Nakamichi Stasis PA-5

All pre-owned product is tested in our service department and have been passed for sale... and comes with a 90 day warranty! Fully tested to spec.

In good condition - cabinet has seen lots of wear, but this amp still ROCKS! Original Box, packing, and manual are NOT available, so this is LOCAL SALE ONLY.

See last image few images for tech details from brochure and last image are the specs.  Circa 1987-89.

An awesome powerful amp!

Tech stuff edited from Hi-Fi Classics:

The word "Stasis" displayed prominently on the amplifier's front panel is a clue that it uses circuitry designed by Nelson Pass, who is responsible for the Stasis amplifiers manufactured in the U.S. by Threshold Corporation, and licensed to Nakamichi by Threshold (Stasis is a Threshold trademark). The Nakamichi Stasis PA-5 is rated to deliver 100 watts per channel into 8 ohms; 20 to 20,000 Hz with no more than 0.1 percent total harmonic distortion.

In the words of its front-panel inscription, the Nakamichi PA-7 is an "Inherently Stable/Uniform Impedance Amplifier." A key difference from conventional amplifier circuitry is that the Stasis circuit design uses no overall ("global") negative feedback. Ordinary negative-feedback amplifiers require careful control of their phase-shift and frequency-response characteristics, as well as of the reactive component of the load impedance, in order to achieve unconditional stability. Some audiophiles have experienced amplifier oscillation, which can cause damage to the speakers, as a result of excessive load capacitance from certain speaker cables or other sources. Because the performance of the Nakamichi PA-5 is virtually independent of the load characteristics, signal dynamics, and spectral content, it is not subject to these undesirable side effects. 

The PA-5's circuit topology uses a highly linear, low-current, Stasis voltage amplifier section, operating without global feedback, in parallel with a pair of high-current output stages. These output stages, which supply the large currents needed by a speaker load, are described as positive and negative Current-Mirror Bootstraps. Although the low-power Stasis section defines the output-voltage waveform, its current output is only enough to correct for residual distortions within the Current-Mirror Bootstrap stages. The output section of each channel employs sixteen high-power transistors: fourteen connected in two groups of seven to form the positive and negative Current-Mirror Bootstraps, the other two in the Stasis amplifier section. The output-current capability is rated at 12 amperes per channel continuous or 35 amperes peak.

The Nakamichi PA-5 is a massive amplifier, with heavy heat sinks along each side and contoured handles to assist in handling its 35 pound weight. Much of its interior volume is occupied by a 450-watt toroidal power transformer and a total of 94,000 microfarads of power-supply filter capacitance. The speaker outputs on the rear panel are multiway heavy-duty binding posts that accept dual bana-na-plug connectors. The input phono jacks are gold plated. Rubber "feet" on the back of the amplifier make it possible to rest it on its back without damage to it or the supporting surface.  The only front-panel control is a large, flat plate that operates the power switch. There are no level adjustments. A green light bar above the switch serves as a pilot light, and two tiny red LED indicators near the top of the panel flash to show the onset of clipping in the left and right channels. The PA-7 is 17-1/8 inches wide, 14-1/2 inches deep, and 5-5/16 inches high. It is finished entirely in black with gold markings.