Anything with Bluetooth in it is bound to be more convenient and car amplifiers are no exception. They allow you to stream music directly via a Bluetooth-enabled device rather than connecting to your stereo. Hence, they allow you to stream wirelessly even if you don’t have a stereo or a head unit that’s compatible with Bluetooth.
Recently, a friend asked me what I thought was the best Bluetooth car amplifier to get currently. I had to admit that I hadn’t done my research this year. But that needed to change! So I rounded up 15 highly-recommended Bluetooth amplifier models and began my usual round of testing. You can read my review on my short-listed top five!
A Simple Guide to Buying Amplifiers
Before you buy an amplifier, you need to make sure that it’s well-suited for your needs and also that it’s compatible with your existing car audio set up. Hence, there are a few factors to consider before you make a purchase.
In this guide, I’m going to be breaking down the most important technical specs you should be looking at. These include class, power output, impedance, speaker sensitivity, and frequency response. If you’re confused by these terms, there’s nothing to worry about. I’ll be explaining what they are and why they’re important.
Most amplifiers belong to one of four main classes, which are A, B, A/B and D. The main difference between them lies in how efficient their circuits are. In this context, efficiency indicates how much Alternating Current (AC) an amplifier is able to output while using up the least amount of Direct Current (DC). Here’s a simple overview of the differences in efficiency among different amplifier classes:
Class A amplifiers are the least efficient of all. This is because they contain simple circuits that cause the unit to conduct 100% of the time. As you might expect, not all of this electricity will be used by your speakers, leading to a lot of wastage. Hence, their efficiency is around 30%. This continuous conduction leads to a lot of heat being generated as well, so you could cause a Class A amplifier to overheat if you use it for prolonged periods of time.
The biggest benefit of having a Class A amplifier is that they offer the best signal purity.
Class B circuits are designed in such a way that they only conduct electricity about half the time. This means less electricity wastage and thereby the efficiency is much higher (70%). The biggest drawback of Class B amplifiers is that they produce some signal distortion.
Class A/B amplifiers are a hybrid of Class A and Class B, combining the circuits of both. Hence, you get the signal purity of Class A but with the power efficiency of Class B. The Class B chain contains biasing diodes which are designed to help get rid of distortion that you typically get with those kinds of circuits.
Class D amplifiers are the most efficient (90 – 95%) simply because when they’re off, they’re genuinely off. This means that when you flip the off switch, the output transistors do not retain any electricity at all. Hence, there is none remaining to be converted to heat energy.
Amplifiers increase the volume of speakers and subwoofers by directing more power into them. Hence, if you want to be able to blast your music regularly, you’d need quite a powerful amplifier. However (and here’s the important part) your speakers need to be able to handle the amount of power that is outputted by the amplifier. If it exceeds their threshold for power-handling, then they can overheat and their internals may get fried.
Power-handling in speakers is measured by two specifications: RMS and Peak Power. The former tells how much power (in watts) a speaker can handle safely on a continuous basis while the latter sets the absolute maximum threshold for what it can handle.
Likewise, amplifiers also have RMS and Peak Power specifications but these refer to power output instead of handling. Typically, product information sections will tell you what the RMS is per channel. You need to make sure that your speaker’s RMS is equal to or greater than this value because otherwise, you’ll risk causing damage to it.
Do your speakers need a ton of power to get really loud? That’s exactly what a speaker’s sensitivity rating will tell you. Speaker Sensitivity specifies how loud a speaker will get (in decibels) when you supply just one watt of power to it. For instance, if a speaker’s sensitivity is 85 dB then that would tell you that it gets moderately loud when driven by one watt. For each additional watt you supply, you can add 3dB to the volume.
The higher the sensitivity, the lesser the amount of power a speaker needs to get to a certain volume.
Impedance measures the amount of internal resistance (in ohms) that your amplifier possesses. The greater the impedance, the harder the amplifier has to work to output a certain amount of current. Hence, a low impedance is less stressful on an amplifier however it isn’t always ideal. If an amplifier’s impedance is too low, then it can supply more current than a speaker can handle.
Most amplifiers will have an impedance of 4 ohms but will let you switch to a 2-ohm setting if you require more power. Most product information sections will list the RMS of the amplifier at each ohm setting which is rather convenient.
Some amplifiers are designed to work with both regular speakers and subwoofers while some can only be paired with the latter. An amplifier’s frequency response will tell you what type it is. It is essentially the range of frequency that an amplifier can handle. A full-range amplifier will be able to handle all the signals in the human audible range (20 Hz to 20,000 Hz) while a subwoofer unit will be restricted to the bass spectrum (20 Hz to 250 Hz).
Hence, make sure to always pay attention to the frequency response, so that you don’t accidentally buy the wrong amplifier for your set up!
The Number Of Channels
The number of channels you need in your amplifier depends on how many speakers you have in your current set up and whether you might make any further additions in the future. 5-channel amplifiers are extremely versatile. They have 4 regular channels and a dedicated subwoofer output. Hence, you can connect up to four speakers and a subwoofer as well.
The Ability To Bridge
Bridging an amplifier basically involves consolidating the power output of multiple channels into one. This is typically done in order to make the amplifier more compatible with a subwoofer since they need way more power than regular speakers. For instance, you can bridge a 4-channel amplifier into a 2-channel mode which allows you to connect to a pair of subs.
Bluetooth Car Amplifier Reviews
Now that you’re well aware of what you need to consider before buying an amplifier, let’s take a look at my top five Bluetooth car amplifiers for this year, starting with the:
- This class D amplifier Supports USB coaxial analog Bluetooth and two...
- With amplifier output port, 3.5mm headphone jack and subwoofer...
- Customized BT4.2 Bluetooth module, Supports apt-X, easily connect with...
- The Bluetooth amplifier uses tas5508c+tas5342a from TI as amplifier...
- What you get: SMSL AD18 amplifier, 24V power supply us Plug, Micro USB...
The SMSL AD18 Class D amplifier has a frequency response ranging from 20 Hz to 250 Hz, which means that it was designed to only work with subwoofers
80 Watts RMS
Each of the two channels on the SMSL AD18 has an RMS rating of 80 watts. If you’re not the type of person who likes cranking up the subs to ear-splitting volumes on a regular basis, then this power output should be enough. Otherwise, you may need to consider another option.
Not many amplifiers feature a coloured display so this was quite nice to see. This 1.44-inch screen allowed me to easily keep an eye on the output level while I was driving, preventing me from having to lean in and take my eyes off the road for longer.
One of my favourite things about Bluetooth 4.2 is its support of Apt X. Apt X is a high-quality audio file transfer method. Bluetooth has restricted bandwidth so it has to compress larger audio files before transferring them. Apt X manages to reduce the amount of compression that occurs normally, resulting in the music better retaining all of its details and nuances.
Bluetooth isn’t the only way you can play your music through the SMSL AD18. It also features a micro USB input and a headphone jack as well. I found the former quite useful since I’ve got most of my ‘on-the-road’ playlists saved on a USB stick instead of my phone. The headphone jack is occasionally useful as well, particularly when I want to listen to a podcast or a meditative tape in private. If you plan on using the headphone jack make sure you’ve got the amp mounted in an easy-to-reach spot!
Compact and Lightweight
The SMSL AD18 weighs only about 3.5 pounds so it’s hardly a hassle to install. Plus with a width of 6.8 inches, you’ll have multiple location options when setting it up.
- Coloured display
- Compact and lightweight
- Bluetooth 4.2 with Apt X
- Only works with subwoofers
- May not be enough power for some
- New Kenwood 4 channel Bluetooth marine atv motorcycle amplifier...
- 45 watts x 4 at 4 ohms
- Peak power: 400 watts
Wide Frequency Response
The KAC-M1824BT 4-channel Bluetooth amplifier by Kenwood is able to handle the entire audible range of frequencies from sub-bass to upper-treble. Hence it is designed to work with both regular speakers and subwoofers.
45 Watts RMS
45 Watts might not sound like such a big deal but it’s actually quite adequate, especially if you’ve got a speaker that’s already very sensitive (90 dB or more). If you need a bit more power to connect a pair of subs, you can bridge the amplifier into a 2-channel mode, which then bumps up the RMS in each channel to 90 watts.
Bluetooth with Apt X
Just like the SMSL AD18, this Kenwood amplifier comes with Apt X-supported Bluetooth. If you’re an audiophile like me, you’ll greatly appreciate how well it helps to retain the original quality of your music.
The KAC-M1824BT also comes with a Bluetooth-enabled controller which you can use to tweak the volume of the amplifier and change tracks. I actually found myself using it a lot while I was driving.
Conformal-Coated Circuit Board
Conformal coating is a sort of polysynthetic film that is resistant to both dust and water. This is good news for anyone who goes off-roading. Particularly, when engaging in activities like crossing a river.
- Compatible with both speakers and subwoofers
- 45 Watts RMS
- Can be bridged to connect subwoofers
- Bluetooth with Apt X
- Water and dust-resistant
- With a width of almost 15 inches, this unit is a bit large
- 200 watts RMS x 2 bridged at 4 ohms + 350 watts RMS at 2 ohms
- Wired remote unit has controls for Bluetooth streaming, hands-free...
- Preamp and speaker-level inputs
- Max Power 2300W Peak
The 5-channel Infinity K5 handles the full audible range of frequencies. It consists of 4 channels that you can connect your speakers to as well as a dedicated subwoofer output with a higher RMS.
At the default impedance of 4 ohms, each of the Infinity K5’s 4 speaker channels has an RMS rating of 75 Watts which is more than enough for blasting your music out loud on the regular. The dedicated subwoofer output, on the other hand, has an RMS of 200 watts, allowing you to connect to a high-powered sub.
If you need even more power, you can switch the impedance down to 2 ohms, which bumps up the RMS to 100 watts and 350 watts on the speaker and subwoofer channels respectively.
If you’ve got a pair of really high-powered speakers plus a subwoofer, you can try bridging the amplifier into its 3-channel mode (2 speakers and one sub). The bridged speaker channels will have an RMS of 200 watts while the subwoofer channel will output a maximum of 350 watts.
Variable High And Low-Pass Filters
High and low-pass filters are EQ tools that you can use to shape your tone. They set cut-off frequencies so that signals that are either higher or lower in pitch are removed from the path. The filters found in the Infinity K5 are variable, which means you can decide what the cut-off frequency is within a given range.
The high-pass filter blocks all frequencies below the cut-off and is only found in the speaker channels and works in the range of 32 Hz to 320 Hz. What I like to do is set the cut-off really low so that I can prevent any distortion in the extreme low-end.
The low-pass filter, on the other hand, is only available for the subwoofer channel. It has the exact same range but it cuts off frequencies higher than the set threshold. Hence, you can use it to set the cut-off quite high and get rid of distortion in the upper-bass region if you notice any.
Dynamic Bass Optimizer And Subsonic Filter
These controls can be used to enhance the bass response of your subwoofer. The Bass Optimizer is an adjustable bass boost that lets you increase the volume of all signals at 45 Hz by up to 12 dB. The subsonic filter is essentially a high pass filter that’s specifically focused on the sub-bass frequencies. The K5’s subsonic filter lets you set the cut off anywhere between 10 Hz to 80 Hz.
The wired remote allows for hands-free tweaking of the amplifier, including adjusting volume and Bluetooth options. It also lets you switch to ‘Party-Mode’ which is a feature that allows up to three sources of Bluetooth streaming. If you carpool to work, then ‘Party-Mode’ can be quite fun.
- Full-range amplifier
- High RMS for both the speaker and subwoofer channels
- Variable high and low-pass filters
- Bass optimizing controls
- Wired remote
- With a width of 13 inches and a depth of almost 7, this amplifier isn’t exactly compact.
- 100 Watts RMS x 2 @ 4 ohms
- 120 Watts RMS x 2 @ 2 ohms
- Total Peak Power: 700 Watts
- Clari-fiTM Technology
- Bluetooth Streaming
The JBL GTR-102 2-channel amplifier is able to handle all audible frequencies from 20 Hz to 20,000 Hz. Hence it can be used for both speakers and subs alike.
Tons of Power
When its impedance is set to 4 ohms, the GTR-102’s 2 channels will be able to output 100 watts on a continuous basis. Switch it down to 2 ohms and the RMS climbs to 120 watts. I can’t imagine too many scenarios where you’d need this much power with regular speakers.
The amplifier can also be bridged into a one-channel mode with an RMS of 240 watts. This is useful if you only need to connect a high-powered subwoofer to the unit.
Adjustable High- and Low- Power filter
The variable high and low-pass filters in the GTR-102 allow you to set the cut off anywhere between 32 Hz to 320 Hz. Hence if you notice any white noise or distortion in the bass, you can use these filters to clean that up.
Wired Remote Unit
The remote unit included with the JBL GTR-102 is very similar to the one you get with the Infinity K5. It allows you to control Bluetooth streaming as well as switch to Party Mode.
At almost 9 inches wide, this amplifier is a relatively compact unit.
- Full-range amplifier
- High power output even at the default impedance setting
- Compatible with high-powered subs
- Variable high and low-pass filters
- Included remote control
- I’m having trouble thinking of any
- Class-d amplification technology for high power
- DSP with 4.1-Channel time alignment
- Customized sound with app control
- Low and high Pass filters for accurate sound
- Heavy duty aluminum case
Being a 6-channel Class D amplifier, the Sony XM-GS6DSP can accommodate both speakers and subwoofers.
The channels are configured as follows: Channels 1 and 2 can be paired with tweeters and mid-range drivers, Channels 3 and 4 with mid-range drivers or woofers and 5 and 6 can either run a pair of woofers or be bridged to run a subwoofer.
At 4 ohms, the Sony XM-GS6DSP outputs 45 watts RMS via its 4 tweeter and mid-range channels plus 90 watts RMS through its woofer channels. When switched to 2 ohms, the latter outputs 175 watts RMS. If you do need more power to connect to a subwoofer, the woofer channels can be bridged at 2 ohms, bringing up the RMS to 600 W.
Custom Tuning Via App
The XM-GS6DSP is compatible with Sony’s Music Center app which gives you all sorts of tone-shaping tools such as a 10-band EQ, speaker level controls and a fader. Simply connect your phone via Bluetooth and you can tweak on the fly.
- Full-range amplifier
- Dedicated outputs that power tweeters, mid-range drivers, woofers, and subwoofers.
- The custom app gives tone-shaping controls
- At 11 and a half inches in width, it’s not the most compact amplifier out there.
Best Bluetooth Car Amplifier
Choosing my overall favourite Bluetooth amplifier was easier said than done, considering they were all solid choices. I then asked myself which amplifier I would stick with for at least a couple of years and the answer became quite apparent: the Infinity K5.
Here are my reasons:
- First of all, five channels seem like the perfect amount considering I’ve got 3 speakers and a subwoofer in my own setup. The amount of power it outputs was perfectly adequate even at the default impedance setting.
- The high and low-pass filters and the bass optimization controls came in handy on occasion when I was listening to my EDM playlists. They helped me clean up any distortion in the low-end and give it more ‘attack’.
- Lastly the wired remote was very useful because it helped me tweak the amp on the fly even while I was driving.
Frequently Asked Questions
Can I Add Bluetooth To My Amplifier?
This can be done by using a good Bluetooth adapter. Simply connect the adapter to your amp (make sure it’s also plugged into an AC outlet) and then pair your phone to it.
Is Bluetooth High-Quality Audio?
More recent Bluetooth versions such as 4.2 and 5.0 are better at transferring audio with minimum compression. Look for Apt X-supported Bluetooth amplifiers as well because it reduces compression even further.
Is Bluetooth Audio Better Than Aux?
Bluetooth tends to compress the sound more than aux resulting in relatively decreased audio quality. However, the truth is that most people will be unable to tell the difference between Bluetooth and Aux audio.
Do Amplifiers Improve Sound Quality?
Amplifiers, in general, are used to make your set up louder rather than shape its tone. That being said, amps like the Infinity K5 or the JBL GTR-102 do come with tone-shaping tools like high- and low-pass filters.
How Do I Choose An Amp For My Subs?
Amps designed specifically for subs will have a frequency response ranging from 20 Hz to about 250 Hz. However, you do get 5-channel full-range amplifiers that have dedicated subwoofer outputs as well. You also need to consider the power output and whether it’s enough to power your subs.
The products featured on this page were last updated on 2020-02-22 at 18:35 /. Affiliate links / Images from Amazon Product Advertising API.