For sale is Pass DIY B1 passive preamp with significant upgrades. PRP and Dale resistors, Mogami wire throughout, Auri Caps, and an AMB Labs Sigma 11 regulated power supply. Please see the AMB Laboratories and Pass DIY website for further details. There was well over $450 invested in this project. I am asking $350 plus shipping which does not even cover the parts purchased. It will ship via USPS Priority with delivery confirmation and insurance. I accept USPS Money Order only. Please check my feedback and PM with questions. I have many more photos if you are serious about the purchase. Thanks!