User manual CREST AUDIO LH7M LOUDSPEAKER SPECIFICATIONS

[. . . ] LH 7M Loudspeaker TM SERIES Power Handling Full Range Continuous Program Peak LHTM7M LHTM1 LHTM2 LHTM3 LHTM4 LHTM5M LHTM6M 1, 000W 600W 1, 000W 500W 1, 200W 400W 500W 2, 000W 1, 200W 2, 000W 1, 000W 2, 400W 800W 1, 000W 4, 000W 2, 400W 4, 000W 2, 000W 4, 800W 1, 600W 2, 000W Other LH series loudspeakers Features · Smooth frequency response characteristics · 500 watt continuous rated woofer · 150 watt continuous rated compression driver · 60 degree x 40 degree Constant Directivity horn with 2" throat · High power crossover components · Neutrik Speakon® connectors with automatic switching bi-amp input · Dual-angle cabinet design · Recessed steel handles with comfortable round hand-grip · Stand adapter for side-fill use · Heavy gauge metal grill with black powder-coat finish · High-impact resistant polypropylene cabinet corners · Rugged stand adapter · Exterior grade 3/4" 7-ply all Poplar APA-1 plywood · Scuff and weather resistant, black Hammer-HeadTM finish Description The Crest Audio LHTM7M is a newly designed two-way stage monitor comprised of two 12" high-power woofers, one 2" exit compression driver coupled to a 60° x 40° constant directivity horn. As with all LHTM full-range speakers, this unit can be driven in fullrange or bi-amp mode simply by plugging into the desired jack on the input plate. The LHTM7M cabinet has a dual-angle back for use in long and short throw applications. [. . . ] When high frequency drive level to the LHTM7M exceeds predetermined thresholds, the protection circuit is temporarily engaged. This subtly decreases the signal level applies to high frequency driver so that it will not be damaged due to long term overpowering. Short duration transients will not be attenuated by the protection circuit and thus have the potential to damage the driver. The protection circuit is realized through the use of a dynamically resistive component in conjunction with a switched padding circuit. An additional feature of the crossover is the use of a new switching Neutrik Speakon® connector for the bi-amp input. It is no longer necessary to manually switch, or move jumpers to reconfigure the crossover circuitry when bi-amping any of the LH series loudspeakers. This connector is wired 1+, 1- for the woofer, with 1+ being positive, and 2+, 2- for the high frequency driver, with 2+ being positive. As with the full range inputs, simply insert your Speakon bi-amp plug into the bi-amp input connector, and twist clockwise 1/8 turn. This simple action switches out the crossover, and simultaneously connects the woofer and driver directly to the bi-amp speaker cable. Specifications Power Handling 110 dB SPL (re 20 Pa) 100 90 80 70 20 LH 7M Loudspeaker Amplitude Response (1W 1m On-Axis) TM Crest Audio rates this unit's system power handling using a modified form of the AES Standard 2-1984. Utilizing audio band limited (20 Hz - 20 kHz) pink noise with peaks over four times the RMS level. This strenuous test signal assures the user that every portion of this system can withstand high impact music. The test signal contains large amounts of low frequency energy, effectively simulating the frequency content of live music situations. High frequency test signals expose the speaker system to synthesized tones that may extend beyond audibility. This rating is contingent on having a minimum of 3 dB of amplifier headroom available so as to ensure that clipping does not occur. 50 100 200 Figure 1 500 1k Frequency (Hz) 2k 5k 10k 20k Impedance Frequency Response This measurement is useful in determining how accurately a given unit reproduces an input signal. The frequency response of the LHTM7M (Figure 1) is measured at a distance of 1-meter using a 1 watt (into the nominal impedance) swept-sine input signal. 100 50 30 Z 20 ( ) 10 5 3 2 1 20 50 100 200 500 1k Frequency (Hz) 2k 5k 10k 20k Figure 2 Specifications LHTM7M Loudspeaker frequency response usable low frequency limit (-10 dB point) power handling 58 Hz to 20 kHz (±3 dB) 47 Hz LH 7M Loudspeaker TM Full Range: 1, 000 W continuous 89. 4 V RMS 2, 000 W program 4, 000 W peak passive high freq: 150 W continuous 34. 6 V RMS 300 W program 600 W peak sound pressure level Full Range 97. 0 dB SPL, (2. 83 V input) high freq107 dB SPL, (2. 83 V input) maximum sound pressure level (1 meter) Full Range High Freq 126. 8 dB SPL continuous 132. 8 dB SPL peak 134. 5 dB SPL continuous 140. 5 dB SPL peak radiation angle measured 90 degrees horizontal x 40 degrees vertical transducer complement Low Freq High Freq 1x 15" Woofer, vented basket 2. 0" Exit / 75 mm voice coil compression driver on a CD horn box tuning frequency crossover frequency (internal passive) recommended minimum active crossover Fbox 56 Hz High Freq - 1700 Hz High Freq - 1500 Hz at 12 dB/octave Low Freq Low Freq time offset Low Freq High Freq 0. 00 ms 0. 60 ms Nominal 8. 0 Nominal 8. 0 impedance Z Full Range High Freq Minimum 7. 1 Minimum 6. 8 2x Neutrik Speakon input connections 4 conductor input jacks 1x Neutrik Speakon 4 conductor biamp switching input jack enclosure materials and finish 3/4" 7-ply premium, exterior grade, all-poplar, void-free plywood. Material conforms to APA-1 specification. [. . . ] The outside dimensions shall be 30. 5 inches high by 19. 0 inches wide by 17. 0 inches deep. The loudspeaker system shall be a Crest Audio model LHTM7M. Crest Audio reserves the right to make improvements in manufacturing or design which may affect specifications. 8/22/01 v. 1. 5 *80304812* Crest Audio Inc. Fair Lawn, NJ 07410 TEL: 201. 909. 8700 FAX: 201. 909. 8744 www. crestaudio. com [. . . ]