Comparison Denon AVR-S660H vs Denon AVC-S660H

— AM/FM radio. The presence of a built-in tuner that allows you to receive AM and FM radio broadcasts without additional devices (except perhaps an antenna is required, and then not always). In FM, it is possible to realize the transmission of high-quality stereo sound, however, the waves propagate only within the line of sight (10-20 km); therefore, most of the stations in this range are classified as "urban music". In AM, the transmission range is already measured in hundreds of kilometers, but the sound quality is noticeably lower; therefore, such stations usually specialize in talk programs (particularly news).

— USB stick. The ability to connect a USB drive to the receiver — for example, a "flash drive" or an external hard drive — and play content from it directly. This requires a USB connector. Most often, in models with this function, it is located on the front panel (see below) — this provides ease of connection; at the same time, there are exceptions. Also note that the very presence of USB does not necessarily imply the possibility of playing from external media — this interface can be used for service purposes, for example, to update the firmware or play from a PC (see "Advanced (inputs) — USB Type B").

— Network audio streaming. The ability to play streaming audio over a local network or the Internet (including from services like Groo...veshark or Last.Fm). The name "streaming" is due to the fact that each song is played directly from the network, without being written to the receiver's own permanent storage. This function, by definition, requires connection to computer networks; most often, a Wi-Fi module is used for this purpose (see "Interfaces") or a LAN connector.

— Internet radio. The ability to use the receiver to receive and play Internet radio broadcasts. This feature is similar in many ways to the network audio described above — in particular, it requires a network connection to work, and the data is streamed; however, in the case of network audio, the user himself chooses what and when to listen, here the broadcast is similar to conventional radio transmissions and is controlled from the radio station. Actually, many major stations broadcast their programs not only on the traditional air, but also via the Internet; There are also specialized projects broadcasting only on the Web. In general, the choice of programs is much more extensive than for conventional radio broadcasting — after all, Internet radio has no range restrictions. And the receivers themselves may provide additional tools for managing such broadcasting — for example, catalogs, search by genres, languages, etc.