Three Years of Refinements Help the Multi-Chassis Xs-300 and Xs–150 Amps, First in the Series, Sound Subjectively as Beautifully as They Measure
INTERNATIONAL CES 2012, LAS VEGAS, Jan. 10, 2012 — Pass Labs introduces the Xs-300 and Xs–150 Amplifiers, first entries in a new generation of Xs Series amplifiers, at CES 2012, beginning here today.
The new amps are designed to measure well objectively and, equally important, sound subjectively as well as they measure, an exacting engineering challenge that has led to a multitude of ear-pleasing refinements. Pass Labs’ new enhancements further narrow the gap between what scientific measurements report about amplifier performance and what the human ear subjectively hears.
The Xs-300 and Xs–150 Amplifiers are monoblock models delivering 300 and 150 watts, respectively. Both models employ double-stacked chassis, with the power supply and current source in one chassis and the input and main output stage in the other chassis. The separate power supplies enable a bounty of benefits, including lower electromagnetic noise, twice as much storage capacitance as earlier Pass Labs amps, banks of high-speed/soft-recovery rectifiers, improved high-frequency noise filters, bigger and better transformers, improved passive decoupling, massive heat sinks, and lower standby currents.
The Xs Series has been three years in development. The first year, Pass Labs settled on the power supply and physical package. The second year, Pass Labs finalized the output stage and front end. The third year, the company refined the front end and the biasing of the output stage.
In the process, Pass Labs applied a number of new refinements, including adjusting the values for push-pull Class A biasing and the amount of single-ended bias in the output stage. It also significantly increased the single-ended bias in the output stage over earlier Pass Labs amplifiers. All three changes delivered major improvements. Pass Labs also installed sturdy output stage transistors, with a combined capacity well over 10 KW, and massive heat sink assemblies capable of 2 KW all day long.
The Xs-300 and Xs–150 Amplifiers will be available 1st Quarter 2012 from authorized Pass Labs dealers at suggested prices of $85,000 and $65,000 per pair (U.S. MSRP), respectively.
About Pass Labs
Founded in 1991 by legendary audio designer Nelson Pass, Pass Laboratories, Inc. markets its unique amplifiers, preamplifiers and speakers throughout the world. The company has been based in Foresthill, California, since its beginning, and is widely regarded as one of the most innovative audio brands in the world. Its critically acclaimed Aleph, X and XA-Series products have won numerous awards, and Founder and CEO Nelson Pass holds numerous audio patents. His achievements include developing the first dynamically biased Class A amplifier circuit, developing a fully cascode audio power amplifier, and developing the Stasis amplifier in 1977. He helped popularize solid-state, single-ended Class A power amplifiers, and developed the very successful Aleph series of products, and the Super-Symmetryâ„¢ circuit, which achieves exceptionally low distortion and noise levels.
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