Today, if you flirt like a Rolls-Roys with engine power, if you don't show a picture contrast of one in a million, you will be sold under the hammer. Against this background, conservative stereo manufacturers look modest: just think, in the speakers they now indicate the upper limit of 30 kHz, and in the amplifiers they raised the bar only five times - up to 100 kHz. What does all this mean, what was it done for and how to relate to it?
The so-called "high frequencies" have a long history and have entered, one might say, the field of folklore. Anyone who is infinitely far from the torment of listening to the cable is able to make a complaint - "something high is not enough." At the time of magnetic re-recordings, the cherished "prying" was sorely lacking, and what was available melted on the harsh mechanisms of domestic cassette players, like snow in the spring. Almost all amplifiers had two adjustments. Basque was served by a knob about a hundred hertz, and to make everything "sound human", the second band regulator at 10 kHz was twisted to a maximum.
For sophisticated fans to tweak the frequency response, separate equalizers were produced, in which the sliders, as a rule, were ticked, lifting the edges of the range and dropping the middle frequencies. With the included "sadomaso-equalizer" magnetic rerecording was also carried out. Nobody bothered about phase distortions. Today, according to the specifications for the components, the problems with high frequencies are long gone. From myself, I can say that with digital content, at least the characteristics will not disappear anywhere, and the music will sound consistently good. Or consistently bad, haha. So all the same, how to relate to the brisk characteristics from zero to one hundred kilohertz?
According to the rules of good tone, the numbers of the frequency range should be observed and indicated unevenness (in decibels). Not everyone bothers to do this, especially headphone manufacturers sin. The frequency range limits given in the specifications do not say anything by themselves, they only indicate that this device was attached technical signal the so-called "pink noise". It is possible, without indicating unevenness, and the radio receiver can record at least from zero to 500 kHz.
For an adequate, uncolored sound, it is important that the response is as linear as possible, i.e. had the same level on each strip. For amplifiers and sources, the limiting unevenness is plus or minus 0.5 dB, for acoustics - 3 dB.
Since the 90s, in Haifa, tone controls have been removed from harm. And they did the right thing, by the way, although it was in the AU that they would not interfere. When installed in a real room, the speakers demonstrate much greater than 3 dB peaks / dips in frequency response, and advice to even out an ugly sound with a network cable looks like sheer mockery.
It is officially believed that a person is able to distinguish sounds from 20 Hz to 20 kHz. This coincides with the threshold of CD playback - half the sampling rate of a 44.1 stereo signal, i.e. 22.05 kHz. In 24/192 highrezes, the value of the upper limit can theoretically reach 96 kHz, respectively, which in practice no one does: no one wants to sample emptiness, inflating an already considerable file. Currently, both commercial and home-made recordings (eg vinyl rips) in 24-bit / 96 kHz are most popular. Up to 48 kHz frequency range can accommodate anything and anyone. But who will go there?
If you order a hearing test from a district audiologist, then, as a rule, you will receive an audiogram up to 8 kHz, and from above the device will not draw, it is not designed for this. Doctors believe that more than 8 kHz is not necessary for a normal life. The famous so-called "ultrasonic" joke for dogs on the final groove of the 1967 record was recorded at a frequency of only 15 kHz. You can get some test signals and try to hear HF, starting with a dozen. For some it will be an unpleasant surprise to stop at 16 kHz, but don't be in a hurry to get upset.
The famous so-called "ultrasonic" joke for dogs on the final groove of the 1967 record was recorded at a frequency of only 15 kHz With the exception of a wind organ (10 kHz), which also knows how to produce the lowest sounds, no instrument plays above 4 kHz, not even a piccolo flute. Overtones are another matter: they can climb higher - up to 16 kHz for vocals, violin and piccolo. The region is from 14 to 20 kHz and is responsible for creating "air" in the phonogram. And the beloved folk "ticking" of the plates calmly fit much lower - in the range from 7 to 12 kHz. It was all these small numbers that the manufacturers of stereo equipment of the 70s were guided by.
What, then, is in HD recordings over 20 kHz? But you never know what. They say that some previously unaccounted for, and therefore wildly valuable overtones, which a person (especially such a suspicious one as an audiophile) is capable of, if not hear, then feel... If you look at the frequency of the HD track, the picture is different. Someone can see the use of a filter at the same sacramental 20 kHz, and then nothing else. For some, life is observed up to 48 kHz. What could it be?
As a rule - ultrasonic noises of quantization, some kind of resonances, for example, vinyl cartridge systems. Does this mean that audio 24/96 and higher is a deception of the people? It does not mean at all, because we get not only the broadening of the frequency band, but also the removal of quantization errors far away, where they are not heard, an increase in the headroom of the dynamic range. Simply put, HD phonogram is harder spoil when recording, so even vinyl rips at home on 24/96 sound more intelligible and expressive than on the standard 16 / 44.1. So even though we can hear, God forbid, up to 18 kHz, and it is better to listen to music in HD editions. Whatever one may do CDs.
One of the most respected families in audio recording is proud to introduce a new member. We welcome the C314 professional condenser microphone, perfect for both stage and studio. Born from a commitment to absolute precision by the best engineering team, the C314 is made from best materials and components. It went through a demanding design and highly meticulous manufacturing process before reaching the final results: the microphone captures every detail of your creativity with precision. It does not matter where you will record your recordings in a large concert hall or in a small studio room, you need to capture emotions and important moments for you, but just sound. With a full 20 Hz - 20 kHz frequency response and very low inherent noise, the C314 captures every nuance.
Built on the rich heritage of the C414 XLS capsule, its dual diaphragm ensures the highest beam pattern accuracy and its built-in suspension system significantly reduces noise.
The versatile C314 is your live multi-instrumentalist ready to play wherever you need it. Whether it's cardioid, supercardioid, omnidirectional or figure-8, there are plenty of ways to get a more natural sound from any instrument, electric or acoustic guitar, drums, and more. Use a supercardioid to reduce the rumble of drums, then quickly switch to figure-8 for a balanced sound from two vocalists - all with easy access.
The C314 is an excellent partner for any studio, especially those with limited space. As a result, dropping your hands, you can make much more records of the best quality, and if an overloaded signal appears, the LED indicator will immediately inform you. This will help you take full advantage of the huge dynamic range and switch the pad only when needed. This bass filter suppresses vibration, hum, loud sounds and minimizes proximity for balanced recording. The elegant façade of this microphone features a transparent double mesh metal grill that protects the internals and guarantees robust RFI immunity, as well as a robust, scratch-resistant housing that is always ready for transport.
Specifications:
- 1 ”double diaphragm condenser microphone
- Directional Pattern: Cardioid, Supercardioid, Omnidirectional, Figure-8
- Sensitivity: 20 mV / Pa
- Frequency response: 20 - 20,000 Hz
- Resistance: 200 Ohm
- Maximum SPL: 135/155 dB
- Equivalent noise level: 8 dB-A
- Signal to noise ratio: 86dB
- Filter: 100 Hz, 12dB / octave
- Pad: -20dB
- Power supply: 44 - 52 V
- Connector: 3-pin XLR
- Dimensions: 160 x 55 x 43mm
- Weight: 300g
A home speaker system is one of the requirements for convenience. Great sound is the backbone of any entertainment system, whether listening to music. computer games ah or watching a video. Without excellent sound reproduction, even the most gorgeous movie and great game plot instantly fade and seem unfinished. In principle, this is understandable, information is perceived by all senses at the same time, therefore, the low quality of one of the elements instantly affects the general perception.
There are many options for sound output, today we will focus on acoustic systems Oh. When choosing a speaker system for their computer, the user must decide which format is best for him.
To begin with, we will consider a few terms, so as not to dwell on them later.
Satellites (from Latin satellitis - satellite)- speakers in x.1 formats for reproduction of medium and high frequency range of sounds.
Subwoofer- a speaker for reproducing the low-frequency range of sound frequencies (from 20 to 350 Hz). The subwoofer (or bass speaker) is the most powerful speaker in a speaker system and often surpasses all satellites combined in power.
Now let's take a look at the main speaker formats:
2.0 - simple stereo. The system consists of two columns, which are most often installed on a table at the edges of the monitor. Consider the spacing of the speakers and do not place them side by side. The speakers are designed to reproduce mid and high frequencies (two-way), some models can also reproduce low frequencies (three-way).
2.1 - a subwoofer is added to the stereo speakers - a special device for reproducing low frequencies. The placement of the 2.1 speaker system is comparable to the 2.0 configuration, except that the subwoofer is usually located lower (on a special shelf or floor) and away from the satellites. The subwoofer reproduces only low frequencies, while the satellites reproduce high and mid frequencies. The 2.1 system delivers great bass that will not be redundant in games, movies or music.
4.0 - quadraphonic speaker system. This speaker Provides surround sound. The satellites are located in the four corners of the square, while the listener should be in the middle between them.
4.1 - quadraphonic speaker with the addition of a subwoofer.
4.1 volumetric is one of many surround sound formats. Two satellites are located in front of the listener at the edges, between them there is a central channel, another satellite is installed behind the listener. A subwoofer is added to the four speakers, which is installed in front of the listener, but away from the front satellites (most often on the floor).
5.1 is the main acoustic surround format. The structure is similar to the 4.1 format, only two satellites are located behind the listener and they are placed at the edges, not in the center. The feeling created by such a speaker system (for example, when watching a movie) is simply indescribable! Naturally, for correct setting... Indispensable when creating a home theater.
7.1 - the same surround sound acoustics as 5.1, but with big amount channels. More satellites are added to the sides of the listener. Naturally, this makes surround sound even better. Mainly used for home theater applications.
For computer games, 2.1 or 4.1 formats are suitable, stereo or quad speakers are responsible for the main environment, the subwoofer is responsible for low frequencies (explosions, monster voice acting and other low-frequency special effects).
For movie lovers, it is better to choose a 5.1 or 7.1 format speaker. The satellites will create a surround environment (the so-called Dolby Surround, "sound around"), and a separate speaker will be responsible for the output of the voice channel in the film (when viewed with a stereo system, this signal is usually muffled and the voices of the actors are hard to hear).
For music lovers, however, 2.0 speaker systems are recommended, since almost all music is now recorded in stereo. Of course, there are separate 2.1 and 5.1 speakers that will not spoil the sound quality, but there are quite a few of them (jambs with sound, first of all, are associated with a subwoofer, which introduces unnecessary noise and overtones into the sound). Alternatively, you can think about a quadraphonic system, the sound will be really not so much surround as a little unusual stereo.
When we have decided on the format of the speaker system and are ready to choose individual models, it is worth taking a closer look at technical characteristics AC.
Body material
The material that affects the sound quality the most is the material of the loudspeaker cabinet. Modern speaker systems are made from plastic, chipboard, MDF or metal (some premium systems are made from special glass).
- Plastic is used for the manufacture of acoustic systems for the bottom price category... The main advantage of using plastic is the ability to vary the shape and design at a low cost. In this case, there are frequent flaws in the sound, poor reproduction of the low-frequency range, rattling at high volume.
- Wood is an ideal material for making loudspeakers, but it is very expensive (solid wood is used only in the production of luxury loudspeakers). The high cost is associated with the laboriousness of the processing processes, the raw materials must be selected at the cutting stage, kept for a long time and dried naturally.
- Plywood for use in speakers usually has 12 or more layers, has good absorption properties, while being lighter than chipboard and MDF. But, in comparison with the same chipboard and MDF, plywood is a very expensive material, which makes it practically inaccessible for mass production of acoustic systems.
- Chipboard (particle board) is much cheaper than solid wood and plywood. Chipboards with a thickness of more than 16 mm have a high density, which helps to reduce the resonances of the case. Due to its dense structure, chipboard does not introduce its own overtones into the sound of the speaker system. Given the low cost and good acoustic characteristics, particle board is used by many manufacturers for the loudspeakers of the mid-price segment.
- MDF (Medium Density Fiberboard) is a common material in the manufacture of computer acoustics. The main advantages of MDF in the production of speakers are good absorption of sound vibrations and ensuring sufficient rigidity of the speaker cabinet.
- For metal cases, usually aluminum and its alloys are used. They provide good mechanical properties of the case: lightness, rigidity and density. Aluminum reduces resonance and improves high frequency transmission. At the same time, metal, like plastic, makes it possible to bring to life the most daring design decisions. The main disadvantage metal case is too "harsh", "metallic" sound.
None of the materials used in the cabinetry alone provide high-quality sound for your speakers. A huge role here is played by the technical characteristics of the amplifier, filters, speakers, as well as the build quality and tuning of the speaker system.
Power (RMS)
Many manufacturers often indicate in the technical characteristics of their models "music" power (P.M.P.O., Peak Music Power Output), which is determined according to the German DIN 45500 standard.
According to this standard, a short-term signal with a frequency of less than 250 Hz is sent to the speaker system. If there is no audible distortion, the speaker is considered to have passed the test. This does not take into account the nonlinear distortion of the signal. This method allows you to indicate high values of "power", often 10-100 times higher than the maximum sinusoidal. This parameter very weakly characterizes real quality sound playback.
For a more realistic speaker response, an RMS (Root Mean Squared) power rating is used. This power is measured by injecting a 1000 Hz sine signal until a certain level of harmonic distortion is reached. If the characteristics of the model say 25 W (RMS), it means that the speaker system, when a signal with a power of 25 W is applied to it, can work for a long time without mechanical damage to the loudspeakers.
How much power is needed for quality sound? This is determined by the parameters of the room in which the installation of this equipment is planned, the characteristics of the speaker itself, as well as the needs of the listener himself. For a room in a city apartment, for example, a system up to 50 W is more than enough.
Frequency Response (AFC - Frequency Response)
The frequency range is the band of frequencies reproduced by the speakers. In x.1 formats frequency range is divided into two parts - the low frequencies are reproduced by the subwoofer, and the middle and high frequencies are reproduced by the satellites.
The ideal frequency range is considered to be "20 Hz - 20,000 Hz" (with slight rounding, the range of sound vibrations perceived by the human ear). However, in practice, such a range is unattainable by most speaker systems.
In most cases, manufacturers indicate only cutoff frequencies and uneven frequency response. For example, the frequency range "40 Hz - 18 kHz" means that the sound of the speaker system in this range is smooth and reliable. Below 40 Hz and above 18 kHz, the frequency response unevenness increases sharply. Below 40 Hz, the speakers will reproduce sounds indistinctly, there may be a hum or strong signal attenuation, and above 18 kHz, crackling or hiss may appear.
The range value is strongly influenced by the number of bands used by the speakers. Optimum are three-way speakers with active separation of the signal into high-frequency, mid-frequency and low-frequency ranges with the help of, with the subsequent supply of each range to individual speakers of the speaker system. This division allows for independent amplification in different bands of the spectrum and thus provides an optimal mode of operation for each speaker.
Two-way systems are fine for games and movies, but for music playback (especially if you are a music lover and connoisseur of clear sound), it is worth getting a three-way speaker system.
Signal to noise ratio
Signal-to-noise ratio is a value equal to the ratio of the useful signal power to the noise power. Usually expressed in decibels.
SNR shows how much the speaker amplifier makes noise (from 60 to 135.5 dB) if the volume control is turned to maximum in the absence of a signal. The higher the signal-to-noise ratio, the clearer the sound will be from the speakers. Have quality speakers this figure is in the region of 75 dB, for premium models - at least 90 dB.
Acoustic design
There are several options for acoustic design.
Closed box- completely closed housing with speaker diffusers brought out to the front panel. This option has low efficiency and impaired reproduction of the low-frequency range; it requires a rather powerful amplifier.
A phase inverter pipe of a certain length and section is mounted in the body. With the correct calculation of the dimensions of the pipe and the volume of the speaker cabinet, the bass reflex significantly improves the sound of the speaker system. It generates sound wave vibrations in phase with the vibrations caused by the front of the diffuser. Thanks to this, a significant increase in the low-frequency range and "softness" of the sound are achieved. This design is typical for speaker format 2.0.
Band-Pass (closed box resonator)- design for subwoofers. The speaker is installed inside the case, and only the phase inverter pipe is brought out. The speaker itself does not directly participate in the formation of the low-frequency spectrum; instead, it only excites low-frequency sound vibrations, which then multiply in volume in the phase inverter pipe. Band pass is not always suitable for playing music, as at certain frequencies the subwoofer begins to "hum". This is why 2.1, 4.1 and 5.1 systems are not primarily designed for music playback.
Requires a complex and large enclosure. The loudspeaker consists of a small compression-type dynamic head installed in the mouth of the horn, due to which the efficiency of the speaker is significantly increased. The main plus is deep and rich bass. In this case, the acoustics will be massive, heavy and expensive. If you try to reduce the size of the speaker, and therefore the speaker, the efficiency of the system will drop dramatically.
(transmission line) is designed to extinguish and diffuse radiation from the back of the woofer cone. It is housed inside the enclosure and has an outlet just like a traditional bass reflex. The labyrinth allows you to get deep and high-quality bass, and also simplifies the load characteristic of the speaker. An acoustic labyrinth requires a large and complex enclosure, although its use gives only a slight advantage over a well-designed conventional phase inverter.
Omni-directional (omnidirectional) speakers emit sound 360 degrees, which allows you to get a wide and three-dimensional stereo picture. Omnidirectional acoustics are capable of filling a room with sound that will be perceived by listeners almost anywhere. In this case, the sound picture between two such speakers will not be as accurate and focused as in the case of traditional acoustics.
Have electrostatic columns the diffuser that emits sound vibrations is a thin film with an electrostatic charge. This film is so light that it does not accumulate kinetic energy and therefore does not resonate. Thanks to this effect, a transparent and clear sound is obtained, free from coloration and distortion. These speakers are great for vocal and classical music where precision and fluidity are important. The problem is that the open back panel of such speakers requires free placement in the listening room, at a considerable distance from the walls. The speaker requires a power supply and quality amplifier... The limited bass range necessitates the use of an additional woofer or a separate subwoofer.
Magneto-planar speakers by the principle of operation, they are similar to electrostatic, but in them the radiating film vibrates under the influence of the passing sound signal in a constant magnetic field. Magneto-planar speakers sound clear and transparent, and are great for reproducing vocals, including choral parts. Unlike electrostatic speakers, they do not need a power source. The cons are mostly the same. Size, bad bass, need for a good amp.
V tape speakers vibrations of thin aluminum foil in a constant magnetic field are used to create sound waves. The tape radiator reproduces sound with low distortion, but is absolutely not suitable for work in the low frequency range. Aside from poor bass, another problem with ribbon speakers is the slight metallic sound.
Column sizes
Compact shelf acoustics (~ 25 cm high)
Bookshelf speakers are inexpensive, compact, and can provide decent sound, at least stereo. Usually have a neutral tonal balance.
The main disadvantage is shallow bass. In addition, shelf speakers have low sensitivity and in order to get from them loud noise requires at least 40 W of power input. On the other hand, when too much power is supplied, audible sound distortions occur (in the very bad case, the voice coils heat up and burn out).
When placed close to the wall, it is necessary to choose speakers with a bass reflex on the front panel. Among other things, this placement will allow you to reinforce the bass to some extent.
Rackmount speakers of medium size (~ 35 cm high)
Rack acoustics are more volumetric shelf speakers and is capable of providing already very deep low frequencies (the range of sounding of stringed bass instruments). Acoustics of this class represent a good compromise between size and sound quality.
The main disadvantage is the large size for placing them in the workplace or bookshelf. If you use special stands, then such a system will take up space like large floor-standing speakers.
Compact floor-standing acoustics (~ 100 cm high)
Floorstanding speakers can produce bass that is already convincing and deep enough to shake the floor in your living room. With a relatively modest height, compact floor-standing acoustics can have a low-frequency range below 30 Hz. Taking up space like a smaller rack-mount speaker, the floor-standing models deliver better sound, greater sensitivity, and do not require a heavy-duty amplifier.
The main disadvantages are associated with the dimensions of the floor-standing speakers. By itself, such a system will look massive in a small room, and for better sounding the speakers will have to be moved away from the walls (which makes them stand out even more in space). In addition, floor-standing speakers must be well anchored to the floor so that there is no additional vibration in the cabinet.
Large floor-standing acoustics (more than 120 cm high)
Large floorstanding speakers can operate at high power input and have deep bass. Several woofers can be built into the column to expand the low-frequency range. Large floor-standing acoustics have high sensitivity and, even with a low input power, are capable of high-quality sounding of a room of considerable size, sound large-scale and comfortable, have low distortion in bass and a wide dynamic range.
The massiveness of such systems can attract attention, especially if the room is not that big. And they are, to put it mildly, not cheap.
January 2015 Speaker Top List
Stereo systems - 2.0
- Material - MDF
- Full Music Power - 24W
- Frequency Response Range - 70 Hz - 24000 Hz
- Overall dimensions - 226 x 197 x 140 mm
- Speaker weight - 4.75 kg
- Color - black, brown
- Material - MDF
- Full Music Power - 30W
- Frequency Response Range - 63 Hz - 24000 Hz
- Signal-to-noise ratio, dB - ≥ 85
- Magnetic shielding - yes
- Overall dimensions - 220 x180 x140 mm
- Speaker weight - 6.8 kg
- Color - black, brown
- Material - MDF
- Full Music Power - 42W
- Frequency Response Range - 75 Hz - 18000 Hz
- Signal-to-noise ratio, dB - ≥ 85
- Magnetic shielding - yes
- Dimensions - 234 x 196 x 146 mm
- Speaker weight - 4.9 kg
- Color - black, brown
- Material - MDF
- Full music power - 50 W
- Frequency Response Range - 45 Hz - 24000 Hz
- Magnetic shielding - yes
- Overall dimensions - 160 × 255 × 200 mm
- Speaker weight - 5.2 kg
- Black color
- Material - MDF
- Full Music Power - 124W
- Signal-to-noise ratio, dB - ≥ 85
- Magnetic shielding - yes
- Overall dimensions - 218 x 370 x 292 mm
- Speaker weight - 16 kg
- Black color
- Material - MDF
- Full Music Power - 100 W
- Signal-to-noise ratio, dB - ≥ 85
- Magnetic shielding - yes
- Overall dimensions - 210 x 270 x 361 mm
- Speaker weight - 13.7 kg
- Color - black, brown
- Material - MDF
- Frequency Response Range - 50 Hz - 20,000 Hz
- Magnetic shielding - yes
- Overall dimensions - 214 x 575 x 323 mm
- Speaker weight - 21.9 kg
- Color - black, brown
- Material - MDF
- Full Music Power - 140W
- Frequency Response Range - 40 Hz - 20,000 Hz
- Signal-to-noise ratio, dB - ≥ 85
- Magnetic shielding - yes
- Overall dimensions - 258 x 463 x 320 mm
- Speaker weight - 27.8 kg
- Black color
Three-component acoustics - 2.1
- Material - plastic
- Full Music Power - 48W (2x9W + 32W)
- Frequency Response Range - 50 Hz - 20,000 Hz
- Signal-to-noise ratio, dB - ≥ 80
- Magnetic shielding - yes
- Overall dimensions of the subwoofer - 248 x 199 x 294 mm
- Dimensions of satellites - 69 x 234 x 118 mm
- Speaker weight - 4.1 kg
- Color - black, white
- Material - MDF
- Full music power - 80 W (2x20 W + 40 W)
- Frequency Response Range - 35 Hz - 25000 Hz
- Signal-to-noise ratio, dB - ≥ 85
- Magnetic shielding - yes
- Overall dimensions of the subwoofer - 265 × 265 × 265 mm
- Overall dimensions of the satellites - 120 × 202 × 125 mm
- Overall dimensions of the amplifier unit - 69 × 200 × 220 mm
- Speaker weight - 7.5 kg
- Brown color
- Material - MDF
- Full Music Power - 53W (2x9W + 35W)
- Frequency Response Range - 55 Hz - 18000 Hz
- Signal-to-noise ratio, dB - ≥ 85
- Magnetic shielding - yes
- Dimensions of satellites - 90 x 180 x 130 mm
- Speaker weight - 7.8 kg
- Black color
- Material - MDF (subwoofer), plastic (satellites)
- Full music power - 200 W (2x35 W + 130 W)
- Magnetic shielding - yes
- Overall dimensions of the subwoofer - 303 × 264 × 282 mm
- Overall dimensions of satellites - 116 × 195 × 135 mm
- Speaker weight - 8.3 kg
- Black color
- Material - MDF
- Full music power - 140 W (2x35 W + 70 W)
- Frequency Response Range - 20 Hz - 20,000 Hz
- Signal-to-noise ratio, dB - ≥ 85
- Magnetic shielding - yes
- Dimensions of the subwoofer - 274 x 309 x 468 mm
- Dimensions of satellites - 116 x 203 x 160 mm
- Speaker weight - 19 kg
- Black color
Six-channel systems - 5.1
- Material - MDF
- Full Music Power - 65W (5x8W + 25W)
- Frequency Response Range - 30 Hz - 20,000 Hz
- Signal-to-noise ratio, dB - ≥ 75
- Overall dimensions of the subwoofer - 190 x 267 x 400 mm
- Dimensions of satellites - 95 x 218 x 103 mm (center), 198 x 106 x 103 mm (side)
- Speaker weight - 10 kg
- Black color
- Material - MDF
- Full Music Power - 80W (4x8W + 10W + 38W)
- Frequency Response Range - 45 Hz - 18000 Hz
- Signal-to-noise ratio, dB - ≥ 85
- Overall dimensions of the subwoofer - 232 x 242 x 288 mm
- Dimensions of satellites - 180 x 90 x 130 mm (center), 90 x 180 x 130 mm (side)
- Overall dimensions of the amplifier unit - 78 x 255 x 250 mm
- Speaker weight - 12.6 kg
- Black color
- Material - MDF
- Full Music Power 270W (5x32W + 110W)
- Frequency Response Range - 20 Hz - 25000 Hz
- Signal-to-noise ratio, dB - 92
- Overall dimensions of the subwoofer - 267 x 340 x 310 mm
- Dimensions of satellites - 122 x 220 x 182 (small), 240 x 1000 x 200 mm (tower), 220 x 122 x 182 mm (center)
- Speaker weight - 33.5 kg
- Brown color
- Material - MDF
- Full Music Power - 500W (5x67W + 165W)
- Frequency Response Range - 35 Hz - 20,000 Hz
- Signal-to-noise ratio, dB - ≥ 95
- Overall dimensions of the subwoofer - 280 × 318 × 292 mm
- Overall dimensions of satellites -99 × 92 × 163 mm
- Speaker weight - 12.7 kg
- Black color
- Material - MDF
- Full music power - 540 W (5x60 W + 240 W)
- Frequency Response Range - 42 Hz - 20,000 Hz
- Signal-to-noise ratio, dB - ≥ 85
- Overall dimensions of the subwoofer - 367 x 397 × 489 mm
- Dimensions of satellites - 316 x 117 × 157 mm (center), 116 x 203 × 160 mm (side)
- Speaker weight - 30 kg
- Black color
Repeatedly. It is usually accepted that a person hears up to about 20 kHz, and then in his youth. But the real trouble awaits with measurements. Let me give you an example with my hearing.
For a very long time, I have only once (traditionally it is very, very good if the measurement is made up to 16 kHz). I have never seen more. Well, due to the fact that I did not get to a glorious place in St. Petersburg, and it was difficult for a random person to stand still there, then I, like many, could only roughly imagine what my hearing was.
I have already noticed many times that many programs, generators of sinusoidal oscillations of the required frequency, are ultimately not audible due to the peculiarities of the operation of devices in operating systems on computers: the driver cuts high sounds. I was somehow amazed that on an old laptop I could easily hear 20 kHz, but on a new one and with a different program I can't really hear 17-18 kHz.
So now to the point. In stock my favorite, for more than 10 years, the Koss Porta Pro headphones. Their range of reproducibility is often known to everyone: supposedly they can reproduce up to 24 kHz. However, on the Internet there are a lot of tests (frequency response), which indicate a drop in volume of about 20 kHz, so this will affect the results obtained. Unfortunately, it was not possible to find the frequency response above 20 kHz. Also available is the Asus Xonar DX sound card. Sound generator program - NCH Tone Generator.
Based on my feelings, when I did not sleep ideally: up to about 18500-19000Hz it is audible evenly loudly, after that the volume has to be increased and the difference is clearly audible up to the chapel in the program up to 22000Hz. An interesting fact is that after about 18200-18700 the feeling that the sound rises in tone disappears. Perhaps this sensation arises due to the fact that the difference in the frequency response of the headphones between 12000 and 20,000 is about 30 dB.
It has also been noticed that built-in sound cards often cut sound at frequencies above 18kHz. If the "sinusoid" sounds parallel to something, say, communication on Skype, then it starts to be heard. And in the same way, there are recordings of sinusoidal oscillations, which are cut by the driver during playback and cannot be heard without a serious sound card.
Alas, to be convinced more accurately and transparently to me on this stage does not seem possible. But even this measurement is very indicative.
Sometimes such a measurement is a salvation for people who cannot measure anywhere in their city above 8000Hz with hearing problems, in order to find out what is heard from above. And also just to make sure that you can really hear well, hear above the norm.
Power
By the word power in colloquial speech, many mean "power", "strength". Therefore, it is only natural that buyers associate power with loudness: "The more power, the better and louder the speakers will sound." However, this popular belief is fundamentally wrong! By no means always a 100 W speaker will play louder or better than the one with a specified power of “only” 50 W. The power value, rather, speaks not of loudness, but of the mechanical reliability of the acoustics. The same 50 or 100 W is not sound volume at all published by the column. The dynamic heads themselves have low efficiency and convert only 2-3% of the power of the electrical signal supplied to them into sound vibrations (fortunately, the volume of the emitted sound is quite enough to create sound). The value indicated by the manufacturer in the passport of the speaker or the system as a whole only indicates that when the signal of the specified power is applied, the dynamic head or acoustic system will not fail (due to critical heating and inter-turn short circuit of the wire, "biting" of the coil frame, rupture of the diffuser , damage to flexible suspension systems, etc.).
Thus, the power of an acoustic system is a technical parameter, the value of which is not directly related to the loudness of the acoustics sound, although it is related to it in some way. The nominal values of the power of the dynamic heads, amplifying path, speaker system may be different. Rather, they are indicated for orientation and optimal pairing between components. For example, an amplifier of much lower or much higher power can damage the speaker in the maximum positions of the volume control on both amplifiers: in the first, due to the high level of distortion, in the second, due to the abnormal operation of the speaker.
Power can be measured different ways and under various test conditions. There are generally accepted standards for these measurements. Let's take a closer look at some of them that are most often used in the characteristics of products of Western companies:
RMS (Rated Maximum Sinusoidal power Is the set maximum sinusoidal power). Power is measured by injecting a 1000 Hz sine wave until a certain level of harmonic distortion is reached. Usually, it is written in the product passport like this: 15 W (RMS). This value says that the speaker system, when a 15 W signal is applied to it, can work for a long time without mechanical damage to the dynamic heads. For multimedia acoustics, higher power values in watts (RMS) compared to hi-fi speakers are obtained as a result of measurements at very high harmonic distortion, often up to 10%. With such distortions, it is almost impossible to listen to sound accompaniment due to strong wheezing and overtones in the dynamic head and the speaker case.
PMPO(Peak Music Power Output). In this case, the power is measured by applying a short-term sine wave with a duration of less than 1 second and a frequency of less than 250 Hz (usually 100 Hz). This does not take into account the level of nonlinear distortion. For example, the speaker power is 500 W (PMPO). This fact says that the speaker system, after reproducing a short-term low-frequency signal, had no mechanical damage to the dynamic heads. Popularly, the units of measurement of power W (PMPO) are called "Chinese watts" due to the fact that the power values with this method of measurement reach thousands of watts! Imagine - powered speakers for a computer consume 10 V * A of electrical power from an AC power supply and at the same time develop a peak musical power of 1500 W (PMPO).
Along with Western standards, there are also Soviet standards for various types of power. They are governed by the current GOST 16122-87 and GOST 23262-88. These standards define such concepts as nominal, maximum noise, maximum sinusoidal, maximum long-term, maximum short-term power. Some of them are indicated in the passport for Soviet (and post-Soviet) equipment. Naturally, these standards are not used in world practice, so we will not dwell on them.
We conclude: the most important in practice is the power value indicated in watts (RMS) with harmonic distortion (THD) values of 1% or less. However, a comparison of products even in this indicator is very approximate and may not have anything to do with reality, because the sound volume is characterized by the sound pressure level. That's why informativeness of the indicator "power of the acoustic system" - zero.
Sensitivity
Sensitivity is one of the parameters specified by the manufacturer in the characteristics of acoustic systems. The value characterizes the intensity of the sound pressure developed by the speaker at a distance of 1 meter when a signal with a frequency of 1000 Hz and a power of 1 W is applied. The sensitivity is measured in decibels (dB) relative to the hearing threshold (zero sound pressure level is 2 * 10 ^ -5 Pa). Sometimes the designation is used - the level of characteristic sensitivity (SPL, Sound Pressure Level). At the same time, for brevity, in the column with units of measurement, dB / W * m or dB / W ^ 1/2 * m is indicated. It is important to understand, however, that sensitivity is not a linear proportionality factor between sound pressure level, signal strength, and distance to source. Many companies indicate the characteristics of the sensitivity of the dynamic heads, measured under non-standard conditions.
Sensitivity is a more important characteristic when designing your own loudspeaker systems. If you do not fully understand what this parameter means, then when choosing multimedia acoustics for a PC, you can not pay special attention to the sensitivity (fortunately, it is not often indicated).
Frequency response
Frequency response (Frequency response) in the general case is a graph showing the difference in the magnitudes of the amplitudes of the output and input signals in the entire range of reproducible frequencies. The frequency response is measured by applying a sinusoidal signal of constant amplitude when its frequency changes. At the point on the graph where the frequency is 1000 Hz, it is customary to plot the 0 dB level on the vertical axis. The ideal option is in which the frequency response is represented by a straight line, but such characteristics in reality do not exist in acoustic systems. When considering the schedule, you need to pay special attention to the amount of unevenness. The greater the amount of unevenness, the greater the frequency distortion of the timbre in the sound.
Western manufacturers prefer to indicate the range of reproducible frequencies, which is a "squeeze" of information from the frequency response: only cutoff frequencies and unevenness are indicated. Let's say it is written: 50 Hz - 16 kHz (± 3 dB). This means that this speaker system in the range of 50 Hz - 16 kHz, the sound is reliable, and below 50 Hz and above 15 kHz, the unevenness increases sharply, the frequency response has a so-called "blockage" (a sharp decline in characteristics).
What is the threat? Reducing the level of low frequencies implies a loss of richness, saturation of the bass sound. The rise in the low-frequency region causes the feeling of booming and humming of the speaker. In the blockages of high frequencies, the sound will be dull, indistinct. Treble rises indicate the presence of annoying, unpleasant hiss and sibilants. In multimedia speakers, the magnitude of the frequency response unevenness is usually higher than that of the so-called Hi-Fi acoustics. All advertising statements of manufacturers about the frequency response of a column of the type 20 - 20,000 Hz (the theoretical limit of the possibility) should be treated with a fair amount of skepticism. At the same time, the unevenness of the frequency response is often not indicated, which can amount to unthinkable values.
Since manufacturers of multimedia acoustics often "forget" to indicate the unevenness of the frequency response of the speaker system, when meeting with a speaker characteristic of 20 Hz - 20,000 Hz, one must keep an eye out. There is a high probability of buying a thing that does not provide even more or less uniform characteristics in the frequency range 100 Hz - 10,000 Hz. It is impossible to compare the range of reproducible frequencies with different unevenness at all.
Harmonic distortion, harmonic distortion
Kg - harmonic distortion factor. The speaker system is a complex electro-acoustic device that has non-linear characteristic gain. Therefore, the signal after passing through the entire audio path at the output will necessarily have nonlinear distortions. Harmonic distortion is one of the most obvious and easiest to measure.
The coefficient is a dimensionless quantity. Indicated either as a percentage or in decibels. Conversion formula: [dB] = 20 log ([%] / 100). The higher the harmonic distortion value, the generally worse the sound.
Kg of speakers largely depends on the power of the signal supplied to them. Therefore, it is stupid to draw conclusions in absentia or compare the speakers only by harmonic distortion, without resorting to listening to the equipment. In addition, manufacturers do not indicate the value for the operating positions of the volume control (usually 30..50%).
Electrical impedance, impedance
The electrodynamic head has a certain resistance to direct current, depending on the thickness, length and material of the wire in the coil (this resistance is also called resistive or reactive). When a musical signal is applied, which is an alternating current, the head resistance will change depending on the frequency of the signal.
Impedance(impedans) is the electrical impedance to alternating current measured at 1000 Hz. Typically the speaker impedance is 4, 6, or 8 ohms.
In general, the value of the total electrical resistance (impedance) of the speaker system will not tell the buyer anything related to the sound quality of this or that product. The manufacturer indicates this parameter only so that the resistance is taken into account when connecting the speaker system to the amplifier. If the speaker impedance is lower than the recommended amp load, the sound may be distorted or short circuit; if higher, the sound will be much quieter than with the recommended impedance.
Column body, acoustic design
One of the important factors affecting the sound of a speaker system is the acoustic design of the emitting dynamic head (speaker). When designing loudspeakers, the manufacturer usually faces a problem in the choice of acoustic design. There are more than a dozen of them.
Acoustic design is divided into acoustically unloaded and acoustically loaded. The first implies a design in which the oscillation of the diffuser is limited only by the rigidity of the suspension. In the second case, the oscillation of the diffuser is limited, in addition to the rigidity of the suspension, by the elasticity of the air and the acoustic resistance to radiation. Also, the acoustic design is divided into single and double acting systems. A single-acting system is characterized by the excitation of sound coming to the listener through only one side of the diffuser (the radiation from the other side is neutralized by the acoustic design). A double-acting system involves the use of both sides of the cone in shaping the sound.
Since the acoustic design of the speaker practically does not affect the high-frequency and mid-frequency drivers, we will tell you about the most common variants of low-frequency acoustic design of the cabinet.
The acoustic scheme called "closed box" is very widely applicable. Refers to loaded acoustic design... It is a closed case with a speaker diffuser brought out to the front panel. Advantages: good frequency response and impulse response. Disadvantages: low efficiency, the need for powerful amplifier, high level harmonic distortion.
But instead of fighting the sound waves caused by vibrations on the back of the cone, they can be used. The most common double-acting system is the bass reflex. It is a pipe of a certain length and section, built into the body. The length and cross-section of the phase inverter are calculated in such a way that at a certain frequency an oscillation of sound waves is created in it, in phase with the oscillations caused by the front side of the diffuser.
For subwoofers, an acoustic scheme with the common name "box-resonator" is widely used. Unlike the previous example, the speaker diffuser is not brought out to the cabinet panel, but is located inside, on the baffle. The speaker itself does not directly participate in the formation of the low-frequency spectrum. Instead, the diffuser only excites low-frequency sound vibrations, which then multiply in volume in the phase inverter pipe, which plays the role of a resonance chamber. The advantage of these design solutions is high efficiency with small dimensions of the subwoofer. Disadvantages are manifested in the deterioration of phase and impulse characteristics, the sound becomes tiresome.
The optimal choice would be medium-sized speakers with a wooden case, made in a closed circuit or with a bass reflex. When choosing a subwoofer, you should pay attention not to its volume (according to this parameter, even inexpensive models usually there is sufficient headroom), but for faithful reproduction of the entire low frequency range. In terms of sound quality, speakers with a thin cabinet or very small size are most undesirable.
