Details：

ZERO-ZONE PRT-12A preamplifier reference - American Gary CARY-SLP90 circuit, the circuit sound with High details, medium and low frequency very thickness. PRT12A uses one-point grounding, quiet back without noiseHigh-voltage power supply uses Toshiba K2700 FET as a high-voltage power supply adjustment Transistor.The filament power supply uses a single-input and double-out voltage regulation mode to supply power to the left and right channels respectively. High-voltage filtering uses Hitachi electrolytic capacitors, chemical high-voltage decoupling capacitors, Taiwan's 3W 1% precision metal film resistors, silver-plated ceramic tube holders, SPRAGUE and MKP coupling capacitors, and has a good price/performance ratio. PCB size: 155x177x1.6MM FR4 Work voltage: 0-220V AC >=30mA (200-220V are all ok) 0-14V >=0.8A (AC12-AC15V are all ok)Tube model：4pcs 12AU7 tubes （default price not included tubes）

Note：

This is bare pcb ，not included any parts ！

Transformer link：

//www.aliexpress.com/item/4000833832126.html

Assembled board ，just for reference：