Comparison Yamaha NS-51 Set vs Yamaha NS-PA40

— Active. Acoustic systems equipped with their own built-in power amplifier. A line-level signal (from the preamp) is sufficient for these speakers, making them extremely easy to use. On the other hand, the built-in amplifier requires power, so these speakers have to be plugged into an outlet as well.

— Passive. Speaker systems that do not have a built-in power amplifier. Accordingly, you need to connect such speakers to an external amplifier (or a device that has such an amplifier — for example, an audio receiver), while paying special attention to component compatibility. On the other hand, passive acoustics are considered more suitable for creating high-end audio systems than active ones: it allows you to choose a power amplifier of your choice, moreover, there are no “extra” electronics in the speaker cabinet, which reduces the likelihood of interference.

— Passive / active. Acoustic systems combining passive main speakers with an active subwoofer. For a number of technical reasons, active subwoofers are more convenient than passive ones: in particular, they save the user from having to look for a specialized low-frequency amplifier, and they provide more tuning options (the latter can be useful for “fitting” sound into a particular room). Therefore, many manufacturers produce passive-active kits.

— 1.0. Single-channel(monophonic) audio system. "Alone" such speakers do not provide a sense of surround sound, but can be used as separate components for multi-channel surround sound systems.

— 2.0. Normal stereo sound: two speakers responsible for the left and right channels. Allows you to create a minimal illusion of "surround" sound by simulating the displacement of the sound source in the space in front of the listener.

— 2.1. A dual speaker system that creates a minimal illusion of "surround" sound, and a subwoofer that delivers powerful and rich sound by adding bass and ultra-low frequencies.

— 3.0. System of three speakers(centre and two front). According to some manufacturers, such systems in small rooms are capable, with some tricks, of reproducing full surround sound without rear speakers.

— 5.0. A set of five speakers(two front, centre and two rear), which allows you to reproduce a full surround sound, which is subjectively perceived by the listener not only in front, but also behind him.

— 5.1. A set of five speakers and a subwoofer for low and ultra-low frequencies, allowing you to reproduce a full surround sound, which is subjectively perceived by the listener not only in front, but also behind him. 5.1 systems ar...e one of the most popular multi-channel audio formats, widely used, in particular, in home theaters.

There are also much rarer options due to narrow needs:

— 1.1. Systems in the form of a subwoofer, on which a general range speaker is installed on top. They are found mainly in concert acoustics — it is convenient to assemble systems for powerful and rich sound from such components.

— 2.2. Further development of the idea embodied in systems 1.1 (see above); in fact, these are sets of two identical speakers of 1.1 format. Such sets are produced from the considerations that for concerts, especially in relatively small rooms, it is often enough just a pair of 1.1 speakers; it is more convenient and often cheaper to buy two such speakers at once than to buy them one at a time.

— 3.1. A system of three speakers (centre and two front), as well as a subwoofer for bass and ultra-low frequencies. It is a "stripped down" version of the 5.1 system; according to some manufacturers, such systems are capable of reproducing full surround sound in the absence of rear speakers, due to which they are perfect for installation in small rooms where it is not possible to place full-fledged 5.1 acoustics.

— 4.0. A variation of 4.1 systems (see below), devoid of a subwoofer, otherwise completely similar.

— 4.1. Simplified version of 5.1 format (see above); such systems usually lack either a centre or one of the rear channels. Anyway, other things being equal, they are cheaper than full-length 5.1, but their sound quality is significantly lower.

— 4.2. This category includes mainly concert acoustics (see "Intended use"), which is an extended version of the 2.2 described above. In 4.2 systems, not one, but two total range speakers are installed above each subwoofer. Thus, you can achieve better and richer sound.

— 5.2. A variation of the 5.1 described above, supplemented by a second subwoofer — this has a positive effect on the quality and accuracy of bass reproduction. On the other hand, setting up such systems is somewhat more complicated.

— 6.1. Extended version of 5.1 format: two front speakers, a centre speaker, three rear speakers (left, right and centre) and a subwoofer for bass and extra bass. It is characterized by a more accurate transmission of surround sound in the rear sector, but is quite rare.

— 7.0. Extended version of multi-channel audio with five main channels (eg 5.1). In this case, the five main channels are supplemented with two more, which allows to achieve a more voluminous and reliable sound. Most often, additional channels are located at the back ("rear right" and "rear left"), but depending on the specific sound format, other installation options are possible — for example, on the sides of the user.

— 8.1. Systems providing 8 main sound channels plus 1 low frequency. The specific distribution of the main channels may be different, depending on the model. However, all 8.1 systems differ, on the one hand, in good reliability of surround sound, on the other hand, in high cost and complexity in setting up.

Speaker sensitivity.

This characteristic is indicated on the basis of how loud the acoustics are capable of producing when a signal of a certain standard power is applied to it. Simply put, the higher the sensitivity of the speaker, the louder it will sound at the same output power of the amplifier. Thus, sensitive acoustics can be effectively used even in combination with relatively low-power "amplifiers". On the other hand, low sensitivity also has its advantages: it allows you to achieve a more uniform frequency response and reduces the likelihood of overloading the amplifier. In the least sensitive modern speakers, this indicator does not exceed 84 dB, in the most sensitive it is 95 – 96 dB or more.

Note that in fact, you have to pay attention to this parameter when acoustics are planned to be used with a separately selected power amplifier. Therefore, for active systems (see "Type"), sensitivity is purely a reference value, and, usually, it can be ignored when choosing.

The crossover frequency provided in the speaker design.

A crossover is installed exclusively in a multi-band model (see "Number of Bands"). This is an electronic filter that ensures the division of the incoming audio signal into separate frequency ranges and directs each range to "its" set of speakers. And the crossover frequency shows where the boundary between these ranges lies. If there are more than two bands, there will be several such boundaries: for example, for a four-band system it may be specified "0.15 / 0.8 / 2.8 kHz" or "0.12 / 1 / 3.8".

In most cases, this parameter has mainly a reference value: the frequencies of the built-in crossover are selected to match the operating characteristics of the speakers installed in the speaker system.

Rated power of one front speaker. See "Total Power Rating" below for details on power rating. Here we note that the higher the power, the louder the system component can sound — of course, with a properly selected amplifier. In addition, this parameter is very important for matching with the amplifier: it is desirable that the output power on the corresponding amplifier channel be less than the power of the speaker. If the incoming signal is more powerful, distortions in the sound and even damage to the speakers are possible, and if it is weaker, then the sound volume will decrease (in other words, it will not be possible to use the full potential of the acoustics), but this moment will be critical only for listening at maximum volume.

Rated output of the rear speaker. See "Front" above for details on power rating.

Rated power of the centre speaker. See "Front" above for details on power rating.

The highest power rating of an amplifier that the loudspeakers can handle safely. Too much input power can damage the speakers, so when connecting, make sure that the amplifier's characteristics do not exceed the capabilities of the speakers. It is worth noting that this parameter may be slightly higher than the total nominal power of the acoustics (see below), since in this case we are only talking about the safety of the equipment, and not about the absence of distortion in the sound.

The total rated power of all speaker components, in other words, the sum of the powers of all speakers. As a nominal one, they usually indicate the highest average (rms) power at which acoustics can operate for a long time without overloads and damage. In this case, individual power surges can significantly exceed this value, however, it is the rated power that is the main characteristic of any speaker.

First of all, the sound volume depends on this characteristic: the more powerful the speakers, the louder the sound they can produce if there is a suitable amplifier. In addition, in passive and passive-active models, compatibility with an external amplifier also depends on the power: the output power of the “amplifier” should not exceed the power of the acoustics connected to it, otherwise overloads and even breakdowns are possible.

Detailed recommendations regarding the choice of speakers for power for a particular situation can be found in special sources. However, in general, an indicator of up to 100 W by the standards of modern acoustics is considered quite modest, 100 – 200 W — average, 200 – 300 W — above average, and the most powerful sets give out up to 500 W or even more.

In conclusion, we note two more nuances. Firstly, when comparing different systems according to this ch...aracteristic, one must also take into account the sound format in which they work. In particular, if there is a subwoofer, it can account for a significant part of the total power — up to half or more. As a result, for example, a 2.1 set of 50 W with a 20-watt subwoofer at the main frequencies will not be able to pull out the same volume as a 40-watt 2.0 system: in the first case, each main channel will have only 15 watts, in the second — 20 watts. Secondly, in multichannel systems, the total power can be distributed among the channels in different proportions; so, say, two 5.1 systems with the same total power can differ markedly in front and rear balance at maximum volume.