SONY VFET AMP SERIES

This stresses the power supply during the turn-on surge, but also could result in a short across the capacitors when the originals died.Д«ecause of this ampвЂ™s construction, the capacitors are also used to hold the power supply board in place. This is definitely not a best practice: the original old capacitors (bottom, black, with screw terminals) are still electrically in circuit, with 10000 uF more capacitance paralleled across them. The last shop before me did a paralleling of capacitors. This amplifier used screw terminals on the back В the owner asked for binding posts on the Speaker A terminals.

SONY VFET AMP SERIES

They replaced the bias diodes with 1N4148s in series for reliability, and replaced nearly all the capacitors. Very fortunately, the previous shop did mostly good work. ThereвЂ™s a set of diodes in the power amplifier circuit used to establish bias which often go bad for, more or less, no reason and destroy the 2SK60/2SJ18 VFET finals which are quiteВ difficultВ to locate, and cannot be replaced with any other kind of semiconductor. They feature ultra low distortion, although not a huge amount of power, but are known for being touchy. They were only made for a couple years, and Sony never made any other VFET amplifiers. These VFET amplifiers were an experimental branch of SonyвЂ™s amplifier line-up. He had it sent to my shop for an inspection and a few minor upgrades to ensure it will work reliably and safely once heвЂ™s received it. This Sony TA-4650 was shipped to me from Canada for a shop visit on its way to its ultimate owner in California, who just bought it on eBay.

Sony vfet amp