At the heart of Meyer Sound's EXP line of cinema products is the Acheron high-performance screen channel loudspeaker. Optimized for installation behind perforated screens, the two-way loudspeaker combines the advantages of self-powered technology and innovative horn design to deliver exceptional, precise coverage for the left, right, and center sound channels for cinema.
The Acheron loudspeaker is available in two full-range models: the Acheron 100, with a 100-degree horizontal by 50-degree vertical horn, which is ideal for wide theatres; and the Acheron 80, with an 80-degree horizontal by 50-degree vertical horn, which is suitable for more narrow theatres and re-recording stages.
The Acheron horn (patent pending) was specifically designed for cinema use and features a very soft roll-off outside the extremely well behaved coverage angle. The horn is fixed within the enclosure to ensure an accurate acoustic crossover, phase response, and an incredibly consistent vertical pattern between the low and high frequencies. The Acheron’s 580 Hz crossover point places most of the dialog in the horn, which is ideal for cinema applications.
Boasting a frequency response of 38 Hz to 17 kHz at ±4 dB, as well as a generous peak output of 139 dB with very low distortion, the Acheron stands up to the most demanding of digital soundtracks, maintaining a wide dynamic range and full fidelity. Designed and manufactured at Meyer Sound's headquarters in Berkeley, California, the Acheron's drivers include one 15-inch low-frequency neodymium magnet cone driver and one high-frequency 4-inch diaphragm compression driver. The drivers yield uncompromising quality and full bandwidth, making the Acheron suitable for small and medium theatres, re-recording stages, and production and postproduction facilities.
The Acheron's sophisticated onboard amplifica-tion produces consistent and predictable results in any system design. The proprietary Meyer Sound power amplifier is a two-channel, class AB/H amplifier with complementary MOSFET output stages that yields a total output of 1685 W (3370 W peak). Built-in signal processing includes an electronic crossover and correction filters — to achieve a flat phase and frequency response — along with driver protection circuit-ry. The self-powered design not only ensures consistent results but also simplifies installation in both new and existing rooms.
The optional RMS™ remote monitoring system allows comprehensive monitoring of system parameters on a Windows®-based computer.
Strategically placed 3/8-inch threaded points on the side corners of the Acheron cabinet allow the unit to be fixed to floors with uptilt or downtilt using optional mounting brackets. The Acheron can also be mounted on top of the Acheron LF loudspeaker, also with uptilt or downtilt, using optional stacking brackets.
- Exceptional fidelity and extended highfrequency performance
- Constant-Q horn yields uniform response throughout the coverage area
- Extraordinarily flat amplitude and phase response for tonal accuracy
- Wide horn coverage available for larger, wider rooms with the Acheron 100
- Narrow, focused coverage available for smaller rooms with the Acheron 80
- Seamless integration with the Acheron LF loudspeaker and HMS-10 surround loudspeaker
- Small to medium-sized theatres
- Larger theatres with use of Acheron LF
- Re-recording stages
- Production and postproduction studios
|Operating Frequency Range
||37 Hz – 18 kHz
||38 Hz – 17 kHz ±4 dB
||700 Hz – 17 kHz ±30°
|Maximum Peak SPL
80° horizontal x 50° vertical
100° horizontal x 50° vertical
||One high-power 15" cone driver with neodymium magnet
Nominal impedance: 4 Ω Voice coil size: 4"
Power handling: 1200 W (AES)
||One 4" compression driver
Nominal impedance: 8 Ω Voice coil size: 4"
Diaphragm size: 4"
Exit size: 1.5"
Power handling: 250 W (AES)
||Differential, electronically balanced
|Maximum Common Mode Range
||±15 V DC, clamped to earth for voltage transient protection
||Female XLR input with male XLR loop output
||10 kΩ differential between pins 2 and 3
||Pin 1: Chassis/earth through 220 kΩ, 1000 pF, 15 V clamp network to provide virtual ground lift at audio frequencies
Pin 2: Signal +
Pin 3: Signal –
Case: Earth ground and chassis
||None on input, DC blocked through signal processing
||>50 dB, typically 80 dB (50 Hz – 500 Hz)
||Common mode: 425 kHz; Differential mode: 142 kHz
||Integral to signal processing (<80 kHz)
|Nominal Input Sensitivity
||10 dBV (3.2 V rms, 4.5 V peak) continuous is typically the onset of limiting for noise and music
||Audio source must be capable of producing +20 dBV (10 V rms, 14 V peak) into 600 Ω to produce the maximum peak SPL over the operating bandwidth of the loudspeaker
||Complementary MOSFET output stages (class AB/H)
1125 W low channel
560 W high channel
||3370 W peak
|THD, IM, TIM
||4 Ω low channel
8 Ω high channel
||Forced air cooling, twointernal fans (one ultra lowspeed fan, one reserve fan)
||250 V NEMA L6-20 (twistlock) inlet or IEC 309 male inlet
|Automatic Voltage Selection
||Automatic, two ranges, each with high-low voltage tap (uninterrupted)
|Safety Agency Rated Operating Range
||95–125 V AC; 208–235 V AC, 50/60 Hz
|Turn-on and Turn-off Points
||85–134 V AC; 165–264 V AC
Max. Long-Term Continuous Current (>10 sec)
Burst Current (<1 sec)9
Ultimate Short-Term Peak Current
|0.71 A rms (115 V AC); 0.38 A rms (230 V AC); 0.79 A rms (100 V AC)
5.8 A rms (115 V AC); 2.8 A rms (230 V AC); 6.3 A rms (100 V AC)
6.4 A rms (115 V AC), 3.2 A rms (230 V AC), 7.2 A rms (100 V AC)
26 A peak (115 V AC), 14 A peak (230 V AC), 28 A peak (100 V AC)
7 A peak (115 V AC), 7 A peak (230 V AC), 10 A peak (100 V AC)
|RMS Network (Optional)
||Equipped with two-conductor twisted-pair network, reporting all operating parameters of amplifiers to system operator’s host computer
||31.00" w x 35.00" h x 20.50" d (787 mm x 889 mm x 521 mm)
||173 lbs (78.47 kg)
||Premium birch plywood
||Low gloss, black textured
||3/8" threaded points on side corners for optional bracket adapters, which allow the Acheron to be mounted to floors with uptilt or downtilt, as well as on top of the Acheron LF (also with uptilt or downtilt)