Number of output channels supported by the receiver, determines the maximum number of speakers that can be connected to it. The first digit refers to surround channels to which we connect standing or hanging loudspeakers eg. front speakers, center speaker or surround speakers. The second digit is the number of possible subwoofer connections.

For example to the 5.1 receiver we can connect 5 surround speakers ( the most popular set is 2 front speakers, center speaker and two rear speakers) and 1 subwofer. Standard 5.2 allows you to connect another subwoofer. Settings 7.1 and 7.2 allow 2 additional surround speakers.

In receivers supporting Dolby Atmos there is a third digit, indicating number of speakers placed over head. For example, in standard 9.2.2 we can connect up to 9 spatial loudspeakers, 2 subwoofers and 2 hanging speakers.

 Source: information service RMS.pl

HDMI Standard defines the ability to benefit from features offered by devices such as: 3D image, audio return channel, Ethernet function in the device.

HDMI 1.1 (May 2003)
This is enhanced version of HDMI 1.0. The only change, compared to the original version, is addition of support for DVD-Audio discs.

HDMI 1.2 / 1.2a (August 2005)
The main changes, compared to the previous version, in this standard is addition support for Super Audio CD.

HDMI 1.3a (November 2006)
HDMI 1.3a is an addition of support for new music standards such as DTS-HD Master Audio and Dolby True HD. This lossless form of audio coding is used in Blu-ray and HD DVD devices.

HDMI 1.3b (October 2007)
Brings a very important thing, significant increase of maximum resolution of 2560x1600p, and twice the color depth, which now is 48bit'ów.

HDMI 1.4 (May 2009)
Addition of Ethernet channel and audio return channel, resolution 4K

HDMI 2.0 (announcement at the end of 2013 or beginning of 2014) - The obvious direction of change is better standard adjustment of Ultra HD, that is increase of the maximum TMDS bandwidth. There supposed to be added new 3D features and more audio channels. For the exact specification we will have to wait a little longer, as well as to adapt the hardware manufacturers to new technologies.

Source: information service RMS.PL

ARC - Audio Return Channel, a standard that will reduce the number of cables needed to download audio device. Particularly useful functionality in situations when the TV gets audio and video signal directly from a TV antenna. This way, the new Audio Return Channel allows to send the audio stream to the receiver based on the HDMI connection without the need for additional cable connections.

Source: information service RMS.PL

HDCP (High-bandwith Digital Content Protection) is a form of digital materials copy protection initiated by Intel Corporation. Protocol protects copyrights, prevents from transfer of illegally copied materials. HDCP specification is reserved by law. Its use in device requires the purchase of a licence and producer agreement for certain conditions, eg. prohibition of making copies by the device.

Source: RMS.pl information service

Maximum quantity of radio frequencies in device memory.

Source: RMS.pl information service

Signal to noise ratio (SNR) expressed in dB is the difference between useful sound signal and autio track noise. The higher this ratio, the better, cleaner, less hissing sound.

Source: RMS.pl information service

Signal to noise ratio (SNR) expressed in dB is the difference between useful sound signal and autio track noise. The higher this ratio, the better, cleaner, less hissing sound.

Source: information service RMS.pl

Signal to noise ratio (SNR) expressed in dB is the difference between useful sound signal and autio track noise. The higher this ratio, the better, cleaner, less hissing sound.

Source: information service RMS.pl

Some of home cinema AV receivers and subwoofers are equipped with auto calibration microphones. Microphone is being located in different places in the listening room. Then it automatically adjust sound characteristics, like tonal balance, volume level, crossover.

Of course, auto calibration is optional feature. Each AV receiver and subwoofer can be adjusted manually. For novices, we recommend to use auto adjust systems, and only after that possible individual regulation.

Source: RMS.pl informational service

Picture-in-picture (PIP) feature allows to simultaneos displaying two or more programmes (channels). Main program is displayed on the full TV screen, remainings are displayed in the same time in other windows. Soundtrack is usually played from main program.

Source: RMS.pl informational service

HDMI pass-through allows to transmit HDMI signal from HDMI IN to HDMI OUT without processing it. This function may be used e.g. when the processor is in standby mode.

Source: RMS.pl information service

Wi-Fi is a technology designed to build local area wireless networks. It allows an electronic device to participate in computer networking in 2.4 GHz USF and 5 GHz SHF ISM radio bands. The standard characterizes relatively long range (up to 120 feet).

Device audio with Wi-Fi can play music sent from Wi-Fi transmitters, like smartphones, tablets or PCs and MACs. Wi-Fi is able to convey audio signal using a losless codec. There is absolutely no loss of audio fidelity. Some devices (e.g. VOCO) may link with musical services, like YouTube.com or Spotify via Wi-Fi.

Source: RMS.pl information service

Universal Plug and Play (UPnP) is P2P type protocol that enable networked hardware devices and software applications to communicate and work together without end user configuration. It's an open architecture. Computer which supports UPnP automatically configures its network interface card and shares informations about its gateway. Thereby compatible devices and network applications may be instantly turned on without additional configuration (except for networks with password).

In AV solutions a main goal of UPnP is interoperability between controllers and devices, e.g. enabling audio files to transmit from a NAS to an AV device without necessity for using control device.

Source: RMS.pl information service

Apple's own wireless platform, enabling users to transmit digital audio or video content from iPods, iPhons, iPads etc. to other AirPlay supported devices (wireless speakes, AV receivers).

Compared to Bluetooth, AirPlay has the capability of playing acorss a much larger distances between devices. Therefore, AirPlay uses lossless audio compression.

Source: RMS.pl information service

Wireless platform that can be found in extremely wide palette of devices. In audio, it allows to connect between devices and stream music straight from phone to speakers, AV receivers etc.

Compared to AirPlay, Bluetooth-connected devices need to be close proximity (10-15m). Furthermore, it streams in lossy compression, but is also capable of sounding very good, especially with AAC and aptX codecs.

Source: RMS.pl information service

Control app avalaiblity on smartphones and tablets with Androd, iOS (Apple devices: iPhone, iPad, iPod etc.) or other (e.g. Windows Phone).

Source: RMS.pl information service

Avalaiblity to play digital internet radio, transmitting streaming auditions.

Source: RMS.pl information service

Services, applications and streamers support. Thanks to that feature, you can play music e.g. from Spotify with AV receiver or streaming player.

Source: RMS.pl information service

Apple devices support via device USB port.

Source: RMS.pl information service

Devices and file systems supported by USB port.

Source: RMS.pl information service

Designation of different speaker outputs. Depending on connection, different speaker systems realize various functions: center channel speaker, front speakers, surround speakers etc.

Source: RMS.pl information service

Number of optical inputs - TOSLINK interfaces which are sending digital audio signal (S/PDIF) by optical fiber cable.

Source: RMSStore.eu information service

Number of coaxial inputs.

Coaxial (concentric) cables send digital signal audio (S/PDIF). They are characterized by good electrical properties with RCA connectors and 75 Ohm impedance.

Source: RMS.pl information service

Number of line 2xRCA inputs, popularly named cinches. It's one of the most popular connectors standard used in AV devices. They are sending analog signal.

Source: RMS.pl information service

Number of line 2xRCA inputs, popularly named cinches. It's one of the most popular connectors standard used in AV devices. They are sending analog signal.

Source: RMS.pl information service

Type of headphone output in device.

Important - if your headphones using different type od connector, you still can use them with device, thanks to suitable adapter.

Source: RMS.pl information service

Ethernet input allows to connect to device LAN cable from router, computer or server. It significantly raises device capabilities, enlarging it by playing files through DLNA, supporting network apps or softwarte actualizations.

Source: RMS.pl information service

Additional zones are independent audio/video outputs, which allow to connect speakers or displays (in case of HDMI & video outputs) in the second (third, forth... it depends on amount of zones) room. Thanks to that feature, you can send different signals to these rooms. For example, while one person watches a movie in the living room, the second can listen the music from CD player in the kitchen.

Source: RMS.pl information service

Number of HDMI outputs.

HDMI (High Definition Multimedia Interface) was created in 2003. It is used to transmit uncompressed audio and video signal. You can find HDMI inputs in such devices, as DVD/Blu-ray players, AV receivers, projectors, TVs and more.

Source: RMS.pl information service

Quantity of HDMI outputs.

HDMI (High Definition Multimedia Interface) was created in 2003. It is used to transmit uncompressed audio and video signal. You can find HDMI inputs in such devices, as DVD/Blu-ray players, AV receivers, projectors, TVs and more.

Source: RMS.pl information service

Number of component outputs.

Component interface transmits analog video signal. This signal has been split into two or component channels: two color signals and the luminance. Thanks to it, distortions are reduced to minimum. Component video socket allows for transmition HDTV signal and DVD support. Maximum resolution is 1920x1080p. The most popular connectors are 3xRCA.

Source: RMS.pl information service

Trigger is used to remote start-up connected devices by sending current signal (typically 12V) from main device. Then, after turning it on (eg. AV receiver) other devices (eg. Blu-ray player, phono preamp, etc.) start-up automatically.

Source: RMS.pl information service

The other types of connectors, described in the above specifications.

Source: RMS.pl information service

Subwoofers in the vast majority are active constructions, having their own amplifier. For this reason, subwoofer outputs in audio-video devices are derived from the preamplifier. Subwoofer uses then own amplifier and it can use receiver adjustments and sound correction.

Source: RMS.pl information service

Stereo sound transmission algorithm, using mainly in wireless Bluetooth technology. Depending on the codec version, it allows to transmit files with higher bitrate and frequency response.

Source: RMS.pl information service