User manual CREST AUDIO LH4 LOUDSPEAKER SPECIFICATIONS

[. . . ] LH 4 Loudspeaker TM SERIES Power Handling Full Range Continuous Program Peak LHTM4 LHTM1 LHTM2 LHTM3 LHTM5M LHTM6M LHTM7M 1, 200W 600W 1, 000W 500W 400W 500W 1, 000W 2, 400W 1, 200W 2, 000W 1, 000W 800W 1, 000W 2, 000W 4, 800W 2, 400W 4, 000W 2, 000W 1, 600W 2, 000W 4, 000W Other LH series loudspeakers Features · Optimized low frequency response · 1, 200 Watt Continuous rated power · Neutrik Speakon® input connectors · Recessed steel handles with comfortable round handgrip · Side and bottom feet for vertical or horizontal operation · Integral pole stand socket · Heavy-duty casters · High-impact resistant polypropylene cabinet corners · Heavy-gauge metal grill with black, powder-coated finish · Exterior grade 3/4", 7-ply all poplar APA-1 plywood · Scuff and weather resistant, black Hammer-HeadTM finish Description The Crest Audio LHTM4 is a low frequency reinforcement member of the Crest LHTM series. The design consists of two 18" high power woofers in an optimized vented enclosure. [. . . ] The LHTM4 cabinet is finished with Crest Audio's durable black Hammer-Head poly-coating. Polymer corners are also added to provide further protection to the cabinet. A black, powder-coated, heavygauge metal grill covers the entire front of the cabinet to protect the low woofers from unforeseen impacts. Specifications Power Handling LH 4 Loudspeaker A m plt iudeRes pons ( 1m O n- xi ) e 1W As TM There are many different approaches to power handling ratings. Crest Audio rates this unit's system power handling using a modified form of the AES Standard 21984. 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. 110 dB SPL ( e20 Pa) r 100 90 80 70 20 50 100 200 Fi e1 gur 500 1k Fr equency ( z) H 2k 5k 10k 20k I pedance m 100 50 30 20 Frequency Response This measurement is useful in determining how accurately a given unit reproduces an input signal. The frequency response of the LH4 (Figure 1) is measured at a distance of 1 meter using a 1 Watt (into the nominal impedance) sweptsine input signal. Z ( )10 5 3 2 1 20 50 100 200 500 1k Fr equency ( z) H 2k 5k 10k 20k Fi e2 gur Directivity The polar response of the LH4 is essentially omni-directional at frequencies at and below 200 Hertz. Specifications LHTM4 Loudspeaker Frequency Response, 1 meter on-axis, swept-sine in anechoic environment: Usable Low Frequency Limit (-10 dB point): Power Handling: LH 4 Loudspeaker 45 Hz to 300 Hz (±3 dB) 31 Hz Low Frequency Range: (speakers parallel, 4Ohms) 1, 200 W continuous (69. 3 V RMS) 2, 400 W program 4, 800 W peak (speakers independent, 8 Ohms) 600 W continuous (69. 3 V RMS) 1, 200 W program 2, 400 W peak TM Sound Pressure Level, 1 Watt, 1 meter in anechoic environment: Low Frequency Range: 100. 0 dB SPL, (2. 00 V input) Full Range: 129. 8 dB SPL continuous 135. 8 dB SPL peak Maximum Sound Pressure Level (1 meter): Radiation Angle measured at -6 dB point of polar response: Transducer Complement Low Frequency Section: Box Tuning Frequency: Essentially omni-directional 2x 18 in. woofer, vented basket Fbox: 41 Hz Recommended Active Crossover Frequency Region and Slope Mid Frequency - High Frequency: Impedance (Z): 90 - 120 at 12 dB/octave Nominal: 8. 0 each 7. 38 parallel Minimum: 8. 0 each 3. 69 parallel 2x Neutrik Speakon® 4 conductor input jacks, Upper woofer across 1+ & 1-, Lower woofer across 2+ & 2-. 3/4" 7-ply premium, exterior grade, all-poplar, void-free plywood. Material conforms to APA-1 specification. [. . . ] The loudspeaker system shall be a Crest Audio model LHTM4. Crest Audio reserves the right to make improvements in manufacturing or design which may affect specifications. 8/22/01 v. 1. 5 *80304809* Crest Audio Inc. Fair Lawn, NJ 07410 TEL: 201. 909. 8700 FAX: 201. 909. 8744 www. crestaudio. com [. . . ]