How to choose a car amplifier

Any car audio enthusiast will confirm: if you want to achieve the maximum quality sound out of your system, an amplifier will become your lifesaver. Amplifiers have been evolving on the market for many years. That is why the most demanding customer can find a product to satisfy even specific needs. If you are new to this industry, the choice of a professional and effective car amplifier might be considered mission impossible. However, everything is not as hard as it may seem from the first or even the third glance.

For pros and entry-level users, any advice will be important. Our aim is to help you find perfect-match equipment, regardless of your budget and audio system specifications. In this article, you will get to know how to choose a car amplifier easily and without any headaches.

Stay tuned, and you will find out how to make the best money investment in your life!

Editor’s Choice

If you are new to our website, we would like to highlight the other works at our end. They will be helpful for your decision-making.

As you can see, the front-runners of our choice are the products by famous brands. And that is for a reason. It does not mean we have not investigated the equipment of non-so-well-known companies. However, the test of time has proven the reliability and longevity of the amplifiers which we believe to be the best in the industry. To trust a remarkable brand means to cooperate with a trustworthy company. In case if there are any problems with their device, they will not ignore you and help resolve the issue in the fastest and the most suitable way possible.

These articles provide a deeper and more specialized insight on the amplifier’s purpose and spheres of its use. Following those links, you will find the detailed descriptions of the best amplifiers. They will also show you how to choose the right amplifier for car speakers and much more.

Buyer’s Guide

In this section, we would like to give you some tips on how to choose a good car amplifier. Luckily or unluckily, it is not enough just to name the best car amplifier. It will be not suitable for all the range of possible cases. That is why continue reading our article and find out what to pay attention to when selecting such advanced equipment. Ready, steady, go!

How to select the right number of channels

Overall, there are different amplifiers’ configurations taking into account the number of their channels. Even though each of them could become a great suit for your car audio system, a particular situation distinguishes the peculiarities.

For instance, if you wish to choose an amplifier for your subwoofers, you would better go for monoblocks (in simple words, one or single channel amplifier). Their circuitry is designed in such a way to support not just a full range of frequencies. It also allows controlling bass production due to numerous filters.

When it comes to 2 channel models, their configurations opportunities allow customers to connect both speakers and subwoofers. The same concerns multichannel amplifiers overall.

The crucial part of your decision-making process is actually the number of elements in your car audio system. If you have a set of speakers and a sub, then you should go for a 4 channel device.

How to choose the proper wires for an amplifier

The choice of a perfect amplifier will not bring you satisfaction and incredible sound performance, unless all elements of the system are installed correctly. For instance, you can boast of the loudest and the biggest subwoofers accompanied by an amplifier of a great power, but if you use 18 gauge zip cord to connect them, it would be better for you not to check the result: the sound will be awful, when not worse.

What wires does car audio system need? It depends on several factors. Let us start with the necessary background information. In general, ground and power cables are used for transferring power from the car’s battery through the entire system, therefore for powering each of its elements. One of the most important and influential parameters here is the wire’s thickness. AWG is a number of its identification. The rule of thumb is as follows: the lower the gauge number is, the thicker the wire turns out to be. In addition, thick wire distinguishes with their ability to provide larger current flow, as well as less resistance.

To tell the truth, it is not that complicated to determine which gauge cables are appropriate. In order for your amplifier to operate correctly, it needs wiring large enough to accommodate its demand for electrical current. Compare that to drinking a milkshake. Certainly, you want to enjoy the beverage. For that, you take a thick straw to get the enough amount of the product. You will not prefer this tool to a thin straw. With the help of the letter, you will spend lots of time on drinking the shake and feel exhausted soon. Pretty the same concerns amplifiers as well.

Overall, the choice of the proper wire gauge depends on two things. First of all, you have to know the wiring run. Secondly, it is a must to find out the total current consumption of your car audio system.

Figuring out the length of wire you need is the easy part. In simple words, it is the distance from your battery to the amplifier’s location. Remember: measure twice, cut once. You can do that just with the help of a piece of string. When you get the length, do not forget to add extra three or four feet. Only then you may cut. Why is it needed to add some extra length? In case if you have made a mistake during the process, you will be thankful you cut more than necessary.

What should you do to select the proper wire gauge size? First of all, you have to determine the current draw of your amplifier. For that, it is necessary to calculate the total power of the system. To start, use this simple formula: multiply the number of channels by the number of RMS power per channel. After that, you divide the total RMS wattage by 12.8 watts. And voila — you get the current draw in amperes at 100% efficiency.

You might be interested why we use this number in calculations. In average, charging system will supply 13.2-13.8 V. When you supply a larger voltage, your current consumption will decrease and hence using a 12.8 V leaves some additional margin.

Unfortunately, that is not the final result. Please, note it is impossible to reach the complete level of efficiency. Depending on the amplifier typology, it will be necessary to use an efficiency coefficient and divide by it. For instance, class AB amplifiers are usually from 58% to 86% efficient, while class D devices are usually about 69% to 80% efficient. All the things considered, if your system can boast of two and more amplifiers, then you should perform the same calculations for each device separately. To get a final score, just add figures of each amplifier you have together.

Let us be more specific. For instance, if the result of calculations is 35-50 amperes, and the necessary length of the wire is up to four feet, then you will need 10 gauge wire. If the length of wire should be longer but with the same first parameter, then you will need less gauge wire. To get more details about each case possible, follow the link: https://www.qualitymobilevideo.com/power-ground-wiring-gauge.

For speakers with relatively short runs, 16 gauge is usually a solid sized wire. In turn, 12 gauge is more suitable for longer runs and for majority of subwoofers.

One of the most common problems with installs is a lack of current delivery. This issue is caused by either a weak ground or insufficient wire gauge, given the cable length or amp power consumption. If your wire gauge is not sized properly, then your amplifier will be starved for power. Obviously, it will result in poor performance. In turn, low voltage and low current at your amplifier will end up with clipping. To note, a byproduct of the latter is heat. All of this is potentially damaging both amplifiers and speakers. To avoid such safety hazard, we highly recommend you to pay attention to the proper installation. No matter how great the equipment is, it will be nothing when wired incorrectly.

How different modes influence the amplifier’s performance

Overall, there are three types of modes: stereo, parallel, and bridge (we will discuss this question on the base of two-channel amplifiers). Let us start with the most common mode. In a stereo mode, two channels are fully independent. That means each of them has its own level control and processing (by the latter we describe things like high and low pass filters). Therefore, the settings on channel one do not affect the settings on channel two and vice versa. Besides, this mode is probably the most versatile. It allows having two mono power amplifiers that you can deploy in whatever way you want. In turn, that makes two channel amplifiers working in this mode a great choice not for speakers only but for subwoofers as well. This setup gives you interesting options for playing with impedance: typically front-of-house full range speakers will be 8 ohms, professional cabinets are also usually 8 ohms (with the exception of large DJ type door woofer cabinets which are 4 ohms). So, if you combine two of those, you will have combined impedance of 4 ohms. This obviously raises the power output of the channel. Moreover, you can deploy one of its channels for your mains or front-of-house and the other channel to run stage monitors.

The difference between stereo and parallel is that two amplifier channels are connected internally: a signal to either channel feeds both channels. Things like high-pass filter limiters are still set independently. This mode is probably the least glamorous of the three. It is used in larger systems where want to avoid having to run jumpers between multiple amplifier channels. For instance, you can use this mode to run a large PA system where you have a combination of long-throw and short-throw speakers. In this case, you would send a full range signal to the amp, and then it would be split internally. This process is done within the amplifier, and no additional wiring is required.

Finally, the most mysterious and exciting of the modes to many people is bridge or bridge mono mode. In this case, what you are doing is you are using the two amplifier channels effectively as one large amplifier. In order to understand this, you have to realize what the amplifier is actually doing to the loudspeaker. Under normal circumstances, when you present a positive voltage to the input of an amplifier, the amplifier channel generates an electro-motive force that moves the loudspeaker cone forwards. When you present a negative voltage to the input of an amplifier, it moves the owner backwards. As a result of bridge mode, you get double the output voltage because you are using two channels instead of one. For instance, an amplifier produces 300 watts per channel into 8 ohms. When you bridge this device, you get 1100 watts power so that you can drive thousands of watts into a single loudspeaker. However, you should be careful using this mode. Do not forget that you double the normal minimum impedance in this process. So, if an amplifier could normally run 2 ohms per channel, you would be able only to run an amplifier into a 4 ohm minimum load in a bridge mode. Of course, the exact minimum load will depend on your amplifier. That is why consult the specification sheet.

How to perform series and parallel wiring using your amplifier

We would like to puzzle out this issue using the examples. First of all, let us consider the series wiring. If you wire up two 8 ohm speakers, this should give you a 16 ohm load. To start with, put a single wire from the negative to the positive terminal of another speaker. Your second connection is going to be the harness that has the jack on the end of it. You are basically just going to hook the negative wire up to the negative terminal, and to do the same on another speaker but with positive configurations. The connection is ready within a couple of simple steps.

By series wiring, you actually double the load. In this perspective, you achieve a 4 ohm load when connecting two 4 ohm speakers, a 32 ohm load with two 16 ohm speaker, etc.

To start parallel wiring of your speakers, use a twisted pair of wires to connect your positive and negative terminals on each speaker to each other. Once you have this connected, you just need to run the other wiring harness (twisted pair also) from the mono jack to positive and negative terminals respectively.

Unlike the series wiring, this method reduces the load. Therefore, with two 8 ohm speakers, you get a 4 ohm load. In case if you have two 16 ohm speakers, you will have an 8 ohm load after their parallel connection.

All in all, parallel and series wiring allows customers to enhance the amplifier’s capabilities, along with the productivity of subwoofers and speakers. In this perspective, you can either enlarge the output power you receive or reduce the load on your system and get more combination opportunities.

WARNING: Any time you are dealing with internal amp components, make sure your amp is both powered off and unplugged from the wall.

FAQ

1. Why is impedance important?

In simple words, this parameter allows to match such different elements as amplifies and speakers or subwoofers together without any risk of damage. The rule of thumb tells the figures of different devices should be equal. This will allow customers to achieve the outstanding sound performance even if the power of the system is relatively low.

2. Is low-budget equipment much worse than up-market devices?

To tell the truth, even though the technologies are changing rapidly, the standards are kept being approximately the same. When it comes to expensive solutions, their manufacturers often sacrifice the general quality to increase the number of features. So far, sometimes simple models are even better than advanced since they provide customers with solid functionality. Of course, before purchasing any amplifier, check the list of its specifications and match them to the needs of your system.

Conclusion

All in all, we have presented you basic recommendations on how to choose an amplifier for car speakers and subwoofers. In simple words, not to be overwhelmed with the process, just spend some time on investigating the issue. Do not hurry. In this case, it would be better to take some time off and make a thorough comparative analysis.

If you want to get an amplifier to boast of, go for one of our recommendations. We assure you that any of the items we offer customers is worth consideration. Since we pay attention to lots of details while selecting the equipment, each of the products is multifunctional and beneficial.

We hope that amplifiers will not turn out an epic failure for you. This challenge is definitely worth passing. Enjoy your perfect amplifier for years!