Skip to content


Your cart is empty


Subscribe to receive updates, access to exclusive deals, and more... We promise not to give your info away.

ESS (Electrostatic Sound Systems) AMP 500N Amplifier - Rare and Vintage

Sale price$0.00

Pickup currently unavailable at SkyFi 479

Ess (Electrostatic Sound Systems) Amp 500N Amplifier - Rare And Vintage Speakers

ESS (Electrostatic Sound Systems) AMP 500N Amplifier - Rare and Vintage

SkyFi 479

Pickup currently unavailable

479 South Broad Street
Glen Rock NJ 07452
United States


The ESS AMP 500N is a rare model and does not come up for sale very often.

Its even RARER in the non-metered version we have here.

Putting out an impressive 500W which is reflected by the size of the heatsinks in the back, which are actually longer than the amp itself!

Gorgeous vintage looking brushed gold finish with intact lettering. No rust of signs of use anywhere.

Simple design and easy to service if ever needed. We put it through our thorough testing process, and replaced the illumination bulb.

The SkyFi Testing Process for Amplifiers (Solid State):

We start with a visual inspection of all internal components to make sure there are no signs of stress or aging. Capacitors are checked for telltale sings of bulging or leaking, resistors are checked for signs of overheating or cracking, and transistors are checked for signs of stress or damage.

We then power up the unit carefully and run a simple 1k sine wave while monitoring the output on an oscilloscope for signs of distortion or noise. Finally, we run the amplifier to its full rated power into the appropriate resistive load provided by our Sencore amplifier tester. If there is an issue, it will usually be noticeable at this point. If everything reads clean, we will often test for THD (Total Harmonic Distortion) measured by our Keithley distortion meter, and compare it against the original manufacturers specifications. The amplifier then remains powered on to "burn in" on our test bench for a few hours to make sure there are no heat related issues. If there are balanced inputs available they will be also be tested.

Final testing involves pushing actual music thorough the amplifier. We've learned over time that some issues are only noticeable to a trained ear while listening to familiar source material. Our test bench has reference vintage KEF speakers that we're very familiar with which quickly reveal any discrepancies. Some amplifiers will then move into our listening room where they are tested with our in-house reference speakers of choice.

Please click here for detailed specifics regarding our specialized packing process that separates us from the rest.



Original Box







Yes - Power

Physical Condition


Working Condition