If looking for a slimline model other than those available via Marantz then you are going to be very limited as far as choice is concerned. You'll not get many options if wanting one than is less than 5" in height. 5" equates to 127mm. The Yamaha RX-S602 is 111mm high, but you'd not then be left with much space above the AV receiver for ventilation. It is ordinarilly recommended that you leave at least 25mm min above an AV receiver in order to allow heat to diserpate. While the Yama AVR would fit into the space you have available, the ventilation space above it wouldn't be ideal.
Compact, high-quality 5.1-channel network AV receiver with enhanced functionality and advanced features.
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The Yamaha AV receiver uses conventional binding posts as speaker terminals:
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These are far better than spring clip connectors. Either spring clip or binding posts will facilitate bare wire speaker wire connections, although you can also utilise 4mm banana plugs if required with the Yamaha.