Warranty Information

This product is warranted for parts and labor from the date we ship it. Check with the factory authorized distributor in the country you are purchasing this product for specific warranty information.

Distributors are only required to offer warranty service on Pass products that they have sold. They are not obligated to offer warranty repair for products purchased from other distributors. Products purchased from other distributors should be returned to the country of purchase for warranty repair.

Supersymmetry: What it is, Where it came from, How it works, Why bother

(theory and philosophy by Pass that you can ignore)

Supersymmetry is the name given to a new type of amplifying circuit, which operates quite differently than the designs presently appearing in literature and the marketplace. I have been designing new amplifiers all my adult life, and patented several of them, but I regard this particular idea as the most interesting and profound. The name “supersymmetry” describes the circuit but is also the name of a theory from the field of particle physics that considers the ultimate nature of matter and forces in terms of symmetries.

A little history of the development of this idea might help to illuminate the concept. As far as I’m concerned, the progress in amplifier design has to do with making amplifiers better while making them simpler.

Numerous amplifier design techniques have been offered during this century, but the ideas that have stood the test of time have delivered much better performance in simple ways. Two of the best ideas have been negative feedback and push-pull operation. Negative feedback is a simple technique, which requires only a couple more parts, arranged simply, but it achieves dramatic improvements in performance. Similarly for push-pull operation, a couple more parts delivers incredibly greater efficiency and improved distortion at high power levels.

The concepts of negative feedback and push-pull operation in amplifiers were old enough in 1970 that some of their limitations were becoming apparent, at least with regard to audio amplifiers. In the hands of mediocre designers, feedback was often overused to cover up design sins elsewhere in the circuit, with the result that the amplifier did not sound very good, in spite of good distortion measurements. Push-pull circuits, while allowing high efficiency and cheap manufacture, did not improve the character of the sound at lower levels, where we do most of our listening, a deficiency which designers often use feedback to cover up.

It appears that the human sense of hearing is more subtle in some ways than distortion measurement apparatus, and many audiophiles were dissatisfied with the results of the new breed of solid state amplifiers appearing in the 60’s and 70’s. These designs used lots of feedback to clean up their efficient push-pull circuits.

The innovative designers were beginning to consider some variations of and alternatives to these tried and mostly true approaches, and some new designs appeared.

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Pass Labs X250 owner manual Warranty Information
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X250 specifications

The Pass Labs X250 is a distinguished power amplifier that showcases the brand's commitment to delivering high-quality audio performance, blending robust engineering with innovative technology. Known for its exceptional build quality and sonic capabilities, the X250 is designed for audiophiles and music enthusiasts who demand the best from their audio equipment.

At its core, the X250 is a Class A/B amplifier, which means it combines the efficiency of Class B with the superior sound quality of Class A. This hybrid design allows the amplifier to deliver high power output while maintaining low distortion levels, resulting in a clean, dynamic sound that captures the essence of the original recording. The amplifier delivers 250 watts into 8 ohms and 500 watts into 4 ohms, making it suitable for driving a wide range of loudspeakers with ease.

One of the standout features of the X250 is its use of Pass Labs' proprietary “Bias Current” technology. This innovative system optimizes performance by ensuring that the output devices operate in their most linear region, reducing crossover distortion and enhancing the amplifier's overall sound quality. This results in a more accurate and natural reproduction of audio, appealing to listeners who seek fidelity above all else.

Another notable characteristic of the X250 is its impressive dynamic range. The amplifier is designed to handle transient peaks with confidence, preserving the impact and nuance of musical passages, whether it's the delicate pluck of a guitar string or the thunderous notes of a full orchestra. The low noise floor further enhances the listening experience, allowing even the quietest details to be heard clearly.

The build quality of the X250 is equally impressive, featuring a rugged chassis and high-grade components that ensure durability and reliability. With its elegant appearance, the amplifier is not only a functional piece of equipment but also an attractive addition to any audio setup. The attention to detail in the design is evident, with a focus on minimizing vibrational interference and maintaining signal integrity.

In conclusion, the Pass Labs X250 is a remarkable power amplifier that combines advanced technology with exceptional sound quality. Its Class A/B design, Bias Current technology, and high power output make it a versatile choice for a wide range of audio applications. For those who value both performance and aesthetics, the Pass Labs X250 stands out as a superb option in the realm of high-fidelity audio amplification.
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