Four Ways to Play your MP3 through your Car Stereo
If you’re like many of us, you’ve invested a lot of time and money in creating a great collection of songs on your MP3 player, and you want to be able to enjoy them wherever you are. Sure it’s great to hear your music when you’re walking, riding a bike, or out jogging, but what about when you’re in your car? Listening to music while traveling seems to be a natural combination, but how can you listen to your songs using your car stereo? Here are some options:
AUX input on stereo itself
If you’re lucky enough to have a relatively new car, your stereo probably has an AUX input on its face. All you need to do is connect a 1/8″ (5mm) stereo cable from the headphone jack on your MP3 to the AUX input jack on your stereo. Select AUX as your input on the stereo itself and you’re in business. The cables only cost about $5 and are available almost anywhere electronics are sold.
The only downside to this set up is you need to be sure your MP3 is well charged and have your charger close by as your stereo won’t charge your MP3 while it’s playing.
Don’t have a new car with an AUX input? You’ve still got some options.
Cassette adapter
This is probably the most cost-effective option you can find. A cassette adapter looks like an old cassette tape except it has a small 1/8″ inch wire coming out of it that you plug into the headphone jack of your MP3 player. Simply insert the cassette adapter into your car’s cassette player and your digital music will be played through your stereo.
The obvious problem with this solution is that not many cars have cassette players in them any more.
Wireless transmitter (FM transmitter)
This tiny transmitter device plugs directly into the headphone output of your MP3 then transmits the music as FM radio waves that can be picked up by your car stereo. You set the transmitter to a particular FM frequency (station) that isn’t being used by a radio station then tune your stereo to the same station and you can listen to your songs through the stereo.
Unfortunately this option has a couple of issues associated with it. Both the transmitter and MP3 are being powered by the MP3 so it will quickly run out of battery power (although some newer transmitters do include a charger option that can actually charge both your MP3 and the transmitter.) Also if you’re travelling any distance, a radio station along your route could use the FM frequency you have selected, so you may need to adjust the tuning on your transmitter and radio.
Direct connection
A wired adapter that connects directly to your car stereo provides the best possible sound quality. Just as the name implies the adapter is wired right into your car stereo (usually on the back of the unit), and a 1/8″wire is run out front to a convenient location. You simply plug the wire into your MP3, and it plays directly through the stereo unit with the added advantages that you can often control your MP3 (volume, song selection) through your stereo and the adapters will often charge your MP3 while it plays.
The disadvantage is these wired adapters usually require professional installation.
If you need to find a user manual or get product support for your MP3 player or your car stereo system, visit the OwnerIQ Library.

11 Responses to “Four Ways to Play your MP3 through your Car Stereo”
As a Ford owner, the stereo has controls for CD changer that would be located in the trunk. There is a device that plugs in the CD Changer connections that has RCA spreaker inputs. A $5 cable that is RCA to 1/8″ plug is then run from the trunk to the cabin. Viola! Your MP3 device is connected to the via the earphone. The conversion device is fairly inexpensive and took me about 15 minutes to install with no tools required. It took longer to route the cable to a convenient spot in the cabin. Check e-bay and Amazon for the conversion devices. Good Luck!
By Bookman on Feb 24, 2009
My newest car stereo unit, a Dual, has a USB port built right into the front, so you can plug in your flash drive or your MP3 player if it has a USB connection or a USB cable. The sound quality is very good this way, also, the USB will provide power for your device, so no need to be concerned about the battery going dead in the middle of \Stairway to Heaven\ or \the 1812 Overture\!
By Mike on Mar 1, 2009
Very nice blog! This guide helped me tons
really appreciate it. thank you.
By Mp3 Player Music on Apr 11, 2009
Stick with wired, USB, or FM. Cassette is too finnicky and the sound is poor.
Personally I use a Blaupunct DAB / CD unit in the car, but never play CDs now. I’m lucky and have Aux and SD card slot. I just rip all my CDs to a network drive (PC would do most folk) and as all my music is in MP3 (plus some flac and DTS) copy to mem card OR an mp3 player as required. SD is great as I control it from the head unit, like a CD, but you get a lot of albums on a 3gB card.
Cassettes are dead; CDs too (for car use anyway; personally speaking). So look for USB slot; SD slot, and Roll on the digital revolution ! I Hope this helps.
By John on May 10, 2009
Please be Careful with the FM TRANSMITTERS> I bought an IRIVER FM Transmitter for my car, and because the 12V outlet is situated underneath my car stereo, the signal was powerful enough to fry the radio circuits of the Stereo. The CD and the cassette work just fine, but I can no longer receive any radio, FM or AM because of this. If you are going to use the FM transmitter, locate it as far from the stereo unit as possible. And GO big or go home. I thought I was getting a good deal on the IRIVER. I should have spent the extra to get a higher quality brand. Don’t get “burned” like I did.
Ken
By Ken on Jun 3, 2009
Roadmaster USA makes a really good car stereo fm transmitter. They even have one that will take a USB thumbdrive and play your files off of it.
By Troy on Jun 3, 2009
My car stereo has a USB port. I wonder if I can play the mp3´s stored in my cellphone connecting to the USB port from the headphone output on the cellphone, provided I find a cable or a connector (3.5mm male into USB).
I know there are easier way to listen to MP3´s, I just wonder if it can be done this way?
Any thoughts on this?
Gaby
By Gaby on Jun 16, 2009
i need an audio sound for my pc
By karekezi on Jun 21, 2009
Georges response regarding a 12vdc FM transmitter frying his radios receuiver is just assanine. FM transmitters fall under FCC guidelines for sale in the us and are limited to a maximum of .50 mIlliwatts of output, in comon terms that is .005 of 1 watt. That is nowhere near enough frequency modulated RF output to fry anything.
By george on Jun 21, 2009
I connected my mp3 player (sansa fuze 4gb) to my cars head unit by using the same method I use to get sound from my pc to the tv/stereo stand on the other side of my den at home. This is simply a headphone jack (“miniplug”) to RCA (Y) cable. This worked fine, and today I drove around a bit and enjoyed it. I’m sick of discs and this older jensen head unit doesn’t play very well (and the antenna is screwed up apparently bc reception is awful makng a fm transmitter for mp3 players nearly worthless for me) THAT WAS ALL FINE UNTIL…. I unplug and see my player display “refreshing media” as it does after you have added files. That was odd, I thought- then when I plugged in my headphones I heard snaps, crackles, pops, and a general low distortion that was very noticeable until the volume was over about 70%. I tried other headphones- same result. Scoured Sansa’s troubleshooting stuff online and haven’t found anything yet. I can use the player with the volume at 100%, then adjust with my headphone’s in-line volume control, at least. I walk my dog long distances every evening listening to the player and also plug it in to my stereo very often when the pc is being used for gaming or something. Point being…I use this player (and the 1gb sansa I had before it that finally died but I plan to ship off- I have tried all methods of de-bricking it online) ALL the time. Even if sending it to sansa would get it fixed I suppose it would be stupid to plug it into my car headunit’s aux input rca’s again… of course it would. I have tried every inventive search I can think of and still am not finding info that directly pertains to this occurence and residual problem.
If anyone had any real knowledge about what happened exactly (I’ve never been too handy with electronics aside from hooking them up- never knowing why something may have been “fried” a bit, etc) then please…please let me know something. Thank you. I love these Sansa players, especially for the price- but when you google troubleshooting you surely find a ton of war stories. With my older sansa I used to have to soft and “hard reset” it often, then tried holding two buttons down while plugging the usb in (the official instructions) and still had no luck, though others do. I don’t know if formatting it would fix this, and I don’t know atm if formatting leaves you needing to download anything from Sansa either. That’s what I’m about to look into. I hate to end up with NO tunes when I’m on my long walks rather than gritty, distorted tunes that aren’t noticeable really with the player turned completely up. It’s even making sounds like you would hear while fiddling around an electric guitar pickup when you skip to the next track right now… stuff like that.
Again…anything…please. I thank you.
- Simon
By josh on Jan 1, 2010
Josh, I hope you have had luck with your Sansa mp3 player problems. If not, take a look at a slightly higher investment/different make of player. I’ve used the iRiver T10 and also a few others, and it is usually an easy call to make that the lowest end of the spectrum, in whatever product you buy, the more you’ll find issues with durability. Car stereo and automotive use in general will really test the durability of the product that you are trying to use. Notice that most of the car units have a 90 day warranty, if that! Also, it is important to understand the type of signal that you’re putting into the unit. Some of the questions that I’ve read here have to do with users trying to put an analog signal into a digital port (Gaby back on June16, 2009).
In short, not all systems will give you the results that you want. See what works with other people and get a good understanding of what is going on.
By Mike on Feb 22, 2010