At the last meeting we talked about it, how to make the system of AV-all that it can do. And it was regarded as a single unit, a kind of building. However, every building should have a proper foundation. Its role in the complex plays AV-woofer. After all, nothing gives your home theater more charm than a deep, powerful bass. Know how the law of meanness? Here is an example. Having spent a bunch of hard-earned money on a home theater system, you buy the newest gunman. Invite all friends and acquaintances "treat yourself" achievements of cinema and computer graphics ... But, alas, your efforts are in vain. What's the matter? Well, at least that the explosion at the beginning of "Lethal Weapon 2" is more like dry twigs crackling underfoot unlucky trapper from some parody of a western, and the pace of the tyrannosaur "Jurassic Park" - timid little steps to baby. And after a sip of beer one of your friends in a fit of drunken candor admits: "Yes, surround sound is fine, that's just not enough bass ..." And that you like salt on the wound and you feel like an idiot - and are willing to pay for half of my life this is the bass.
"Oh, bass, how much in it for the sound of worlds hearts! .." That it considers most lovely films (especially beginners), rests the real sound.The rest, according to them, - nonsense. To hell with the localization and natural tonal balance. Loud, powerful, deafening bass - that "clings" amateurs in full home theater system. Whether it's a shot from a gun in John By, the explosion in the last series "Die Hard", taking off rumble of "Apollo 13" or sounds of an orchestra, performing gavotte in "Sense and Sensibility" - really good bass is the foundation of all sound, endowing it with life-giving drama and the ability to influence, possible only in the best theaters.In the evolution of the human ear is tuned in a certain way. That is why our hearing is most sensitive in the midrange, to which the speech and other sounds of people (for example, a baby crying). In antediluvian times low, rumbling sounds meant danger (earthquake, storm. Growling giant beasts with sharp fangs, etc.), so they now cause the body to secrete adrenaline. Thus, our love for deep bass - it's actually love the thrill.But there is also another explanation overuse bass. As a rule, "hurt" people start home theater after attending relevant exhibitions or shopping salon, and there is usually a sub cut in the whole hog - to produce killer impression on the visitor. Many people think that just has to be at home.
Sounds are vibrations in the air. Causes them all, which can cause the air in motion - from the atomic bomb to the vibrations of a mosquito wing - and, of course, speaker cone vibrations. Electrical signals cause it to move forward or backward. With every movement compresses the diffuser or dilution air, and this compression / vacuum propagates at the speed of sound. The faster it occurs, the above sound. Pitch (or frequency) is the number of cycles of compression and expansion in the second. They are called hertz (in honor of the famous German physicist Heinrich Hertz, rather than Herzen, who, in the words of Lenin, the Decembrists awakened).We perceive sounds are in the range from about 16 Hz to 18,000 Hz (18 KHz). Meanwhile, most of the manufacturers of speakers lead easier to memorize the range 20 Hz - 20 kHz, although sounds above 18 kHz captured only dogs, bats and people who rarely leave their homes silence. Unfortunately for men, the highest part of the spectrum is no longer available for us in the transition to adulthood, with the purchase of the first tube of aftershave, while women in middle age and retain the ability to hear high frequencies well. But on the opposite end of the spectrum, most people there is no problem: even the old distinction frequencies below 20 Hz.The second, and last, physical factor, important for hunters deep bass is a logarithmic quantity - decibels (dB). Decibels, among other things, show the sound pressure level. True, there is a catch: this level measurements are not absolute, but relative. Worse, when the sound pressure level of our hearing changes its sensitivity. However, there is a standard decibel scale, which is taken as zero threshold of hearing, and for the maximum - the so-called pain threshold (it exceeds the threshold of hearing is about ten million times and is 140 dB). Perhaps this is an over-simplification, but if we remember that for most average amateur home movie norm - 75 - 100 dB and that according to this scale, the addition of 6 dB means a doubling of the volume of the rest can be forgotten.
Asset or liability?
To get a real bass in a home theater, you want a subwoofer that is woofer. It can be embedded either in two front speakers, either in their stand, and can be a single device capable of installation almost anywhere in the room as deep bass - omnidirectional sound radiation.Thanks to the last factor eliminates the need for a stereo pair of subwoofers: To get the sound of excellent quality is often only one. It's all clear.The problem lies elsewhere. What should be the subwoofer - active or passive?Passive subwoofers are usually designed for a specific set of speakers and usually addressed to the market economy system. Their main advantage is that they allow you to use smaller main speakers (satellites) and do not require the presence of additional main amplifier outputs. The most serious drawback of passive constructions is their inability to reproduce the elementary enough deep bass. However, sometimes the blame should not subwoofer and amplifier, which lacks "silenok" to shake and satellites, and a subwoofer. That is why the company for several years Technics produces not only a five-, six-channel amplifiers but also for home theater equipped with the expectation of connection is inexpensive passive subwoofer (the last example - model SA-AX7. Considered by us in number 3/2000 on page 79 ).Active subwoofer has a built-in amplifier and controls that allow to change the volume and cutoff frequency, which allows the unit to coordinate with any pair of main speakers. The advantages of active passive subwoofer before - car and small truck. Since in this case the amplifier built-in, it is optimal for a particular speaker, which eliminates many potential problems. Active models improve the sound of any speakers, so you can not change the past, and the existing regulators allow taking into account the specific features of your room. Two shortcomings - relatively high cost and the need for the individual output of the amplifier. Recently, however, prices have dropped significantly, and if your home theater yet active subwoofer, then you are behind the times.
Where lay the foundation?
remind you once again: no matter how well designed acoustically nor was your "cinema", he willy-nilly become a kind of equalizer, reinforcing one frequency and weakening others. This effect is determined by the resonant frequencies of the premises (in fact the acoustic properties determined by the space much larger number of factors, but in this case the simplification not affect the essence of the problem), which in turn depend on the length, width and height. The fact that the room in sound reproduction are constant regions of high and low sound pressure (standing waves). No prizes for guessing that the definition of the optimal place for a subwoofer (as well as the spectator seats) produced either by trial and error, or requires the use of enormous computing power and graduate in the field of acoustics.Optimal location of subwoofer is try to distance it from the TV, so it does not affect the picture tube.
Decent option for oblong room - if you can put the subwoofer at least a couple of meters from the site viewers. General advice: put the subwoofer away from the audience, but not to the corner (aka anything not guilty).Trial and error method is very simple but it takes a lot of time. Put the disk or tape with the deep bass that you can only find, and play it, rearranging the subwoofer from place to place. After each permutation sit in "the viewing" chair and rate occurred with the sound changes. If you are still in doubt, take the basis of the manufacturer's recommendations. When you come to the conclusion that there's nowhere better, check out some movies, make sure you are on track, and then enjoy the results. However, let me give you some "subtle observations of life." First, most beginners either cut in theater subwoofers on the volume too high, or "putting on" the cutoff frequency. In short, if it appears that the sound in the film "The Piano" is more suited to a tape "Terminator 2" or the subwoofer emits fierce growl when playing the bass note of the most modest, turn down the volume. Secondly, if possible, try to arrange the sub around the same wall where the TV stands, to avoid phase shift LF waves from the rest. Third, leave some space between the TV and subwoofer, as the latter are hidden inside large and destructive for the magnets. Fourth, most of the recommendations given by manufacturers AV-amplifiers and processors, in my opinion, incorrect. These devices are usually equipped with linear "subwoofer" output, which is supplied with prefiltered through a low-pass filter signal. Meanwhile, the active subwoofer is equipped with a line input on the same filter. As a result, when you connect two signal by linear low-pass filter are connected in series, and the total response is simply unpredictable. Best served in a special "high-level" full-range subwoofer input signal "columnar" amplifier output. One last tip (it only applies to those who are quite desperate): Setting feeble subwoofer in a corner of the room can be a little "pull" the middle and upper bass.
Bass Wisdom Bass
What do we mean by this word? The answer will have to look in the Hi-Fi-field, in fact it is the ancestor of a home theater. It turns out that the bass are divided into three octaves, and overlapping. By the octave from 20 Hz to 40 Hz are deep bass (here come the lowest organ notes), the octave from 40 to 80 Hz is known as mid range (they are extracted from the bass drum), and the octave from 80 to 160 Hz range is called high bass ( Hear cello and bassoon). Everything below 20 Hz. we feel more than hear, here you will not be able to distinguish the pitch or sound repeated, of course, if you do not live in the Cathedral.
Friendly
Actually this fad bass terminology. The word "attack" is not quite appropriate, and is used because low frequencies are more slow transients compared with the top. Meanwhile, the difference between "slow" and "fast" sounding bass systems, often in another not definable, is the difference between the "pecking on the brain" and forced to listen spellbound.
Most adjectives that describe a good bass. can be used as compliments skillful drummer word, it means the opposite, concepts associated with obesity and sluggishness. So, if the sound of the explosion to mind the definition of "fast", "clear", "clean", "live", "stressful", "tight" or "fine" - perhaps you are dealing with a decent system if the I recall the words "hollow", "bold", "overloaded", "fat", "loose", "fuzzy", "slow", "quiet" or "deaf" - it's time to "go away leg."
Weight category:
When it comes to the amount of something, such as the bass, and we want to use the term "weight". If the system lacks bass, it's called "lean" and "skimpy". And if the bass in excess, say the sound of the complex "bold" and "inflated". When the bass is OK, the system is called "pull" and "muscular".
Dynamics
If the system is able to discriminate between loud and quiet bass notes, and does not sound "like out of a barrel," then apply to it used the word "cotton", "bang" and even "energy" - all in a positive sense. Surprisingly, there are no negative characteristics. I'll try to come up with something myself. How would you like, say, a "sounds. Chews like glass"?
Depth
Speaking of subs, commentators often use the term "deep bass." This means only how "deep" the lower limit of the frequency range. The system is not able to reproduce the deepest bass tones, called "slaughtered", and one that it can, is the proud title of "extended".
Overlap
Each set of speakers, including a "beeper", midrange and woofer, there are points of the frequency range, where the imposition of a single speaker surround sound on the other. They are called points of overlap. So if the speaker midrange "clipped" at 90 Hz. and the subwoofer has a range of 40 to 150 Hz, then somewhere in the region of 100 Hz most of the sound moves from speaker to the subwoofer midrange. This frequency is called frequency overlap. Most speakers are equipped with circuit components which emits a signal that allows a smooth transition from one speaker to another. This scheme is called crossover or crossover.
Bass - to taste
Without quality bass impossible any home theater or audio system worthy of attention ... If you decide to purchase a sub, go to his choice with full responsibility. Unsuccessful model becomes almost useless when it comes to playing bass - better to spend money on a pair of larger and better main speakers. Fortunately, just overwhelmed with lovely shops subwoofers for every taste and for any price, just reach out.
Model for less than $ 400
Energy e: XL16 ($ 300). Although not a very high price, it includes a 40-inch woofer and a 300-watt amplifier MOSFET. Crossover reconstructed on any frequency in the range 50 - 100 Hz. and, if desired, you can connect an external EQ or active filter, for which there is a separate entrance. To facilitate coordination with the rest of the acoustics provided phase control in a very wide range (from 0 to 180 deg.).This subwoofer is not a lot of competitors, and they are designed for either a midi-systems (Aiwa TS-W5), or cost about 35% more expensive (Velodyne CT-80). Those who are on a tight budget, I would advise to buy the main speakers as large as possible, but if you have a small room and you recently purchased a new compact speakers, e: XL16 - what you need in most cases.
<$ 600
REL Q-50 ($ 500). Today it is the most inexpensive production model REL. It is unpretentious, but reproduces deep bass very well. Her closest rival, more elegant in appearance KEF 20B (also $ 500), comes with an integrated 70-watt amplifier and unlike 0-50 is magnetically shielded. Decent bass also demonstrates the company PSW120 Polk ($ 480). He is somewhat preferable due to better quality / price as cause rumble in the power of any home theater system.
<$ 900
REL Q-100 ($ 850). Beautiful, deep bass, good quality / price ratio, acceptable appearance and a big name - that combines this unit. He is able to reach such depths of bass that your home theater system and zagrohochet growl. However, it should warn REL she had here are formidable opponents in the face of exquisite Tannoy 625 ALFie ($ 900), unpretentious, but bass Mission 75AS ($ 800), and small in size but great in all other M & K VX-7B ($ 675). Each of these models is quite a decent alternative.
When the price does not matter
Be careful, very careful. "Price does not matter" - these four short word can mean for the designer more than anything else. If you absolutely need the best in the world subwoofer, carefully examine the possibility of REL Studio ($ 4000), M & K MX-100 ($ 2,200), KEF AV1 ($ 3500), Revel Sub 15 ($ 2800 - 5200), as well as models of firms B & W, Bag End, Linn, Meridian and Muse. The cheapest of these subwoofers lighten your wallet at least $ 2,000, but if you really want to overspend, and you can spend twice as much. In that case, if you need to save your money and place note EnergyMicrostar 12.1 ($ 1600). This cube with a side of 40 cm can bellow so that not seem a little - his half kilowatt power! Kevlar woofer digital amplifier, plus all sorts of bells and whistles sound and custom make it very attractive for high-end theaters. In the UK, one of the masters of bass company occupies a special position - it is not one, but several heads above the rest. This REL.Perhaps no one manufacturer of subwoofers was not met here also welcome and not won so many prizes. Why is this so and who is the creator of success REL? Look at the end of the eighties. A man named Richard Lord gets retired with full honors. And instead of having to start the regular life and rest on our laurels, Richard Lord let his savings to develop and create the simplest woofers for Hi-Fi-Systems. Thus was born the first subwoofers REL. Of course, conservative by nature Hi-Fi-industry refused to recognize the usefulness of such devices, and formed the view that they are not even devilish offspring, but only slightly better. Therefore, in early 1990 the dream of Richard Lord of bass on bass everywhere, seemed distant. Fortunately, life suddenly burst into a home theater, need bass in the oceans, and a place in the history of the REL was determined. REL formula is simple, but devastatingly effective. Each subwoofer has a large subwoofer, heavy, "stocky" body and a power amplifier MOSFET. capable of receiving a signal of a corresponding linear amplifier output or directly from the "columnar" outputs. Regulators for the subwoofer quite a bit - they control only the volume, cut-off frequency and phase. About the latter can safely forget after the initial installation.There are also four "heel" hindering jerking machine, whatever stood on top of him. - So that the subwoofer is more like an impromptu table than on the AV-part system. The formula remains the same at all levels of REL-hierarchy: each simply "superior" model of larger, more powerful and better. Most subwoofers other companies omitted, at least. one of the elements of the formula REL and often this is done in an attempt to keep a lid on the retail price. This approach inevitably leads to lower quality and product turns into another mediocrity. Abandoning such compromises, REL provides his family more and more popularity. Finally, we should not forget that REL is so successful in Russia as a real competitor to its products can make mostly American vehicles, and stay as a solid person, the subwoofer across the ocean is costly. Meanwhile, the United States produced a lot of very cool subs (firms Miller & Kriesel, Bag End. Muse and others), and if not for transport costs, we would recommend them to you more aggressively.
Original sourse of whis article cxem.net
