Meridian America 557 User Manual

Background

Meridian have maintained a strong reputation for their power amplifier technology for over 15 years. Until now, their power amp developments have concentrated on high-transparency low-power models or on the custom amplifiers in their renowned active and digital speaker designs.

Meridian 557

The 557 takes the Meridian 500 Series into new territory – with 200W of clean clear power – for the first time allowing the option of a complete Meridian front end for large passive speakers. The Meridian 557 can be used with the 502 or 501 preamps, or with a Meridian DSP Surround Processor.

The Meridian 557 houses two powerful amplifiers in a dual mono construction. The amplifiers are both rated at 200W into 8 ohms. Each over-specified output stage uses 8 high-power transistors. These, combined with a massive lownoise 1.6kVA toroidal transformer, permit this amplifier to deliver currents in excess of 30A, ensuring no loss of performance even into loads that dip below 2 ohms. The massive power delivery of this amplifier makes it ideal for driving difficult loudspeaker loads.

557 can be operated in bridged mode giving power in excess of 680W into 8 ohms, 1000W into 4 ohms.

The 557 provides balanced and unbalanced inputs as well as twin outputs for bi-wiring.

The topology of 557 is very much in the Meridian tradition. A high-precision fast DC-precise input stage is combined with a fully complementary amplification and output stage. Also, the 557 uses Meridian’s well established self -adjusting bias and error-correction output topology.

The 557 is fully protected against DC and thermal overload. A proprietary Meridian soft-start circuit is also fitted.

557

Stereo Power Amplifier

Sales information 1st December 2001

• Dual-mono 200-watt design

• Balanced and unbalanced

inputs

• Massive low-noise 1.6kVA

toroidal transformer

• Current delivery of over 30A

into difficult loads below 2 ohms

• Fully protected against DC and

thermal overload.

• Soft start using proprietary

Meridian circuit

Meridian Audio Limited

Stonehill, Stukeley Meadows Huntingdon Cambridgeshire PE29 6EX

T +44 (0) 1480 445678 F +44 (0) 1480 445686

Meridian America Inc.

Suite 122, Building 2400 3800 Camp Creek Parkway Atlanta GA 30331

T (404) 344 7111 F (404) 346 7111

www.meridian-audio.com

Technical Specification

Power output: 200W into 8 ohms

680W into 8 ohms Bridged 1000W into 4 ohms Bridged

Distortion: <0.05% Signal/Noise: –90dB Inputs: Balanced on XLR – Sensitivity 3.00V rms (2.21V rms bridged).

Unbalanced on phono – Sensitivity 1.44V rms (1.34V rms

bridged).

Outputs: Twin outputs for bi-wiring. Construction: Two-channel dual-mono construction – Stereo and Bridged.

4 pairs of output devices per side. 4 high quality smoothing capacitors per side. Error corrected output stage. Idealised magnetic circuit design. Dynamic bridge front end gives fully balanced input operation. Fully protected against DC and thermal overload. Soft start using proprietary Meridian circuit.

Dimensions: 174mm (6.85in) H, 385 (15.16) W, 306 (12.05) D. Weight 27kg (60lbs) Controls: Rear-panel controls for Power On/Off, Bridge/Stereo Mode. Front display: Power indicator lamp.

557