Pass Labs X250 owner manual d the differential distortion with supersymmetry

intrinsic matching between the circuits, (c) the distortion of each half with supersymmetry, and

(d) the differential distortion with supersymmetry.

On this curve (B) we can clearly see that intrinsic symmetry due to the matching of the two halves reduces the distortion by a factor of 10. Supersymmetry (D) creates a more perfect match, and results in an additional reduction by a factor of 10. However there is essentially no difference in the distortion figures at the output (C) of each half of the circuit considered alone. Supersymmetry does not work by reducing the distortion per se, rather it works to precisely match the two halves of the circuit and lets the balanced output ignore the unwanted components. As long as the two halves are matched, this performance tends to be frequency independent, and does not deteriorate over the audio band. With mid-level distortion figures on the order of .002%, this is very high performance for a single balanced gain stage.

The following pages include, a typical distortion curve of the amplifier, a list of specifications for the amplifier, and where to reach us.

If you have questions, or we can help you, please feel free to contact us. Again, you can easily contact Nelson Pass by email addressed to nelson@passlabs.com, and you are welcome to ask questions or offer comments. Other personnel are available through the website www.passlabs.com, as are copies of patents, DIY articles, and product information.

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