Jean Hiraga's Super Class-A Amplifier

Dan has completed a follow-up project to the Jean Hiraga - "Le Monstre" 8W Class-A Amplifier that he built back in July 2008. Impressed with the result of the 8W Hiraga, Dan set his sights to another Jean Hiraga design - the bigger "Super Class-A 30W" which also had previously appeared in the French magazine "L'Audiophile".


The original driver transistors were used, but seeing that the original power transistors are no longer available, Dan opted for Toshiba 2SA1943 and 2SC5200 transistors. The new transistors allowed the use of a higher rail voltages (35V vs 24V), resulting in a measured power output of 58W of Class-A power.


The amplifier enclosure was constructed using aluminum channels and plates. As one would expect with a Class-A amplifier delivering this much power, the heat sinks are huge and so is the power supply (500VA transformer and 1.2 Farads of filter capacitors.


Dan reports good sonic results from this amplifier. "Jean Hiraga's deceptively simple and pure circuit topology once again shines through. The sound seems effortless and gives the impression of a much higher power amplifier yet still being able to produce all the low level details, the sound which Class-A is renowned for."

For full details of Dan's project, see the Jean Hiraga's Super Class-A Amplifier project page.


Additional DIY Solid State Audio Projects:

• Dan's Jean Hiraga - "Le Monstre" 8W Class-A Amplifier
• Mark's Single-Ended 2SK1058 MOSFET Amplifier

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