We spent 29 hours trying out different car FM transmitters to come up with this list of the 5 best ones. Our checklist included range, sound quality, frequency spectrum, noise filters, saving station, RDS and transmitter ports. The Nulaxy Wireless In-Car Bluetooth FM Transmitter hits just the right criteria to take the first place. The Bluetooth capability on this transmitter ensures that it ticks the sound quality and range boxes. It has an impressive frequency spectrum of between 87.5 and 108.0 MHz. Extra features such as hands free calling, multiple ports and noise cancellation cement its first position.
FM Transmitter Buying Guide
What is an FM Transmitter?
An FM transmitter in the context of this article is a device that connects your car stereo to an external device such as a smartphone, MP3 player, SD card or CD player. The aftermarket device is wireless meaning that there are no cables that link the FM transmitter to your car stereo. Instead, the device typically connects to the cigarette lighter (for power) and sends FM signals to the stereo just like radio stations do.
A more detailed explanation is this; the FM transmitter receives audio output from the source it is connected to such as a smartphone or CD player. The device (transmitter) then converts this information into an analog format before converting it once more through a modulator into an FM signal. The car stereo then picks up the transmitter’s FM bandwidth just as it does with regular radio stations.
How to Choose the Best FM Transmitter
One of the first things that strike you when shopping for an FM transmitter for your car is the sheer range of options. There are a few pointers that you can use to help you get the best one. We used these same criteria in coming up with this list of the 5 best FM transmitters. The idea is to find a model that balances all of these considerations as the ones we have mentioned here do.
The range is certainly an important consideration since it directly affects the transmission quality. This shouldn’t be much of an issue with a car transmitter considering the confined space. Still, you want anywhere between 10 and 30 feet. If you would like to continue using the transmitter within a reasonable distance outside of your vehicle (via Bluetooth for example), 30 feet should be sufficient. All the same, more range means better quality signal so choose the higher number here just to be safe.
Unfortunately, you probably won’t be able to determine sound quality until you have plugged in and started using your transmitter. This practical problem is the reason we came up with this list so you don’t have to take the trail-and-error route. The devices listed here offered satisfactory sound quality.
One of the factors that affect sound quality is the distance between your car’s antenna and the FM transmitter. In an ideal situation, you would have your transmitter in the front seat if the antenna is in the front of the car and vice versa. Bluetooth offers the best sound quality so choose a transmitter that supports this feature if you are very particular about crystal clear sound.
FM transmitters work on free FM frequency (ones not taken by radio stations). This isn’t a problem in the sparsely populated area but if you live in a metropolitan, many of the FM frequency are likely already taken. A large frequency spectrum means that there are more options for your transmitter to pick a free frequency. You want a transmitter that works between 88.1 and 107.9 just to be on the safe side.
One of the differences you may notice while listening through your transmitter and listening to your regular radio is the background noise that is more pronounced on the transmitter. This issue doesn’t have to be the case if you choose a model with a noise filter function. We did our best to find you devices that filter out the noise and perform as close to the regular radio as you can hope. Some transmitters are also compatible with after-market noise filters.
The station saving feature is useful if you commute out of your range regularly. A common scenario is you have an open frequency that your transmitter works on when you are within the city. Once you leave the area, the same frequency is taken by a radio station forcing your transmitter to find another open frequency.
It can be a little frustrating searching for a new frequency every time you leave your range and reset back to the original once you get back. A transmitter that saves your open frequencies makes it easy for you to toggle to and from while traveling. This feature is more for your convenience than anything else.
Radio Data System (RDS)
Radio Data System (RDS) is simply the information you see on your stereo screen about what station you are listening to, which track on your CD and so on. Again, this is more of a convenience feature as it would be nice to know what you are listening to. The screen doesn’t have to be complicated as long as you can tell what you are listening to at any one time.
Finally, transmitter ports determine the range of devices you can use with your transmitter. If you are only interested in playing music from your CD player, a basic transmitter with an AUX jack port should suffice. We, however, advocate for as many ports as you can get including AUX jack and USB. Additional options such as Bluetooth and MicroSD card offers ultimate choice so there isn’t a device you couldn’t pair the transmitter with.
These are our top 5 picks for the best FM transmitters on the market. We concentrated on car transmitters although there is an option for home, work site or office. We used the criteria explained in the Buyer’s Guide and tried to be as objective as possible.
Note that any of these models could easily take the top position. The take-away here really is these are the options you should be looking at if you don’t want to go through the trouble of potentially testing tens of devices to find the right one.