Friday, May 17, 2013





 Marantz Model 500 Monster Power Amplifier

The Marantz 500 was a monster amplifier of the early seventies and one of the last equipment designed and built by the early group in Sun Valley, CA, USA. The panel was brushed, gold anodized and black enamel. The meters were blue.
Its specifications were quite exceptional, with over than 250 Watts RMS per channel into 8 ohm loads, 20 Hz to 20 kHz. The total harmonic distortion was under 0.05 %, the power bandwidth 5Hz to 45 kHz at 0.1 % THD, the damping factor greater than 400, the hum and noise better than 106 dB below 250 W.
The power supply included a 2.2 kW transformer and computer grade electrolytic capacitors capable of storing energy in excess of 280 joules. A delay circuit for limiting to 50 A the AC in rush current was operated at power-on.

The baby is for sell on ebay "AS IS" for $1500. I seen one of these sell for $4200. The unit was picked up from a electronic repair shop that went out of business. The problem with the right channel is very low sound output. The left channel has 3 or 4 bad output transistor. The left channel was dis assembled, but has since been re assembled. A nice amplifier to restore. 

Check out my Classic Audio Pieces http://oahuenterprises.com/