This tube preamp is based on the famous Matisse circuit, some modifications have been applied to expand the range of frequency, it sounds smooth and punchy. It"s built up with 2 PCBs, the thickness of the lower main circuit PCB is 2mm which can avoid damage when replacing tubes, the upper PCB is for shielding and protection, excellent design! Features * Components: Selected 6N3 tube, Panasonic high voltage capacitors, special ordered high voltage out-couling capacitors, 1% tolerance metal film resistors, quality sealed mini potentiometers. * Glass fiber golden board, red solder mask, with green LEDs on the bottom of the tubes which give a fascinating looking in the dark! * The kit is prewired and well set, you can use it directly even without a case * Overall Dimension (including posts, front knob and RCA sockets): 125mm(length) x 115mm(width) x 73mm (thickness) * Approx. 3 times amplifier. Note: The DIY kits need professional experiences. Need you attention when installing the output lines of the transformer. The final result depends on your operation.