AV receivers are typically big black boxes, so I welcome units that stand a little shorter. They can squeeze into tighter shelves and, if nothing else, look a little sleeker on your AV rack. 

Marantz leads the way In compact, full-function receivers, but other brands have also proffered half-size units in the last year or two. The slim-line RX-S601 was one of Yamaha's first official MusicCast components back in 2015 and so a follow-up has been a long time coming. 

Read: Best AV receivers under $500  

The new Yamaha RX-S602 will be available in August for $649 or £599. Australian pricing is yet to be confirmed but expect it to be the same as the RX-S601 at AU$899.

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The Yamaha's smaller size does mean some compromises. It's rated at a fairly low 55 watts per each of its five channels (plus subwoofer out), and also offers fewer inputs. But if you want the missing link between a sound bar and an AV receiver, slimline units come as close as anything.

From the outside the 602 looks identical to the 601, and it's also the same price at $649.95. The biggest change is a reduction in HDMI ports from six to four, but at least those four are now compatible with 4K sources, including HDR and Dolby Vision.

The RX-S602 works with MusicCast Surround, new in 2018, which lets you connect a wireless set of rears. It can also accept a limited selection of Alexa voice commands for users of an Amazon Echo or similar Alexa speaker.

The Yamaha wireless connections include Wi-Fi (Apple AirPlay and Spotify Connect) and Bluetooth. The onboard MusicCast supports numerous streaming services, including Pandora, SiriusXM, Tidal, Deezer and Napster. Yamaha is not an official partner for AirPlay 2 and has made no announcements about compatibility yet.

The receiver also includes Zone 2 audio, but since it uses the rears of the 5.1 channels, you're limited to a 3.1-channel setup in one room and a two-channel configuration in a second room.

At this price choosing the slim-line $550 Marantz NR1509 or $750 NR1609 looks like a better deal due to those models having more HDMI ports, along with more channels and Dolby Atmos capability.