Harman Kardon's AVR645 receiver is a fantastic choice for mid-range users who want a quality device at a reasonable price. With a huge array of connectivity options and a brilliantly designed remote control, there are very few reasons not to purchase this product if it's in your price bracket. An upgraded version of the AVR 635, the 645 brings HDMI and USB connections to the already massive bevy of ports on the receiver. With excellent audio and video performance and an impressive feature set, the AVR645 is a standout product.

The Harman Kardon's rear panel is replete with every input an AV buff needs, including two HDMI, six composite, three component, three optical audio, three coaxial, four S-Video and a USB port. Outputs include HDMI, composite, component, S-Video, optical audio and speaker connections for 7.1 surround sound. The front panel also boasts a headphone jack, as well as coaxial and composite ports, which can be configured as either inputs or outputs, depending on what's needed. In the process of setting up an entire home entertainment system, including home theatre surround sound, DVD player, set-top box and of course a television, the AVR645 provided every single port we could possibly have needed.

The audio section of the receiver is impressive. The large array of high-end audio connections ensures that users can connect many devices without losing audio quality. Support for Dolby Digital, DTS and PCM is included, and with the impressive inbuilt equaliser and high number of preset options, audio output is sharp and clear. Users can even connect an iPod with the optional Harman Kardon The Bridge. After performing the relatively simple calibration process, we found its surround sound performance to be excellent, filling the entire room with a full, rich sound.

Video support is just as impressive, especially considering the AVR645's ability to convert analogue video signals to digital, allowing composite inputs to be outputted via component connections, helping to reduce clutter from excess cables. The HDMI connections are the real winners here, however, delivering digital video and audio in the same cable and making the AVR645 a great choice for AV enthusiasts.

The 645 boasts the same impressive remote control as the AVR 635, and while it's by no means a top-end universal remote, it's relatively simple to program. Combined with the massive array of ports on the unit itself, the AVR645 brings together your entire home entertainment package into a single, compact bundle.

As with the AVR 635, the AVR645 is let down only by its on-screen display. While it's a little easier to read, it can be a little tricky to navigate. Nevertheless, the simplicity of the entire package, and its power to connect itself to almost every electronic device in your living room, makes it a great purchase. The recommended retail price may seem a little high, especially for casual users, but if it's within your price range it's very hard to find a reason not to buy this product.