Creating an audio system with 20 speakers in the car, is not just a desire to make something loud, but a complex engineering project bordering on art. Such installations are rarely created for the sake of everyday listening to the radio on the way to work; This is the lot of professional SQ-systems (Sound Quality) or SPL-competitions, where every decibel and hertz are under strict control. The implementation of such a number of emitters requires a deep understanding of the physics of sound, the laws of electrical engineering and competent planning of the acoustic space of the cabin.
The main difficulty lies not in the physical placement of twenty speakers, but in their synchronization and phasing. Uncoordinated work even pairs of speakers can cause frequencies to cancel out, turning powerful bass into a buzz and high frequencies into mush. Therefore, before you start purchasing equipment, you need to clearly understand what role each speaker will play in the overall sound picture.
You will face significant challenges in the areas of energy consumption and installation. A standard 12-volt vehicle on-board network simply cannot withstand the load from a system of such power without serious modernization. To power a system of 20 speakers with a total power of more than 5000 Watts, it is necessary to install an additional generator or lithium iron phosphate (LiFePO4) buffer batteries. Ignoring this fact will lead to a voltage drop, sound distortion and failure of the vehicle electronics.
Concept and zoning of acoustic space
Before drilling holes in door panels or pillars, a detailed concept must be developed. A twenty-speaker system is usually divided into several functional zones: front stage, rear support, subwoofer array and possibly surround or up-firing effects. The front stage is critically important, as it forms the stereo image and localization of instruments.
For the front stage, a three-way design is often used, where each speaker is responsible for its own frequency range. This allows you to relieve each driver and get a cleaner sound. Rear speakers in systems of this level rarely work as an independent source of music; More often they perform the function of creating surround sound or correcting acoustic defects in the interior. It is important to understand that acoustic design each speaker must be individual.
The distribution of speakers throughout the cabin requires consideration of reflective surfaces. Sound in a car is a constant struggle against reflections from glass and plastic. When placing speakers, you must take into account the propagation vectors of the sound wave. For example, tweeters, or tweeters, it is better to point it not directly at the listener, but at the windshield or center pillar to create the illusion of a wide stage.
Use a laser level when marking installation locations. Even a minimal deviation of the speaker axis by 5 degrees can drastically change the perception of the stereo scene at the listening point.
Selecting components: speakers and their types
Selecting twenty speakers is a task for a logistician and an engineer at the same time. You'll need to buy in bulk, which can provide savings but requires precision. Typically, such systems use speakers of different sizes: from miniature 1-inch tweeters to powerful 15-inch subwoofers. For midrange frequencies, speakers with a diameter of 6.5 inches are often chosen, as they have an optimal ratio of cone size and response speed.
Particular attention should be paid to the parameters Thiele/Small, which describe the electroacoustic properties of the speaker. For a 20-head system, it is critical that the speakers operating in the same frequency band are identical. A variation of parameters of even 5-10% between speakers of the same model can lead to them operating out of phase at certain frequencies. Therefore, professionals often buy speakers with a reserve and conduct preliminary testing.
- 🔊 Tweeters (HF): Usually they are installed from 4 to 8 pieces to create a detailed high-frequency picture and airiness.
- 📢 Mid frequencies (MF): The basis of the vocal range, their number can reach 8-10 pieces depending on the switching circuit.
- 🔉 Low frequencies (LF/Subwoofers): To create pressure, specialized speakers are used, often in bass reflex designs.
When choosing, pay attention to the diffuser material. Preferred for SQ systems carbon or multilayer composites that provide rigidity and low weight. For SPL systems, where maximum volume and diffuser stroke are important, reinforced paper or fiberglass is often chosen. Don't forget that 20 speakers is a lot of weight that needs to be secured securely.
Power calculation and selection of amplifiers
A system of twenty speakers consumes a colossal amount of energy. If the average speaker draws 100-200 watts, then the total system power can easily exceed 3000-4000 watts. A standard car generator that produces 80-120 Amps cannot cope with such a load. You will need to replace the generator with a reinforced one (High Output Alternator) with a current output of 250-300 Amps and higher.
To amplify the signal, one or two stereo amplifiers will not be enough. Typically a bridge circuit is used to connect several multi-channel amplifiers or monoblocks. It is important to correctly calculate the load resistance. Connecting 20 speakers requires a complex paralleling circuit to ensure that the resulting impedance on each amplifier channel does not fall below the acceptable minimum (usually 1 or 2 ohms).
☑️ Energy consumption check
Amplifier efficiency also plays a role. Class D is more efficient and heats up less, which is critical when installing many units in a limited space. However, for SQ systems, class A/AB is sometimes preferred for better midrange sound, despite their low efficiency and high heating. The table below shows the approximate power distribution for a typical system:
| Speaker type | Quantity (pcs) | Power 1 pcs (RMS) | Total power (W) |
|---|---|---|---|
| Tweeters (HF) | 4 | 50 | 200 |
| Midrange speakers | 8 | 100 | 800 |
| Midbass (LF/MF) | 4 | 150 | 600 |
| Subwoofers | 4 | 500 | 2000 |
| TOTAL | 20 | - | 3600 |
Don't forget about the amplifier's power reserve. It is recommended that the amplifier deliver 20-30% more power than the RMS of the speakers in order to operate in linear mode without clipping (distortion). Clipping is the main enemy of speaker coils, especially with such a dense installation.
Connection diagrams and crossovers
The organization of signal chains for 20 speakers is impossible without the use of active crossovers or an audio processor. Passive crossovers (capacitors and coils included with the speakers) are ineffective in this case, since they introduce power losses and do not allow flexible adjustment of the cuts. You will need a digital processor (DSP) with at least 8-12 channels, or a combination of several processors.
The connection diagram will look like a complex engineering design. The signal from the head unit (or directly from the DAC) goes to the processor, where it is divided into frequency bands. Each band then goes to its own amplifier channel. For example, all tweeters can be powered by one two-channel amplifier, all mid frequencies from a four-channel amplifier, and subwoofers from powerful monoblocks.
⚠️ Attention: When connecting a large number of speakers in parallel, pay attention to the phasing. If one speaker in a group of four is wired out of phase (plus and minus reversed), it will act as a sound wave “absorber,” canceling out the work of the other three. Phase verification is a mandatory step before final assembly.
Usage active crossovers Inside the DSP allows you to adjust delays (Time Alignment) for each speaker separately. This is critical because the speakers in a 20-piece system are at different physical distances from the listener. Without delay correction, sound will arrive at the driver's ears at different times, destroying the stereo effect.
Why can't speakers be connected in series?
With a series connection, the resistance increases, which reduces the power output. But the main danger is that if one speaker in the circuit burns out, the sound disappears in the entire group. In a 20-speaker system, this means running the risk of being left without an entire frequency band in the middle of a performance.
Acoustic design and installation
Installing twenty speakers requires altering the car's interior. Standard places in the doors will not allow placing such a number of radiators with the correct acoustic design. You will have to make podiums, reshape the door panels, build boxes in the trunk and, possibly, change the configuration of the ceiling or rear pillars. Materials must be durable and not resonate.
For each speaker, it is necessary to create a closed volume (acoustic chamber), unless it operates in open space (which is undesirable for LF). The use of high-density MDF (fibreboard) is an industry standard. It is important to ensure the tightness of the chambers, since even a small air leak reduces the efficiency of the low-frequency section.
- 🔨 Vibration isolation: Before installing the speakers, all metal surfaces of the body must be rolled with vibration-insulating materials at least 3-4 mm thick.
- 🧱 Noise insulation: A layer of sound-absorbing materials (splen, felt) is required so that the sound from the interior does not escape outside, and external noise does not interfere with hearing details.
- 🔌 Cable management: Wiring for 20 speakers requires tens of meters of cable. All harnesses must be laid in a corrugation and securely fastened to avoid chafing and interference.
Tweeters are often installed in windshield pillars or dashboards. To do this you have to cut the plastic and make inserts. The quality of this work directly affects the appearance of the car. Often, for such projects, custom-tailored interiors are ordered, where space for speakers is integrated into the upholstery design.
The quality of the installation is more important in a 20-speaker system than in a conventional system. Poor vibration insulation of doors will turn expensive speakers into a source of rattling and resonances.
System setup and calibration
After physical installation, the most difficult stage begins - configuration. With 20 speakers, manually setting the balance is almost impossible. A measuring microphone and specialized software are used (for example, REW or software from the processor manufacturer). The setup process takes from several days to weeks.
The first step is to equalize the volume levels (Gain) for all groups of speakers. Then the cutoff frequencies of the filters are adjusted. It is important to avoid overlap of frequencies where it is not planned, so as not to get boosts and dips in the frequency response (amplitude-frequency response). Phase correction is carried out for each pair of speakers.
⚠️ Attention: Don't turn up the volume on your amps in hopes of getting more bass. This will lead to rapid overheating and burning of the coils. The Gain setting should be done with an oscilloscope or multimeter using a voltage corresponding to the input power of the head unit.
The final tuning is carried out “by ear” using well-known tracks of various genres. The vocals, bass line, and the presence of whistles or hisses are checked. The system should sound holistic, creating the effect of the presence of musicians in the cabin, and not just make loud noise from all sides.
Frequently asked questions (FAQ)
How much does it cost to build a 20 speaker system?
The cost varies greatly. A budget option with Chinese components can cost 100-150 thousand rubles. A mid-level system with well-known brands (Hertz, Morel, Audison) and high-quality installation will cost 500-800 thousand rubles. Top-end SQ-systems for competitions easily exceed the 1.5-2 million rubles mark, not counting the cost of the car and work on remodeling the interior.
Is it necessary to change the battery on such a system?
Definitely yes. A standard acid battery (60-75 Ah) will be catastrophically small. You will need to install an additional battery (AGM or Gel) with a capacity of 100 Ah or more, and ideally, connect a buffer LiFePO4 battery, which is capable of delivering huge currents without voltage drop, which is critical for bass.
Is it possible to use a standard head (radio tape recorder)?
No, the standard head unit does not have the necessary linear outputs (usually there are a maximum of 3-6 pairs, but more are needed) and does not have the required DAC quality. The signal will be weak and noisy. An external DAC (digital-to-analog converter) or a specialized audio player with multi-channel output is required.
How do 20 speakers affect security?
If installed correctly, no way. However, heavy door podiums can interfere with the operation of the side airbags if they block the curtains. Also, massive structures in the trunk can become dangerous objects in an accident. Everything must be firmly secured, and access to emergency hatches and tools must be maintained.