The Marantz 4300 Quadradial was one step down from the Marantz 4400 Quadradial.  It is a 2 channel or 4 channel receiver with built in Dolby B Noise Reduction. It also has an optional plugin for and SQ decoder. In 4 channel mode it is rated at 40 watts per channel.  In a 2 channel setup it is rated at 100 watts per channel. I believe it was first produced in 1972 and ended production in 1978. It listed at $899.95.

The Marantz 4300 has inputs for Phono, FM, AM, 2 tapes sources, and an external discrete 4-channel source.

The Mode knob can switch between Mono, 2-channel, Discrete, Vari-Matrix, and SQ Decoder modes. When using the Vari-Matrix mode the Dimension knob allows fine tuning of the four channels "surround" effect.

 

 
The Marantz 4300's can sell from around $200 for a parts or poor condition unit up to $600 for a unit in excellent working condition. Apparently the 4300 would also work with the Marantz RC4 remote control.  It also used the WC-43 wood case.