The receiver for the speaker system is the heart of the home theater. All cables, connections and other components work through it. The device manages audio and video signals from all sources and powers at least five speakers. The question of how to choose a receiver for the speaker system may seem extremely difficult, but if the answer is correct, then the reward will be huge. A well-chosen AV receiver is pleasant to use, and it will allow you to use speakers and other components as efficiently as possible.
What is a receiver for speakers? It simultaneously functions as a multi-channel amplifier and surround processor. For the most demanding speakers and rooms, it may be better to purchase these components separately. But for most home theaters, an AV receiver would be perfect.
Modern systems make extensive use of the HDMI 1.4 standard, which includes the HDMI Ethernet function, which allows devices to exchange data with each other and Internet connections, a reverse audio channel that allows you to transfer audio back to the AV receiver, and a micro-connector. Other features include support for 4K and 3D resolution .
Energy Efficient Amplifier Topology
A typical AV receiver uses class AB amplification, which works well, but consumes a lot of energy. More effective alternatives are emerging. One of the most promising is class D. An analog signal is converted into a sequence of pulses and is used to turn devices on and off, not allowing them to work continuously. Class G and H amplifiers and receivers are not new, but they are gaining popularity. They use various circuits with relay switching and tracking, which supply voltage to the output devices no more than what is needed at a given time. Manufacturers are finding ways to make these energy-efficient solutions sound better, and they are expected to eventually capture most of the market.
5.1 speaker system
The receiver creates 5.1-channel sound as follows: three speakers in the front, two in the rear on the sides, and a separate one for low-frequency effects. However, with the exception of entry-level models, most of them have seven gain channels. This includes basic 5.1 and two more for volume expansion modes. The latter include frontal height, frontal width and rear. Although Yamaha has been making frontal high-altitude presence channels for some time, today you can find AV receivers that receive Dolby Pro Logic II or Audyssey DSX high-altitude signals. However, for latitude channels, the only option is DSX. Ironically, only the rear ones are supported by the DTS-ES or Dolby EX codecs. DPLII and DSX are the only processing modes that reproduce height or width channels.
Are they needed? Altitude adds a new dimension to some films, but not music. Conversely, width changes little in films and even less in music. The rear surroundings can be useful if the surround side speakers are not enough to cover a long narrow room. However, additional channels may not justify the cost and hassle of installing speakers in the room.
Low volume, equalization and compression
The founding fathers of modern soundtrack for films decided that each AV receiver, speaker system should be calibrated at a basic level of 85 dB. But most people at home set a lower volume. As practice shows, when decibels fall below the reference level, human hearing naturally changes. As a result, dialogs become harder to catch, background sounds disappear and the sound field collapses. In addition, it is likely that the sources connected to the rear panel of the receiver give different input volumes, which requires constant annoying manual adjustments.
Technologies have come to grips with these problems. THX Loudness Plus (part of Select2 Plus and THX Ultra2 Plus), Dolby Volume and Audyssey Dynamic EQ strive to maintain consistent tonal balance, impact and surround at a lower volume. Dolby Volume and Audyssey Dynamic Volume also have the ability to equalize different signal levels from different sources or TV shows and commercials. Both technologies are capable of performing advanced dynamic range compression within a specific program. This is similar to the more sophisticated version of the night listening mode of receivers of past years (unfortunately, they are often incompatible with modern surround codecs). Audyssey Dynamic EQ and Dynamic Volume systems are based on Audyssey MultEQ / 2EQ automatic room adjustment and correction technology. When you turn on the dynamic volume, the dynamic equalizer is always activated. However, it is not tied to the overall volume set by Dynamic Volume. All of these technologies greatly enhance quiet listening. It is desirable to have at least one such system.
Automatic adjustment and correction of the room are two convenient functions for beginners, which, as a rule, accompany each other. They can be either licensed or branded.
Auto tuning
If the thought of setting up the receiver-acoustic kit fills you with fear, then this can be left to the automation. Such devices are equipped with a small microphone. After placing the receiver in place of the listener and activating the automatic installation program, it will emit test signals and configure itself. The equipment will determine the size of the speakers, the distance to them and other parameters. This function is intended for beginners.
Room Correction
Acoustic receiver also allows you to make room corrections in order to fix bass and other sound imperfections. But keep in mind that these equalizers do not always provide the best sound. But you can always turn off the equalizer if the correction result is not pleasant. Some models allow manual fine-tuning.
Many manufacturers use their own settings and room correction systems, but Audyssey versions are most often licensed and considered one of the best. Audyssey MultEQ measures the response of speakers located in eight positions and combines it with an equalizer in such a way as to optimize sound in a wide listening area. 2EQ does the same for the three positions. For a quiet sound, Aaudyssey Dynamic EQ uses Multeq or 2EQ as the basis, adjusting the frequency response and the balance of the environment when increasing and decreasing the signal. Correction of the room, of course, may be useful, but it will not replace the correct placement of speakers and other basic settings. The program is licensed for use by Denon, Integra, Marantz, Onkyo, NAD, etc. Another licensed system for automatic installation and correction of premises is Trinnov, used in Sherwood receivers and surround sound processors by Audio Design Associates.
THX Certification
The THX-certified speaker with acoustics has sufficient power to work with THX-certified speakers for a nominal sound level in rooms of a certain size. These receivers also support cinema mode, which includes, among other things, a scheme for suppressing overly bright soundtracks for Re-EQ movies. THX contributed to the creation of the 7.1-channel version of Dolby Digital, but most features are an overlay for existing surround codecs. The standard is beneficial to use in the context of fully THX-certified systems. In other words, with a certified receiver and speakers you can get all the benefits of compatibility and integration.
Dolby and DTS surround sound decoding
Surround sound in the best case is the result of a discrete encoding-decoding process (the so-called codec). It is included in the software and decoded in hardware at home, without creating false or derivative channels received from others. Dolby and DTS formats are the foundation of home theater technology.
DTS-HD Master Audio, Dolby TrueHD
These standards provide much more efficient data storage than uncompressed PCM. They remodel the master soundtrack bit by bit. In this case, the user receives exactly what the engineer encoded. Blue-ray fans will need these codecs in any of their players or AV receiver. If a home receiver can receive a high-resolution PCM signal via HDMI, then it does not need to have a lossless decoding system. Decoding is not the best solution, because it does not allow you to hear the so-called secondary audio, such as comments or windows with bonus images that can be called up during the main program.
Audio DTS-HD, Dolby Digital Plus
These are the so-called lossy compression formats, because during the encoding-decoding process they omit some data that becomes inaccessible during playback. But this is done more intelligently (and sometimes at higher data rates) than in older Dolby Digital 5.1 and DTS, and as a result, a clear and high-quality sound is obtained.
Dolby EX and DTS-ES Discrete / Matrix
These are improved versions of DTS and DD 5.1 with surround back sound. Dolby EX is a 6.1-channel connection of speakers to the receiver, although here, as a rule, one channel is divided between two systems. It decodes the rear-rear surround sound, which does not allow calling it completely discrete. The DTS-ES acts in a similar way, although in this case the rear rear is truly independent. These codecs are used in some releases on DVD and Blu-ray.
DTS and DD 5.1
These are the basic lossy audio compression codecs used in DTV broadcasting on almost every DVD and some Blu-ray discs. Appearing in the mid-90s, they replaced the analog Dolby Surround. They digitally separately and independently encode each channel using the perceptual method of selectively skipping data that is considered the least significant or masked by other sounds.
Dolby ProLogic IIx and IIz
This is partly a surround sound decoding mode (works on analog Dolby Surround encoded in two-channel soundtracks, surround expansion mode of any 2-channel source. It includes options for music, movies, games and rarely used emulations of the original Dolby ProLogic. DPLII music mode is reliable a way to connect a two-channel source to a 5.1 system while preserving the original stereo effect, but to many it will not replace pure stereo. Its 7.1-channel version (with rear surround) is Dolby ProLogic IIx, which can output from 5.1 7.1. Its 9.1-channel version (with rear and high-altitude signals) is called Dolby ProLogic IIz.
Circle Surround, DTS Neo: 6, Neural Surround are competitors of the DPLII family. They extend stereo to surround sound using a variety of approaches.
Universal DSP Modes
“Hall”, “stadium”, etc., are not of great value to most users and can be misleading if used improperly. These modes rarely add true realism and can significantly reduce the sound quality of the audio system.
Main amplifier: 7.1 or 5.1?
Despite the proliferation of additional surround channels, there is no need to use the acoustics connection to the receiver according to 7.1. You can simply turn off the last two in the control menu and enjoy the additional dynamics of the other five. In some models, it is possible to repurpose the rear channel to strengthen the front left and right speakers or to power the second zone.
Deceptive Specifications
The specifications of the receivers are full of false information. They are misleading when the published figures relate to only one or two channels, which looks better than the general situation. When comparing the characteristics, the phrase “all channels” should be sought. In addition, to determine the characteristics of the system, either the entire frequency range or only 1 kHz can be used. The duration of the test signal also has a large effect on the output power. The most challenging test to date is continuous pitching. Many manufacturers claim that the audio material does not contain continuous tones on all channels at the same time, so they sometimes use signals with a duration of several milliseconds as a more realistic test. Unfortunately, there are many versions of such measurements, often called peak or dynamic power, which makes comparisons pointless. Slight differences in total harmonic distortion (THD) may be inaudible. And although manufacturers love to advertise this feature, most products on the market are doing well in this regard. The best advice would be to get acquainted with the test results, which allow you to determine what real power the receiver-speaker set has.
What power is needed?
In order for the receiver for the speaker system to match the speakers, you should familiarize yourself with their specifications and find out the recommended amplifier power and rated resistance. Speakers with an impedance of 6 ohms or less represent a more complex load than 8 ohms, since they require more current. This means that the AV receiver will heat up more. The number of watts for a speaker with a resistance of 4 ohms is almost always higher than that of an 8-ohm one, however, the actual rated load of the speakers may not correspond to 4 ohms, regardless of what specifications they are sold with. It must be remembered that the resistance changes with frequency and the nominal value indicated on the dynamics is largely silent. Amplifiers and receivers should provide the desired volume without distorting the sound or overloading. It is necessary to take into account the size of the room, the distance to the speaker system and the sensitivity of the speakers. This is where THX certification, speaker manufacturer recommendations, and a trusted seller can be of great help. If 5 or more powerful speakers are used, you may need a better signal source than the one in the receiver. You probably need a good multi-channel amplifier.
Cross Convert to HDMI
Many new receivers today allow you to convert all the input signals for HDMI output to connect only one cable to the display. This, of course, is a desirable convenience, but its performance may be dubious. Some devices do this better than others, and it is often written in small print in the operating instructions for THX-certified AV receivers that such a conversion is not recommended.
HDMI Connector: Key Interface
HDMI is the most versatile interface in modern home theater systems. If AVR and signal sources support it, then this can greatly simplify their connection.
When this standard first appeared, there were problems with component compatibility. But with their coherence, new HDMI receivers win for two reasons. First, HDMI is a carrier of both audio and video, which reduces the overall cable clutter. Secondly, many receivers direct all incoming signals to one output for a simple single-cable connection to the display. HDMI 1.4 includes support for 3D, Ethernet, an audio return channel, and a micro-jack.
Acoustic receiver with HDMI 1.3 (or higher) is capable of processing multi-channel PCM high resolution and allows you to decode codecs without loss. This standard is required for work with Blu-ray-players. HDMI 1.3 supports surround codecs like native streams. Older versions of the standard are capable of transmitting some of them, but only 1.3 and higher make it possible to work with most, including DTS-HD Master Audio and Dolby TrueHD.
PCM via HDMI
Why is it important that the receiver for the speaker can handle multi-channel, high-resolution PCM data through the HDMI ports? Firstly, because many Blu-ray discs offer multi-channel PCM soundtracks. Secondly, because many movies on Blu-ray players can convert Dolby TrueHD and DTS-HD Master Audio to uncompressed audio format for HDMI output. Lossless audio can be obtained even if the AVR does not provide decoding of new codecs. In addition, it allows the player to add additional audio tracks.
Deprecated Ports
Component video, like HDMI, is a form of HDTV connection. Transmits only high quality analog video.If the AV receiver has only one HDMI output, this connection will allow you to connect a second monitor or solve compatibility problems. It is a red, green and blue connectors that are on older televisions and DVD players.
S-Video is an analog video connector in which the brightness and color signals are separated to avoid cross-color distortion. It mattered before the advent of HD, but today is not necessary. S-video does not support high definition and in modern receivers starts to fade.
Composite video uses a yellow connector, and it also does not support high definition. Composite and S-video are used in Laserdisc players, video recorders, analog cable TV set-top boxes and other antediluvian signal sources. It is best to get rid of such equipment as quickly as possible.
Digital coaxial and optical connectors
After HDMI, the next best choice is a digital connection using a coaxial or optical cable. There are different opinions about which one is better, but they are approximately equivalent. Coaxial and optical digital outputs are available on DVD and CD-ROM players and in various consoles. However, neither coaxial nor optical digital connections are compatible with future generations of high-resolution audio. However, they are capable of transmitting Dolby Digital and DTS standards.
Analog input and output
Some of the sources with analogue connectors for 7.1 or 5.1 systems include Blu-ray players, SACD, DVD-Audio and very old DVD players. They can bypass the bass control of the receiver and other settings, so you need to use HDMI wherever possible.
The preamp outputs can be useful if you need to upgrade your audio system and use your home receiver as a surround processor, along with a larger power amplifier for all or some channels. This also includes connecting a subwoofer.
Cassette racks and other analog sources may require stereo connectors. The player requires a special input, otherwise you will need to connect an external phono stage.
Multi-zone
Most models of receivers support multi-zone, that is, they are capable of serving more than one room and several input sources. Multi-zone video is usually implemented in the form of composite or S-video standard resolution. Multi-zone audio is typically analog stereo. Multizone focuses more on convenience than high quality. Some devices also have a second remote control.
The Yamaha RX AV receiver, for example, has an intelligent distribution system for gain channels, depending on the features that are currently selected. For example, if the second zone is disabled, all 7.1 channels will be used in the main one. When you turn on the second zone, the power of the two rear will be directed to its two speakers, and the main one will remain with the 5.1 system. This eliminates the need to manually switch cables on the back of the receiver.
Ethernet
The receiver with speakers using an Ethernet cable can connect to the router to access Internet radio, music, photos and video from a PC. Some network connections are certified by the DLNA Home Digital Network Alliance, while others are Windows certified. And they can do without licenses. If the music library is recorded on the hard drive, then such a connection becomes simply necessary. In addition, regular firmware updates are required, and Ethernet connectors allow you to do this online, which is better than other methods. Of course, a Wi-Fi connection can be even more convenient, but for streaming media, it is much less reliable.
Additional interfaces
- Most AV receivers have an iPod dock. You can purchase a universal dock that connects to any analog input. Some receivers provide direct connectivity.
- The Yamaha RX AV Receiver supports AirPlay, which enables you to wirelessly stream music from your iPod, iPhone or iPad, or iTunes from your Mac or PC. This allows you to listen to music from mobile devices or a home theater. You can also view metadata such as the title of the song, artist, and album art.
- USB is useful for connecting hard disk drives or flash memory. Bluetooth receivers for speakers are also available.
- Additional ports include an infrared receiver connector that allows you to control the receiver when it is hidden in a cabinet.
- A 12-volt trigger activates other devices, such as projectors, motorized screens and curtains.
- RS-232 is used to replace software or connect third-party control systems.
Remote control
Another problem is remote control. If you do not plan to purchase a universal remote control, you must have something with buttons, clearly distinguishable in shape and color. Many remotes can be trained or have programmed command libraries. They can control other devices, such as HDTV and disc players. Also, if you watch movies in a darkened room, a remote control capable of turning on the light at the command will become a godsend.
A good receiver will be a source of constant satisfaction for many years.