On the use of the subwoofer in musical system
Note: it is used exclusively to MUSICAL systems, i.e. systems in which it is assumed listening to music.
What is the subwoofer I think many people know, but not everyone knows the true meaning of this word.
Subwoofer - low-frequency speaker system, reproducing frequencies below those which reproduce working with wideband AC.
Consider how the subwoofer is integrated into the sound-reproducing system.
System without a subwoofer
Initially there is a stereo signal at the output of the source (CD player, DVD, etc). (I'm going to talk exclusively about stereo recording, because the vast majority of them.) So this is a stereo signal is input to a stereo amplifier and outputs the amplified signal is fed to a broadband AC. In this implementation, the audio signal path, the signal passes through a minimum number of components, and in the most pure form is served in AU.
System with subwoofer
There are different options.
In General there may be other options but they all boil down to the fact that the front speakers is either fed a full range signal, or MF/HF component.
Now the former implies the use as front speakers high-power broadband systems, and the subwoofer is used as additional support to the front at the lowest frequencies. In the second case, as the front satellite speakers are used not large size, and power, and bass spectrum of the signal reproduced by the subwoofer. In this approach, one can create a system characterized by a wide frequency range low cost and large size. In such systems, the subwoofer really absolutely need to obtain any acceptable frequency range of the overall system. This solution is typical for budget systems is not high.
Now let's look at what gives us the use of the subwoofer in musical system.
Add to your subwoofer system can significantly increase its dynamic range, lower cut-off frequency, to provide a higher volume level without distortion, and in the case of an active subwoofer to reproduce midrange/high-frequency range due to the discharge of a stereo amp for the front speakers, and the speakers. An additional amplifier and subwoofer system allows to increase the maximum sound pressure level, and removal of the bass signal from the front allows you to enhance the sound of the midrange band, because bass head oscillates with a large amplitude, and the amplifier operates at a lower level signal, as clearly and purely practicing not large levels of MF and HF signals.
Now let's look again (a bucket of tar).
Practice shows that the use of the subwoofer in the sound system often reduces the quality of the sound. This is possible with a poor quality of the subwoofer, or it is not configured correctly for use in a particular system, or the fact that it is designed to play every bass effects, explosions etc in DC systems and not to transmit subtle shades of music.
Now let's think why is this happening?
For a start it is worth noting that the use of the subwoofer always brings tract additional electronics. Not the fact that the filter of the subwoofer will be of high quality, it will introduce additional distortion and noise in the original signal. But this is far from the worst.
The sound quality of the subwoofer may not be initially high. You can certainly suggest the use of quality subwoofer, but there are very few, and they cost a lot of money. Most on the market subwoofers are dull, sluggish, muttering bass. They are clearly focused on the application in the theatrical systems, as the source of LF noise, bukhov and Bach. In that the sound is extremely difficult tapped a clear height of individual notes (usually it's like the bass in this range on a single note) on these subs sound of the bass guitar is not distinguishable from the sound of the bass. Very rare models are musicality, high articulation, clarity of the bass. While broadband quality floor speakers, most of them have these qualities in full measure.
There is a very serious problem of harmonizing the subwoofer and the front speakers. The sound of the lowest sounds reproduced by the subwoofer can be very different in character from the sound of the lower mid and upper bass from the front speakers. The result is a strong homogeneity in the bass range. This is why it is extremely important a harmonized subwoofer as a rule you should use the subwoofers from the same family and that broadband AC, and certainly one manufacturer. This greatly increases the chances of finding the same sounding pair. Of course that the application of high-quality broadband AC such problems do not exist.
The challenge of reconciling the sound levels of the front and the subwoofer is solved easier, but many exceed the volume level of the subwoofer above the optimum, without noticing. This sound quickly tiring, and not all know what happens. In high-quality broadband AC, this problem is solved by itself, projectroot based on maximally flat frequency response.
We should not forget about the problem of phase matching subwoofer with front. Some subwoofers have a phase switch, which this problem is partially solved, but many cheaper models cannot accommodate such adjustments. And not all users can precisely adjust the phase of a signal, clearly noticing the difference between properly configured subwoofer and not configured at all.
The subwoofer filling the room with deep powerful bass can cause the appearance of resonance phenomena, very much spoiling the sound. This is manifested in a louder sounding single notes, bubanee, sluggish and not dynamic, clear sound. It is therefore important to position this source of low-frequency energy. You can't just throw a sub in the corner and hope that he'll survive. In a system with two or more sources of bass this problem easier to resolve, by correct positioning systems not only about space and relative to each other.
All this is compounded by the fact that many tend to install a redundant level of the subwoofer, the sound becomes more powerful, Basilea cooler" and then I hear the job for which they were paid not small money. The highest compliment to the subwoofer will be that of his contribution to the sound can not be heard directly! It should complement the sound of the front speakers without attracting attention. Only in this case it will not spoil the picture of the sound system.
Rare subwoofer does not degrade the overall picture sound system, having a proper, dense, focused, accurate, clear, elastic, fast bass, a well-negotiated with the sound of broadband AC.
And now let us think, and whether to bathe with the choice of subwoofer for your system, overcoming the problems. This will require a lot of time for not hasty thorough, thoughtful occlusive huge number of sets of speakers/subwoofer. Most of the entries really are not in the spectrum of frequencies below, say, 40Hz. No such composition of course there is, but not so much, so you can limit the requirements to lower the cutoff frequency at 35-40 Hz. With regard to the necessary power it is already written, and I will not repeat them, except to say that for a home system even when listening to heavy rock songs in a decent size room is enough power in excess of 100W. The most demanding music lovers who love to listen to classical works may need and all 200W peak. But not many people do. While most contemporary compositions, the dynamic range is lost after mastering, and it is in such compositions is not great, and therefore no need to twist the volume knob until it stops to hear a quiet tone.
And what we notice? Not that exorbitant demands turned out to be our ideal source of low-frequency energy. Most floor systems are not even of the highest class easily meet the requirements. And many solidly designed broadband speakers from top brands, easily outdo any subwoofer in the sound quality. So why bother with the extra hemo**th which will not inevitably appear in the application of Saba? By increasing the level of components making up the pair broadband speakers/sub koenne problems becomes smaller, BUT the quality of the AC increases by so much that is simply not clear why there wormed subwoofer? And in the case of floor-standing speakers of the highest class, all doubts about the need for some assistance for low frequency range just disappear by themselves. (for the most ardent opponents of my approach will lead a concrete example (not for advertising) Legasy focus 20/20. For those who have any doubts after reading this article just suggest that you read the description, and even better test these systems, and I am sure your doubts just will vanish and you will be happy).
This article represents the views of Audiobytes with experience, which I feel and think. Written after reading numerous articles on similar topics, and based on personal experience.
Author: IOSCO Michael aka Misterio; Publication: www.cxem.net