Dennis Hui

Miscellaneous Projects

Please find enclosed some pictures of an A30 I completed five months ago. This is my first completed amplifier project. It was a great learning experience and I'm very happy with how it turned out. As a novice DIYer, I stuck fairly close to the A30 schematics. The output devices used are IRFP044's since I already have a supply on hand. The power supply uses a 500VA 2x20V transformer and four 62000uF capacitors in a CRC configuration. The rails are at +/-25V. The PCB's used are based on Mark Finnis' designs (Thanks Mark!) and the 11" X 11" R-theta heatsinks were obtained through a group buy. Having listened to the amplifier for a few months, I find it to be very musical. Compared to my previous amplifier, music on the A30 seems more three-dimensional, with the midrange and treble taking on greater clarity and delicacy. The bass is perhaps a bit more plumb, but not unpleasantly so. I'm grateful to Mr. Pass for sharing with us his wonderful designs and his tremendous support to the DIY community. And many thanks to Mr. Pass and the other members of who provided much technical guidance, inspiration and encouragement. Cheers, Dennis Hui

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