Hifisonix ‘Symphony’ Line Preamplifier

I designed and built this preamplifier while living in Taiwan a few years ago. The Symphony preamp features Baxandall tone controls, up to 7 inputs,  a class A 2 W headphone amplifier and a Goldpoint 24 position attenuator.  The write-up describes the design process and choices in some detail and my listening impressions: Part 1 […]

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Small Signal Audio Line Stage Buffer/Headphone Amplifier

This design, which I completed in 2010, takes an LM4562 and marries it to a hefty single ended class A output stage, which can be biased up for either 50 mA or 110 mA. The output stage is included in the global feedback network and can achieve 1 ppm at 20 kHz  into 600 Ohms […]

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