Up for sale is my treasured Manley tube line stage / pre-amplifier that rivals many higher end brand. Manley Control Master Line Preamplifier uses 12AT7 and 12AU7 for each channel and it sounds much better than modern day 12AX7 based preamplifier. It has both RCA and XLR input and outputs. Ive recapped all the electrolytic capacitors with the best audio grade capacitors made by Nichicon and Panasonic a few years ago for better noise rejection since I used this preamp with very high efficient and high sensitivity speakers. I also installed / replaced the audio signal coupling capacitors with Mundorf Silver / Old / Gold and Silver / Gold capacitors for better natural tone in the audio path. I also added AC Ground Lift Switch to isolate the Ground Path in the event of noisy ground line in the AC power line. The two balance trim pots in the front of this preamp is really neat and never been used in other preamp design. It allows the user to adjust the feedback from full feedback to very low feedback to alter the sonic to suit your system and also acts for the perfect balance between the left and right channel. There are many more small improvements such as better resistors and other upgrades that I done to improve the sonic and transparency to another level from the stock unit. However, the circuit is the same as the Original Manley Labs design with no modifications to the sound. I also have the original hand drawn Manley Labs schematic for this preamplifier that I will send along with the unit. Please ask questions you have. My asking price is fair so please dont send LOW Ball offers. Thanks!