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Give your speakers what they deserve: car amplifiers for sale on HiFi Tower

For a high-quality listening experience while you're in your car, you can find an endless range of equipment, such as car subwoofers and speakers which are specifically designed to deliver a clear and powerful sound in passenger compartments. To achieve an optimal result, however, you may consider adding a proper car amplifier, and before you buy one it's essential to design the system you intend to install, opting for a model whose features are matching the specifications of your car stereo and the number and quality of speakers you use.

All car amplifiers for sale on HiFi Tower are designed to meet the most diverse needs, from 2-channel models, to push a subwoofer and a pair of speakers, to 6-channel models to cater for the requirements of more advanced in-car entertainment systems. Thanks to their durable materials, pleasant aesthetics and above all, capable of handling maximum power peaks without any risk of damaging your car speakers, the car amplifiers for sale on HiFi Tower are your faithful companion, working at the rear and always guaranteeing you a warm, powerful and clean sound when you are on the move.

When your car stereo is not enough: why buy a dedicated car amplifier?

In any audio system, the purpose of an amplifier is increasing the power of the audio signal generated by the source. With car sound systems it’s no different, and the car radios we generally use in our vehicles already include an internal amplifier, to connect directly to the car speakers that are part of the standard setup.

Car speakers, however, perform much better when dedicated amplifiers power them. Not to mention the fact that a passive subwoofer will anyway require a dedicated amp, as bass sound waves need a lot of power that standard car stereos cannot generate. For all these reasons, if you plan to install a high-quality sound system in your car, using a car amp is imperative to achieve the same degree of depth, realism and dynamics of a live music experience.

Single and multi-channel car amplifiers

The first aspect to consider when purchasing a car amplifier is the number of speakers that you intend to connect; this is the main element on which, eventually, your choice will depend. By channel, we mean an independent audio path used to emit a signal from the amplifier.

There are several possible configurations, suitable for different needs. Single-channel amplifiers are normally used only to connect a subwoofer. They don’t offer any kind of flexibility. Still, they are more than enough if the only improvement you want to make to your system is the addition of a speaker dedicated exclusively to bass reproduction. There are several options available if you opt for an amplifier with multiple channels. You can find models with two channels, while others can offer up to eight. The greater the number of channels available, the wider the number of possible configurations for your amplifier. Although you can generally connect every single channel to a speaker, other connection modes ensure greater freedom of customisation, as we will see in the following section.

The answer to this question depends essentially on your listening preferences, and here we provide only some general information to guide you in the choice:

  • 4 channel ampr: if you need more power for your front and rear speakers, a 4-channel amplifier is the recommended choice, even when you need to power the typical two front speakers plus a subwoofer. This is particularly convenient when you build your car sound system piece by piece: a 4-channel amplifier allows you to operate the front speakers and subwoofer, and the built-in car stereo amplifier caters for the power needs of your rear speakers. At a later stage, if you decide to upgrade your in-car entertainment system adding a dedicated subwoofer amp, you could take advantage of the two remaining channels that were not in use before, to power your rear car speakers.

  • Mono amplifier (1-channel): if you simply need to add a subwoofer to your existing system, you can consider buying a mono amplifier. Ideally, you should opt for one with bass equalisation system and a low-pass filter, to help reproduce bass notes loudly and clearly. 1-channel mono amplifiers operate at a broader range of impedances and feature tone controls and filters specifically designed to improve bass reproduction.

  • 5 channel amp: are you planning to power a complete system with four speakers and a subwoofer? As well as conveniently centralising all the controls in one device, using a 5-channel car amplifier means you won't have to use two separate sets of speaker and subwoofer power cables. Most 5-channel amplifiers can power and control a fully active 2-way front module and subwoofer system on their own. Two channels are used to drive the tweeters, two channels ower the midranges, and you still can use the last remaining one for the subwoofer.

  • 2 channel amp: most car sound systems consist of just two speakers, and a 2-channel amplifier is the most efficient solution to drive them. A 2-channel amplifier can also be used to power a subwoofer when used in single-channel bridge mode. Many car stereo enthusiasts, however, choose a mono amplifier to control their subwoofers because they offer more capacity for low-frequency reproduction.

Main technical features to consider to find the best car amplifier

Power, expressed in RMS watts, is a crucial aspect to consider when choosing your car amplifier; as it indicates the continuous power that the speaker can withstand in the normal playback phase. As a rule of thumb, when you are upgrading your car sound system, it is best to opt for an amplifier with an RMS power between 75% and 150% of the power of the speakers you already use.

Peak power is another important parameter; differently from RMS power, peak power refers to the maximum power level to which the speaker can be subjected for a short time without any risk of damage. However, it is also important to evaluate other parameters, which help determine the actual sound quality that an amplifier is capable of delivering. These include:

  • signal/noise (S/R) ratio. The higher the S/R ratio, the better the sound quality will be

  • total harmonic distortion (T.H.D): it indicates the degree of 'fidelity' of the sound generated by the amplifier with respect to the input signal.

  • amplification class: this specification indicates how the internal transistors work and ranges from A to D. Without going too deep into technical aspects, class-A amplifiers have minimal distortion levels and maximum audio output, but also greater heat loss and therefore low energy efficiency, as they remain in operation even when the signal is not passing through. Conversely, class D amplifiers are more efficient, at the expense of accurate frequency reproduction, especially when high pitched. When it comes to auto amplifiers, the intermediate classes such as AB are the most common, combining the advantages of previous stages and providing good versatility in different music programs.

  • damping factor(DF): the higher it is, the better the amplifier will control the movement of the loudspeaker when reproducing low sounds: for this reason, it is crucial in subwoofer amplification

Why is impedance essential in a car amplifier?

In addition to power and number of channels available, there are also other important parameters to consider when determining compatibility between an amplifier and other components of a car sound system. One of the most decisive of all concerns impedance, on which not only the correct functioning but also the integrity may depend.

Ohms (Ω) measure impedance, a value that indicates the resistance that the amplifier exerts on the sound. The lower the impedance, the stronger the audio signal reaching the speakers will be. Although impedance may seem to be a secondary factor, it is instead a decisive element in determining the correct functioning of an audio system: if the amplifier is too powerful, the speakers risk being irreparably damaged. On the other hand, if the amplifier is not powerful enough, there is a risk of overheating and potentially burning out part of the entire system, also noting that different values in Ohm may correspond to different channels.

It is crucial to remember this risk, especially if you choose an inexpensive amplifier, as these often do not have a safety system that automatically deactivates them in case of danger. When choosing a car amplifier, therefore, it is vital to evaluate not only its power but also its impedance, making sure that it is compatible with the rest of the components you use for your system.

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