Hiraga super 30W class A w/ current source + kubota reg partial assembled kit !

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This is a kit of class A amplifier with ultra-fi sonic quality. The design is with reference to the legendary design by Jean Hiraga published in L'Audiophile. This amplifier is the "Hiraga super 30W class A". With good heat dissipation, this amplifier can deliver 30W(+/-24V DC) of pure class A amplification.

Features : This is our updated and improved version. The low level section is constant current loaded, and fed by good-sounding Kubota regulator. In bench test and listening test, the amplifier has substantial improvement in speed and distortion performance in high frequency register. The noise and distortion is substantially lower. Sonically , comparing to the original design, it has a darker background, cleaner and more tranparency.

We attached some of our bench full power output measurement results in this listing.


The board is partially built with all the resistors being soldered , except the two pieces of output transistor emitter degeneration resistors.

Users are need to solder the rest of the components including the transistors, diodes, LEDs etc.
The kit features high quality components such as :
- 1% metal film resistors,
- non-inductive KOA power resistors,
- Hitachi and Toshiba hard-to-find transistors,
- hard to find Semitec constant current diodes,
- low loss silver mica caps and Wima film caps,
- On semiconductor driver transistors.
The output transistors are NOT included.
Each kit requires one pair of output transistors to be purchased elsewhere. Most of the TO-3P package transistors can be used for the output stage.
We can also provide 2% gain matched output transistors MJL4302A/MJL4281A as an option by an extra US$19.00 per kit. Please specify to buy this option during the purchase.
We provide schematic, part list and installation note for the buyers by EMAIL. We also provide heavy duty power supply boards that diyers can put in their favorite filtering electrolytic capacitors. Please check our other auctions.




PCB thickness : 1.6mm.

PCB dimension : 90mm x 97mm

Copper Thickness : 75um ( four times normal thickness !!) tin-plated.

Finishing : Double-sided tracks, double-sided solder resist coating for best reliability.

The kit contains one channel of amplifier. For stereo application two sets are needed.



We do air shipping worldwide at US$7.00.