4th Aug 2023 : we are now delivering with ripple eater 2.0 boards. Starting from 7 Nov 2018 , the boards are delivered with gold-plated metal surface. This is a PSU PCB designed by Andrew C Russell of hifisonix.com. The PSU board is particularly designed for his class A amplifier sx and kx-amplifier. Of course other class A amplifiers would be greatly benefit with this PSU board too. The design is a capacitor multiplier ( which is also called ripple eater by JLH). According to designers note, the design can provide ripple rejection of 65dB@100Hz and 85dB@10KHz. This allows the amplifier to have an extremly quite background, when properly implemented. The full documentation can be found in Andrew's hifisonix website. We are authorized by the designer to manufacture and sell his boards. Boards dimension : PSU board : 103.5mm x 79mm PCB thickness : 1.6mm Copper thickness : 75um( 4 times standard thickness) Surface finishing : Gold-plated with solder resist coated on both side for best reliability. The construction guide ( in pdf format) can be downloaded from hifisonix website. We do air shipping worldwide at US$6.00. We welcome combine shipping. Powered by SoldEazy