DIY subwoofer: from entry-level to high-end. DIY subwoofer: from entry-level to high-end Horn subwoofer drawings 8 inches

5.0 system for listening with a subwoofer.

I would like to present to your attention a recently manufactured 5.0 system based on speakers manufactured in the USSR. First of all, I want you to get acquainted with the history of the development of acoustic systems and give some recommendations on choosing the type of speaker.

This led to some difficulties, since the development of acoustic systems usually begins with selecting the volume and shape of the speakers to match the parameters of a particular speaker. In addition, the speakers produced in the USSR, with their lightness and richness of sound, had excessive quality factor, which is why it turned out to be impossible to listen to them even in a “closed box” design - a large uneven frequency response and, as a result, a heavy and mushy sound. For reference: the design of an open box can be done in the following options:

1) Absence of a back wall in the speaker system.

2) Using instead a sound-absorbing material stretched over the entire area; I experimentally select the thickness and material.

3) Use a perforated back wall, such as here:

However, the price for a “smooth frequency response” is a sharper decline much further from the main resonance frequency in the low-frequency region. due to an “acoustic short circuit” between the front and rear of the speaker cone.

A way out of this situation was found in the use of a second low-frequency speaker in the front and most important speakers. This made it possible to reduce the lower limit playback frequency to 90Hz and improve the radiation pattern of the acoustic system.
You can compare the frequency response graphs - the top box is open, the bottom box is closed.

The choice of speakers for acoustic systems, due to the high cost of imported speakers, the presence of fakes and Chinese copies, was settled on domestic ones, made in the USSR. They are highly valued in the circles of audiophiles, lovers of tube and vintage sound. Among the advantages you can consider:

affordable price;

High sensitivity (undemanding to the power of the amplifier and ideal for a tube amplifier);

Big potential.

I will dwell on the latter in more detail. Wideband speakers of domestic production had a very pleasant timbre, simply chic and enviable microdynamics and detail in sound for many foreign analogues, a wide stage and lightness of sound. This was achieved due to the absence of vibration and sound-absorbing mastics in the manufacture of the diffuser. Of course, there were some casualties. Now we can highlight the main disadvantages:

Too uneven frequency response due to excessive quality factor and lack of mastic, which is used by imported dynamic head manufacturers to eliminate the above-mentioned shortcomings;

The appearance of most of the speakers, especially the basket, is rather unprepossessing, which is why you have to resort to non-standard solutions such as placing the speaker from the inside of the case or using grill grilles and decorative rings to hide these shortcomings. The choice settled on 8" 8gdsh-1 for the bass/midrange of the front and rear speakers

and 6" 5gdsh-4 for the central channel.

The legendary oval diffuser type 3gdv-1 was used as a high-frequency link, which gives a velvety timbre to the sound of the speakers, unlike dome tweeters.

However, the game is worth the trouble. The inherent potential can be revealed thanks to long and painstaking work on calculating and setting up the separation filters, which took the lion's share of the time in the manufacture of these speakers.

To recreate the correct sound picture in a 5.1 system, the rear speakers must not only be located at a level slightly above the listener’s head, but also be directed strictly at the listener. To do this, I use consoles (brackets) with vertical and horizontal angles of inclination. However, there is a problem: they must be attached to the back wall of the speaker, which we don’t have... Here we had to sacrifice the appearance of the top wall of the speaker, securing them with 2 bolts and slightly modernizing the brackets for mounting to the top of the speaker system.
to secure them from the inside. An attempt to search for CNC machines by milling in the city was not successful, so I had to mill it manually using a template. However, after the work was done, irregularities and chips from the decorative film were revealed. The protective grill grille not only did not give the best appearance, but also worsened the appearance of the joints of the grille with the chipboard body.


To objectively evaluate the sound, the opinion of audio critics is necessary. A panel of critics consisting of relatives and friends was immediately created. Most of them are simply indifferent to music. And only 2 of them are musicians.
The test compositions were the Nigtwish Dark Parsons Play concert from 2008, recorded in DTS-HD Master audio 5.1 and 2.0 format. 24Bit 48KHz with audio bitrate 5400 kbps and concertMetallica: Orgullo pasion y Gloria - Tres Noches en Mexico 2009 with audio track formatDTS-HD Master audio 5.1 and 2.0. 24Bit 96KHz with audio bitrate 7200 kbit/second.
When we first listened to the 5.0 system, we noticed a clear localization of objects, a large-scale stage with an evenly distributed sound field, excellent microdynamics, the playing of each instrument was clearly audible, and most importantly, the reproduced sound images are not tied to the acoustic system, but are evenly distributed in the recreated powerful scene. Even when listening to these concert soundtracks and other single tracks in Flac format(uncompressed audio codec, quality is not inferior to a licensed CD)and watching the trailer for the film Transformers: The dark side of the moon, a very interesting phenomenon was observed: the stereo pair provided such a vast scene that even in a non-ideal room from an acoustics point of view, objects were localized even to the side of the listener and even behind the speakers, which was a very pleasant surprise and put an end to doubts about the correct manufacture and configuration of the speakers.

Modern music and special effects in movies (such as explosions in movie soundtracks) contain a lot of low frequencies. While full-range speakers can have a fairly full range of frequencies, they are complemented by subwoofers that can really reproduce low frequencies clearly, which is especially true for bass-heavy music such as EDM (electronic dance music) or reggae.

Placing conventional speakers is usually a relatively simple matter, but the placement and configuration of subs has several variations and can be more complex. Let's start with the basics.

A subwoofer is a specialized cabinet that reproduces the extreme, lower limit of the frequency range. Studio or home theater models can operate in the range from 20 to 250 Hz; in sound reinforcement, subs typically operate from 30 to 120 Hz, with a crossover point from 80 to 100 Hz. They can be passive, powered by external amplifiers and processors, or active, with built-in amplification and processing.

In smaller systems, the signal to the subs and main speakers is sent from a single, main output of the console, while larger setups may receive low-frequency content only from low-frequency instruments, such as a bass drum, bass guitar, or even a bass vocalist. . In this case, the signal for the sub is sent for amplification through a separate console output (aux, matrix or mono bus). This helps clean up the muddy low-end sound because the low-frequency signal eliminates open mics on stage that suck up stage noise and which may be out of phase with each other.

There are several different types of subwoofers, each design representing a compromise between range, efficiency, size and price. Designs may use one or more speakers arranged in a variety of configurations, including:

Sealed housing.

The speaker(s) are installed in a sealed housing. Although this design handles transients well, compared to a ventilated case, the efficiency is low, and reproduction of the lowest frequencies is quite problematic, especially at high volume levels. One notable exception is a specific design that uses proprietary electronic processing control systems to reproduce low frequencies (down to 20 Hz).

Bass reflex/Ventilated enclosure/Bass reflex enclosure.

The most common type of subwoofer design in sound reinforcement, the "bass reflex" has the speaker(s) mounted in a box that also has one or more vents. The vent (or port) is of a certain size and length so that the sound coming from the rear of the speaker when exiting the box is in phase with the sound coming from the front. The advantages of a bass reflex over a sealed design are many, including: enhanced low-frequency response, increased power and increased sound pressure.

However, these benefits come with increased cost, larger case size and weight, and slow transient response. It is also necessary to use an additional low-cut filter below the tuning frequency to protect the speaker's suspension system from damage at high levels.

Bandpass.

In this design, one (or more) speaker is placed in a resonator chamber, which may be closed or vented, and plays into a second vented chamber located in front of the box exit. By passing through these tuned chambers, the sound is limited in the frequency range, but the output is increased within the frequencies specified by the chambers, along with a reduction in upper harmonics.

The disadvantage is that placing a second resonance chamber in front of the speaker increases the size of the cabinet.

Loaded horn. As the name suggests, the speaker is housed in a closed (sometimes vented) chamber, the output of which is directed through a horn. A horn increases the speaker's output and can also improve directivity, depending on the length and area of ​​the horn's output (the part that extends outward). Because low frequencies require a large horn, designers typically bend, fold, or fold the horn into the cabinet, resulting in a more manageable box size.

DrawingLAB Sub, subwoofer with horn-loaded design.

The horn design offers an increase in level compared to the bass reflex design, but sometimes it does not reproduce the lowest frequencies very well because a significant horn size is required to handle these longer wavelengths. However, they can be stacked in groups for additional low-frequency extension. The large size and weight of these enclosures tend to limit their use for large events.

Back-loaded horn.

The speaker is placed at the output of the horn, one side is directed into the horn, the other - towards the exit from the horn. Mounting the speaker in this location reduces the required travel distance of the speaker mount compared to a normally loaded horn, resulting in less distortion and more output. These benefits come with the increased cost, size, and weight of subs. However, the results can be very good, especially in challenging acoustic environments.

Cardioid.

This design allows for a larger outlet at the front of the drawer and a smaller outlet at the back. This is usually achieved by adding another speaker at the rear of the cabinet and changing their phase relationship and/or output arrival time relative to the front speaker, helping to cancel out the rearward sound waves.

The cardioid design focuses low-frequency energy onto the audience, reducing unwanted reflections and stage noise. These benefits come with greater cost and weight, and additional amplification and processing are required if the subs are passive. However, the results can be very good, especially in challenging acoustic environments.

Hybrid designs.

They use a combination of different approaches within one body. For example, I recently came across one configuration with two speakers sharing a common vented chamber. One front-firing speaker stands straight, while the other stands at a 90-degree angle and emits into a second ventilated chamber.

Also on the market is a cardioid passive subwoofer with two drivers: an 18-inch bass reflex configuration and a 15-inch folded horn.

Obviously, there is a lot to discuss when it comes to subwoofers, and what I have presented here is intended as an example, simply as a primer on which any picture can be painted. A good understanding of how subs work and interact is worth your time, and delivering low-frequency energy with maximum impact and controllability is one of the defining factors of a successful sound reinforcement experience.

Craig Lierman

Horn acoustics

Horn acoustics have always been more expensive than conventional ones. And it is not surprising that the most ardent fans of such acoustics are those users who once owned traditional speakers.
There is nothing surprising about this. A sophisticated listener will always appreciate the overall harmony, integrity of perception and natural sound.
The user himself likes horn acoustics due to its musicality and ability to captivate the listener.

What it is

Modern audio equipment is capable of reproducing the entire range of required frequencies. This may be enough to convey musical compositions, but it is completely insufficient to create a sense of the listener’s presence.
As any music lover will tell you, there is something that is responsible for conveying not just music and melody, but also for conveying the emotions of the performer. Horn acoustics do this job just fine.
Horn acoustics are designed differently from conventional ones. The speaker (see) in it is not very large in size and it is connected to a horn, which increases the volume of its sound.
This can be compared to the case when a person, in order to shout to his interlocutor at a great distance, folds his hands into a megaphone.

Note. If you are thinking about purchasing horn speakers for your car, we hasten to warn you: the difference between good and bad horn speakers is very significant than is observed in traditional options.
Cheap horn acoustics made by an unscrupulous manufacturer cannot serve as a comparison. It was these cheap options that gave rise to rumors that supposedly horn acoustics are good, but the sound in them is colored.

As for high-quality horn speakers, they are always expensive. They always use Alnico magnets and exotic metal diaphragms.
Horn acoustics are always assembled according to strict tolerances and dimensions. In short, such a production technology cannot imply any compromises or cost reductions.

Let's give examples. The two-inch TAD compression driver used in all Cesaro horn acoustics models costs about 1 thousand euros. At the same time, the most expensive tweeter today is the Scan Speak with a beryllium diaphragm and it costs only about $600.

Horn acoustics for cars are always unique products produced in series. The names of some are written in golden letters in the history of car audio.
For example, this is the Japanese horn acoustics Maxonic, produced since 1932. Today Maxonic always presents high-tech products.
When creating, expensive technologies are always used using magnetic systems in emitters.

Story

So:

• It will be interesting to know that the very first loudspeakers in the world were of the horn type. They appeared back in the 20s of the last century.
  The technology for creating it was unique and they simply didn’t know how to make other acoustic systems;
• Ten years later, speakers appear that are already similar to today's versions of traditional acoustics. They immediately gained great popularity, but they forgot about horn acoustics.
  At that time, it was mistakenly believed that the ideal place for horn acoustics would be for sounding large spaces, but it was simply not suitable for pleasant listening to music;
• Another ten years pass and the famous American engineer creates a completely new design of horn acoustics. It was Paul Klipsch (that was the name of the engineer) who proved that horn acoustics would allow the reproduction of musical compositions with very high quality.

Note. It was then that the engineer founded a company for the production of horn acoustics, which to this day is a world leader. The company was called Klipsch, and speakers of this type were called “Clipsch.”

• It’s interesting that music lovers immediately realized that the clips reproduced music in a special way. Since that time, horn acoustics have become the choice of a rather narrow circle of connoisseurs of real music;

• The second half of the last century was marked by the emergence of completely new carriers. In addition, the latest developments and new approaches for processing and amplifying the audio signal are emerging;
• Finally, having reached the apogee of modernization and improvement, people began to understand that the sound could not be given “liveness”. And then the eyes of many turned to horn acoustics, for which a real boom began about three years ago.

The magical sound of horn systems

So:

• It’s not difficult to verify that horn acoustics sound special. And there are all the prerequisites for such a sound. Firstly, horn acoustics are highly sensitive. This makes it possible to reproduce the most subtle nuances and convey the emotions of the performer;
• Secondly, horn speakers produce sound waves that are more “natural” in nature compared to the air vibrations coming out of traditional speakers;
• Horn acoustics can reproduce low frequencies, but their size depends on this. In other words, the lower frequencies you have to reproduce, the larger the size of the horn speaker must be.

Note. It is for this reason that horn acoustics are mostly used to reproduce midrange and high frequencies, but if you choose larger speakers, then the low frequencies will also be reproduced at the highest level.

• And that is not all. Low frequencies will be reproduced not just like that, but at the highest level. True, only the most subtle connoisseurs of sound can distinguish the difference in reproduction.

Note. It is interesting that recently there are quite often speakers where only the HF emitters are made in the form of a horn. For example, the same speakers of the Klipsch Reference series are made according to this model.

• High frequencies reproduced by horn speakers sound much louder. Needless to say, the HF quality is better than when using conventional tweeters.

Recently, among the manufacturers of horn acoustics, I would like to single out the Italian company Zingali. The engineers of this company created an original horn emitter that simultaneously reproduces midrange and highfrequency frequencies, and at the same time looks beautiful.

Horn acoustics in cars

Needless to say, all traditional car speakers do not allow you to achieve high sound quality. The problem is not anything, but the cramped interior.
Horns will give you the chance to significantly enhance the sound and create the effect of presence (as if you were sitting in a studio or at a concert). Everything can be explained simply: a horn increases the distance over which sound waves propagate, while simultaneously increasing the density of sound and imparting a characteristic melody.
Technical solutions for placing such acoustics in a car can be different:

• So, the most popular way is to install a loudspeaker in front, frontally on the wall of the housing, inside which the main waveguide is formed. It has an outlet to the outside;
• Another option involves a horn system with a low-frequency loudspeaker. It is placed in a separate building. The same fate follows the tweeters and midrange speakers, which are also placed in the corresponding housing separately from each other.

Advantages and disadvantages of horn acoustics

This concludes our review of horn speaker systems. Recently, they have increasingly begun to be installed in cars with their own hands, using step-by-step instructions, useful video reviews, drawings and photo materials.
The price of good horn acoustics is very high, but this will not stop ardent music lovers.