or workmanship for a using a #2 Phillips screwdriver, and the horns 32111-1 type double-stud ring fittings (if appli­ period of one (1) year from the date of original using a 1/8-inch hex-key wrench. The mid­ cable). The loudspeaker enclosure shall be 36.00 purchase. Additional details are included in the bass manifold assembly can be removed from inches high, 22.50 inches wide atthe front, 11.13 Uniform Limited Warranty statement. the enclosure after removing the two screws on inches wide at the back and 29.88 inches deep, Electro-Voice Accessories are guaranteed the back of the enclosure (below the input and shall weigh 205 pounds. The loudspeaker panel), and the drivers can be unbolted from the against malfunction due to defects in materials system shall be the Electro-Voice MTH-2.5/42BT or workmanship for a period of one (1) year from mid-bass manifold using a 5/32-inch hex-key (MTH-2.5/42BTCF or MTH-2.5/42BTC). wrench. There is a wiring diagram label for the the date of original purchase. Additional details are included in the Uniform Limited Warranty mid-bass section located on the bottom of the UNIFORM LIMITED WARRANTY statement. enclosure near the drivers. The high-frequency Electro-Voice products are guaranteed against drivers can be unbolted from the manifold using malfunction due to defects in materials or work­ Service and repair address forthis product: Electro­ a 5/32-inch hex-key wrench. In addition, the manship for a specified period, as noted in the Voice, Inc., 600 Cecil Street, Buchanan, Michigan high-frequency-driver diaphragms can be re­ individual product-line statement(s) below, or in 49107 (616/695-6831 or 8001234-6831). placed through the top handle holes using a #2 the individual product data sheet or owner's Phillips screwdriver. There is a wiring diagram manual, beginning with the date of original pur- Specifications subject to change without notice. IEt I ELECTRO·VOICE a MAR. IV company 600 Cecil Street, Buchanan, Michigan 49107 MANUFACTURING PLANTS AT • BUCHANAN, MI • NEWPORT, TN • SEVIERVILLE, TN • OKLAHOMA CITY, OK • GANANOQUE, ONT. ® © Electro-Voice, Inc. 1996 • Litho in U.S.A. Part Number 533193 - 9607