The Marantz 4400 is a classic quadraphonic 4 channel receiver into which Marantz pretty much threw everything they had. Offered from about 1974 until 1978, it pushed out 125 watts RMS per channel into 8 ohms in 2 channel mode and 50 watts per channel into 4 channels which was pretty powerful for a quad receiver. It did this with under 0.15% total harmonic distortion from 20 Hz to 20 KHz.
Marantz also not only incorporated built in Dolby Noise Reduction into the 4400 but gave it six different controls.
The tuning section of the 4400 utilized Phase Lock Loop FM Multiplex Demodulation which is a complicated way of saying that it could effectively lock onto an FM channel and hold it.
If you bought the Marantz 4400 quadraphonic receiver but really only had 2 channell recordings theyou didn’;t have to worry because the 4400 has what is called Vari-Matrix Synthesis which “synthesizes” 4-channel sound from 2-channel material.
Probably the most iconic aspect of the 4400 and some other Marantz receivers is the built in oscilloscope. The scope, located at the top left corner of the front of the receiver has 3 basic functions. First, it acts as a tuning meter and graphically represents channel separation. Second, you can see the signal source and third you can see the effect of antenna position in order to reduce distortion. The oscilloscope utilized a Hitachi 50TB31 tube for the display.
Marantz added separate balance controls for the front/front and rear/rear speakers as well as a separate control for balance between the front and rear speakers. Marantz offered as an option the WC-43 wood case which really adds to the look of the 4400.
Another interesting feature was the built in interchangeable matrix decoder socket. You could purchase different decoders and plug them into the socket. That way you would be sure that the 4400 would be able to decode your specific qhadraphonic material. At the time they had SQA-1, SQ/QS-1, SQA-2, QS-3 and CD-4 decoders.
Marantz collectors salivate over the 4400 today and prices reflect that demand. A fully restored 4400 can easily sell for over $2500.00