Stereo 250w Reference Power Amplifier
Meridian's most powerful reference two channel amplifier has been designed and built to deliver the best possible Hi-Res performance from any high-quality passive loudspeaker system. Bridgeable to over 1.5Kw, the 857 features a totally new design for a Meridian power amplifier, borne out of extensive research, experience and a thorough understanding of psychoacoustic principles.
Effortless power delivery of 500W per channel into four ohms and bridgeable to >1.5kW mono into four ohms.
Low-feedback construction provides ultra-low distortion, ensuring an unparalleled level of clarity and transparency across the audible range.
Balanced and unbalanced inputs are provided, with unbalanced inputs converted to balanced before they enter the amplifier using Meridian’s proprietary ‘Superbal’ technology.
Designed to operate in thermally hostile environments, including in-rack when the dedicated Meridian 857 rack mount variant is specified.
When in standby mode, a standing voltage is maintained, meaning that optimum performance can be achieved almost immediately after switching the Meridian 857 on.
As well as balanced and unbalanced inputs, the Meridian 857 is bridgeable via a Bridge Mode Selector switch and also includes a trigger input [3.5mm 5-30 VDC]. In addition, the power amplifier can be bi-wired to a pair of passive loudspeakers via the featured WBT output terminals.TECHNOLOGIESERROR CORRECTION AND LINEARITY
The open-loop characteristics of an amplifier are crucial to its sound quality. The 857 design is intrinsically linear and uses error correction in the output stage to provide low open-loop output impedance. This allows the 857 to achieve impeccable measured performance and a high damping factor while only applying modest amounts of negative feedback. ‘SUPERBAL’
The use of shunt feedback to eliminate common mode distortion is well known. Meridian’s proprietary ‘Superbal’ circuitry brings this advantage to the balanced input, while also converting unbalanced signals to balanced as they enter the amplifier.CONSTRUCTION
Includes five secondary transformer windings for maximum isolation between low power and high
power parts. A ground plane design has also been used for optimal signal handling, while WBT output terminals have been provided to allow bi-wiring.
• Multilayer circuit boards – ensure the best electromagnetic performance
• New linear supply – for isolation from AC supply and increased durability and sound quality.
• Non-ferrous chassis and panels – aluminium construction for magnetic linearity
• 250W RMS into 8 Ohms per channel both channels driven
• 500W RMS into 4 Ohms per channel both channels driven
• Bridgeable to >1KW RMS into 8 Ohms
• Bridgeable to >1.5KW RMS into 4 Ohms
• 4 WBT terminals per side allow bi-wiring
• Two XLR balanced inputs
• Two RCA unbalanced inputs
• Trigger input [3.5mm 5-30 VDC]
• High level of passive cooling for silent in-room running
• Six variable speed fans maintain amp functionality if hostile thermal conditions encountered in rack
• Backlit touch sensitive logo changes colour to indicate amplifier’s status
• ‘Standby’ [BLUE], ‘Normal Operation’ [GREEN]’, ‘Fans Active’ [AMBER], ‘Overload’ [RED]
• Advanced linear power supply: 100V ac 50/60 Hz | 110-120V ac 50/60Hz | 220-240V ac 50/60Hz
• HEIGHT: 175mm (4U high in-rack), WIDTH: 480mm, DEPTH: 411mm
• WEIGHT: 32kg
• Black finish in aluminium and glass
• Dedicated rack mount variant (4U high)
• Custom Meridian Select colours also available