Comparison Marshall Acton Multi-Room vs Harman Kardon Aura

The total sound power provided by the audio system at maximum volume, in other words, the total power of all the speakers provided by the device (including the subwoofer).

The higher the power, the louder the system will sound and the larger the area it can cover. On the other hand, high power significantly affects the price, dimensions, weight and power consumption of the device. In addition, when evaluating and comparing according to this indicator, it is worth considering some nuances. Firstly, some manufacturers go to the trick and give in the characteristics not the average, but the peak sound power; such numbers can be quite impressive, but they have very little to do with real loudness. So if it seems to you that the claimed power is too high, it's ok to clarify what exactly is meant in this case. Secondly, when comparing, it is worth considering the presence of a subwoofer — it plays an auxiliary role, but it can account for more than half of the total system power. Because of this, for equal total power, a device with a subwoofer may be quieter than a model without a subwoofer: for example, a 2.0 40W system will have 20W per main channel, while a 2.1 40W model may have 20W per subwoofer, and only 10 watts for the main speakers.

Nominal sound power (see "System power") on each of the main channels of the audio system. This indicator is most often indicated in models with a subwoofer (see "Number of channels"); knowing it, you can estimate the power distribution between the main speakers and the subwoofer.

The number of distinct frequency ranges (bands) into which sound is divided when played through the acoustics of an audio system. For each such band, a separate speaker is provided, and sometimes several.

The simplest option provides 1 lane; it is very popular in modern audio systems, because. requires a minimum number of speakers, and the sound quality can be quite good. More advanced options provide 2-3 bands (low and high frequencies, or bass, treble and medium), and in high-end models, the number of bands can be up to five. Note that, in addition to integers, models are also produced with a fractional number of stripes — for example, 2.5 or 3.5. This marking indicates the presence in the design of a speaker responsible for two bands at once: for example, model 2.5 has separate speakers for bass and treble plus a combined bass + midrange (similar in design to bass, but also loaded with mid frequencies).

Anyway, the abundance of bands, usually, indicates a high class of acoustics: the more separate frequency ranges, the narrower the specialization of each speaker, the more accurately it is able to reproduce its part of the signal, and the more complex the system is.

The total frequency range reproduced by the acoustics of an audio system. Measured from the lower threshold of the lowest frequency speaker to the upper threshold of the highest frequency: for example, in a 2.1 system with main speakers at 100 – 22000 Hz and a subwoofer at 20 – 150 Hz, the total value will be 20 – 22000 Hz.

In general, the wider the frequency range, the fuller the reproduced sound will be, the less low and high frequencies will be lost due to insufficient acoustic capabilities. On the other hand, do not forget that the actual sound quality also depends on a number of other parameters — primarily the frequency response. In addition, human audible frequencies range from 16 Hz to 22 kHz; deviations from these values are very small, and the upper limit also decreases with age. Therefore, from a practical point of view, it does not make sense to provide too large a frequency range; and impressive performances like 10 – 50000 Hz, found in top-class models, are usually more of a kind of "side effect" of high-quality speakers (and at the same time — a marketing ploy) than a really significant moment.

The presence of an equalizer function in the audio system.

Equalizer allows you to change the timbre of the sound by adjusting the volume for individual frequency bands. The simplest version of this adjustment provides 2 bands (high and low frequencies), but most often there are more bands. Anyway, the equalizer can be useful both for fine-tuning the sound to your own preferences, and for compensating for the shortcomings of external or standard acoustics, connected headphones, etc. - for example, if the speakers "fail" certain frequency bands. In addition, many audio systems have a set of equalizer presets (presets), usually designed for different styles of music - "Classic", "Rock", "Pop", etc. You may also be able to create and edit your own presets.

- AirPlay. AirPlay technology was developed by Apple. It is based on Wi-Fi and is used to wirelessly broadcast content from Apple devices to external audio systems. Thus, this function is useful for tech who want to connect an iPhone or iPod touch to the audio system, but do not want to bother with wires; However, it is possible to connect other devices via AirPlay - for example, a PC with iTunes and a Wi-Fi module installed.

- AirPlay 2. The second generation of the AirPlay technology described above, introduced in 2018. Among the main innovations of this version is support for the multiroom format, that is, the simultaneous broadcast of several audio signals to different compatible devices installed in different places. In this way, you can, for example, turn on a radio broadcast of a news program in the living room, relaxing music in the bedroom, etc. In addition, AirPlay 2 received a number of other improvements - improved buffering, the ability to stream to stereo speakers, as well as support for voice control via Siri.

- Chromecast. Original name: Google Cast. Technology for broadcasting content to external devices, developed by Google. Allows you to transmit an audio signal from a PC or mobile device to the audio system; the broadcast is usually carried out via Wi-Fi, while the receiver and the signal source must be on the same Wi-Fi network (with t...he exception of Chromecast media players). Note that in signal sources (smartphones, tablets, PCs, etc.) Chromecast is implemented at the level of individual applications. For example, at the time of its creation, this feature was available, in particular, in the YouTube and Netflix applications for Android and iOS, as well as in the web versions of these applications for Chrome. Thanks to this format, this technology is extremely widespread these days, and the ability to connect a particular gadget to an audio system with Chromecast is usually limited to the ability to install appropriate applications on this gadget.

- DLNA. DLNA (Digital Living Network Alliance) is a standard that allows you to combine various types of home electronics and household appliances into a single network for content exchange and control. In the case of audio systems, DLNA can be used, for example, to play music from the disk of a computer connected to such a network, broadcast sound to a device installed in another room (for example, an amplifier), etc. Connecting to DLNA can be done either wired or wirelessly (using the Wi-Fi standard), and device compatibility does not depend on their manufacturers - the only condition is compliance with the DLNA standard.

- LAN. Standard interface for wired communication to local computer networks based on the RJ-45 connector. Its presence allows you to use various network functions, such as Internet radio (see "Advanced") or DLNA (see above). Compared to another network interface - Wi-Fi - LAN is less convenient due to the presence of wires, but is more reliable and provides a higher actual data transfer speed.

- Wi-Fi. The presence of a Wi-Fi wireless communication module in the audio system design. This technology is used both in computer networks and for directly connecting various devices to each other; its “range” is sufficient to work within residential premises, even through walls. In this case, Wi-Fi can be used to work with network functions such as Internet radio or DLNA(see above). Moreover, this option is more convenient than a wired LAN due to the absence of actual wires. In addition, support for this technology is a prerequisite for using the AirPlay and Chromecast functions (see above); and in some devices, Wi-Fi even allows you to connect smartphones, tablets and other gadgets as remote controls.

One of the most modern and fastest standards of this wireless communication technology is Wi-Fi 5. The 802.11ac version uses the 5 GHz band (less congested and more noise-resistant than 2.4 GHz), providing speeds of up to 1.69 Gbps per antenna and up to 6.77 Gbps with multiple antennas.

— Bluetooth. Direct wireless communication technology between various devices. One of the most popular ways to use Bluetooth in audio systems is to work with an audio signal, primarily broadcasting sound to wireless headphones or speakers; and some models also provide the ability to connect a smartphone, tablet or other device and use the audio system as an external Bluetooth speaker. However, it is worth considering that initially Bluetooth is noticeably inferior to a wired communication in terms of sound quality; however, in our time, this disadvantage is often compensated by the use of one or another version of the aptX codec(see below).
In addition, other options for using Bluetooth may be provided - for example, exchanging files between the built-in memory and the same smartphone, or remote control via an application. They are not mandatory for modern audio systems, but with the development of technology they are becoming increasingly widespread.

In modern audio systems, the Bluetooth v 5 standard is most often used. Its important innovation is the expansion of the capabilities of the BLE (Bluetooth Low Energy) mode: if necessary, the device can increase the range by reducing the speed, or speed up transmission at the cost of reducing the range. In addition, a number of improvements have been introduced regarding simultaneous work with multiple connected devices.

- aptX support. The audio system supports aptX, a codec designed to improve the quality of sound transmitted via Bluetooth. Accordingly, this function automatically means the presence of a built-in Bluetooth module (see above). The need to use special technologies is due to the fact that in the original Bluetooth format the audio signal is very highly compressed, which significantly affects the final sound quality. The aptX technology is designed to correct the situation: according to the creators, it provides sound purity “comparable to Audio CD (16-bit/44.1kHz)” and almost as good as a wired communication. This is often enough even for comfortable listening to lossless formats, not to mention MP3 and other popular compressed formats. Of course, to use aptX, the signal source must also support it.

- aptX HD support. Audio system support for the aptX HD codec - an improved and updated version of the aptX described above. This version claims sound purity comparable to Hi-Res audio materials (24-bit/48kHz); this allows you to comfortably listen not only to MP3, but also to lossless formats and even uncompressed audio materials. On the other hand, aptX HD support is quite expensive, and its advantages over the original aptX only become noticeable on very high-quality audio materials, for which consumer audio systems are rarely used. Therefore, this function is not particularly widespread.

- A.A.C. A codec used primarily in Apple portable devices to improve sound transmitted via Bluetooth. In this sense, it is similar to aptX (see the corresponding paragraphs), but is noticeably inferior to it in terms of capabilities: if the sound of aptX is compared with Audio CD, then AAC is at the level of an average quality MP3 file. However, for listening to the same MP3s, this is quite enough; the difference becomes noticeable only on more advanced formats.

-LDAC. Sony's proprietary Bluetooth codec. It surpasses even aptX HD in terms of bandwidth and potential sound quality, providing performance at the Hi-Res level of 24-bit/96kHz audio; there is even an opinion that this is the maximum quality that it makes sense to provide in wireless headphones - further improvement will simply be imperceptible to the human ear.

— Network streaming audio. The ability of the audio system to work with network streaming audio services such as Deezer, Spotify, Tidal, etc. Such services are designed to broadcast content (in this case, mainly music) over the Internet; in this case, the played files are not saved in the audio system, but are played directly from the corresponding resource on the World Wide Web. Nowadays, there are many streaming services that differ in the range of music and access conditions; The specific list of supported services should be clarified separately. However, in any case, the main advantages of online streaming include an extensive selection of content and almost instant access to the desired composition; Some services can also work like a radio, automatically selecting music according to the producer's preferences.

- Speakerphone. Possibility of using the device as a hands-free system for a mobile phone. In this mode, the audio system connects to the device, most often using Bluetooth (see above), and the voice of the subscriber on the other end of the line is output not to the phone, but to the speakers of the audio system. This is often more convenient than holding the phone to your ear; In addition, speakerphone is useful if several people need to participate in a conversation.

— NFC chip. NFC is a short-range wireless technology (about 10 cm). In audio systems, NFC is used primarily to facilitate communication via Wi-Fi or Bluetooth (see above). With this chip, you can simply bring an external NFC-compatible device to the audio system and confirm the communication - it's easier than manually adjusting settings.

— Omnidirectional sound. As the name suggests, audio systems with this feature emit sound evenly in all directions, covering a 360° space. Thus, the device can be installed in the center of the room and evenly “fill” it with sound, which will be clearly perceived at any point. On the other hand, an omnidirectional system usually sounds in 1.0 format (mono); the design may include various tricks to ensure surround sound, but such systems still fall short of full-fledged stereo in most cases.

— Voice assistant. Support of the audio system of the voice assistant. The most popular assistants nowadays are:

• Google Assistant
• Apple Siri
• Amazon Alexa

However, other solutions can also be used. In any case, it is worth noting that we are not talking about the function of the audio system itself, but about compatibility with smartphones, tablets and other gadgets that have their own voice assistants. Thus, to use the voice assistant, you will have to connect the audio system to an external device. On the other hand, the capabilities of such assistants are usually more extensive than those of built-in voice control systems (see below); advanced functions are often supported, such as natural speech recognition with complex queries (“Play the latest album of the band ... that I listened to”), voicing the weather forecast, sports results, etc. Of course, the specific set of supported commands and languages may vary - depending on the voice assistant and its version.

— Voice control. A function that is practically mandatory for smart speakers (see “Purpose”) and is almost never found in other types of audio systems. As the name suggests, this control allows you to control the device using voice commands. It differs from the voice assistant (see the corresponding section) in that in this case we are talking about the simplest commands related to the main functionality of the audio system - for example, “Stop”, “Continue”, “Next track”, etc. It is worth keeping in mind that voice control almost certainly supports English, but the ability to recognize other languages should be clarified separately.

— Mobile application. The ability to control the audio system from a smartphone, tablet or other gadget with a special application installed on it. As a rule, the connection is via Wi-Fi (see "Interfaces"). The convenience of this function is not only that the system can be controlled remotely - the application is often more convenient and provides more options than the controls on the radio itself.

— Multiroom support. The device supports Multiroom technology. This technology allows you to create a single wireless network in your home from several speakers placed in different rooms, and simultaneously play music in all of these rooms. The specific features of such networks may be different in different models, they should be clarified separately. So, some devices use a Bluetooth connection, others - via Wi-Fi (directly or via a local network). In some cases, the control speaker broadcasts sound to all the others, and the same music plays throughout the house, in others, the speakers are "equal", and different tracks can be played simultaneously in different rooms. Some audio systems require an external sound source (smartphone, tablet, etc.), others are capable of playing the role of a player themselves, including for streaming Internet services.

— Karaoke.... A popular entertainment that allows users to sing their favorite songs to a backing track (musical accompaniment with the original vocals cut out) — so that the vocals superimposed on the backing track are reproduced through the acoustics of the audio system. This function requires at least one microphone input.

— Karaoke Mix. An extended version of karaoke (see above), providing various additional options — for example, assessment of performance skills in points, singing competitions, etc. As a rule, it allows you to connect two microphones.

— Internet radio. The ability to listen to Internet radio stations on the audio system. In general, such broadcasting is similar to conventional broadcasting, but it is carried out not via radio, but via the World Wide Web, which provides some additional opportunities. Thus, Internet broadcasting has no restrictions on range and range, allows you to listen to programs from any country and in any language; and the list of broadcasters is extremely extensive, among them there are both traditional radio stations duplicating their broadcasts on the Internet, and specific, purely network projects. The presence of this function assumes support for at least one network interface - Wi-Fi or LAN (see "Interfaces").

— Recording to a USB drive. The ability to operate the audio system in recording mode to an external USB device, such as a flash drive. This allows you to record your favorite radio programs from a regular tuner or Internet station (see above), copy music from optical discs, etc.; specific USB recording capabilities depend on the audio system model.

— Clock. A regular clock is a device for displaying time, most often in the form of numbers on a display. Sometimes it is precisely such a clock that turns out to be the most convenient. In addition, this function is necessary for some other features — primarily an alarm clock (see below).

— Alarm clock. A classic alarm clock that gives a signal at a set time. It can be useful not only for waking up, but also in other cases when it is necessary to warn the user about the onset of a certain time. The peculiarity of this function in audio systems is that the signal can be the switching on of a certain radio station or musical composition.

— RCA. The RCA interface uses coaxial cables with characteristic "tulip" plugs and corresponding connectors. It can be used to transfer different types of data, however, in this case, it means connecting the audio signal from the preamplifier in analogue format, one channel of audio per connector. RCA is widely used in modern audio technology, but its resistance to interference is very limited.

— Mini-Jack(3.5 mm). Standard connector for most modern portable audio equipment. In audio systems, it is mainly used to connect such equipment — primarily pocket media players. It uses analogue signal transmission, while the resistance to interference, like RCA, is not high, and the quality may even be lower due to the fact that both channels of stereo sound are transmitted over the same cable.

— Coaxial S / P-DIF. An electrical version of the S / P-DIF standard, using a coaxial cable with a “tulip” connector for signal transmission. Do not confuse this interface with the analogue RCA described above — despite the identity of the connectors, these standards are fundamentally different: "coaxial" works in digital format and even multi-channel audio can be transmitted over a single cable. Compared to optical S/P-DIF, this interface is less resistant to interference, but more reliable because electrical cables are not as delicate.

— Optical. One of the va...rieties of the S / P-DIF standard is, along with the coaxial one described above. In this case, the signal is transmitted via a TOSLINK fibre optic cable. The main advantage of this interface is its complete insensitivity to electrical interference, while its capabilities are sufficient even to work with multi-channel audio. Among the shortcomings, it is worth noting the high price of connecting cables, as well as the need for careful handling of them.

— Under the microphone. Input for connecting a microphone to an audio system; can use different types of connectors (3.5 mm mini-Jack, 6.35 mm Jack, etc.). This function is mandatory for models with karaoke (see "Advanced"), but can be used for other purposes.

— Instrumental. Connectors used to connect musical instruments (acoustic or bass guitars, keyboards, etc.). Most often they are made in the form of 6.35 mm Jack format sockets. The audio signal from pickups has its own specific characteristics, so the instrument input typically features a higher input level and special impedance matching to ensure optimal sound quality.

Audio system operating time without connection to an external power source (network or USB port, depending on the capabilities). Note that manufacturers tend to indicate battery life in their specifications under optimal conditions for energy saving: at low volume, without using additional functions, etc. Therefore, in fact, this indicator may be noticeably lower than the claimed one, and speakers with a long operating time will not sound at full volume for the specified hours.