FM Transmittors. Do these work?

Discussion in 'iPhone Accessories' started by kdesign7, Sep 6, 2010.

  1. kdesign7 macrumors 6502a

    Feb 1, 2010
    earth, for now.
    Ok so - quick question. Im just doing some shopping around for an FM Transmittor for my iPhone 4.

    I found a few online with GREAT reviews, but it doesnt say on the package (for obv reason) if they work with the iPhone 4.

    Curious... In general form.. does these types of Transmittors work with the iPhone 4... I have a FEELING they will - but I'd like to get some input.




    - Basically Im wondering if most of the FM transmittors that connect via the 30-pin connector, if they will work... I know the other types that plug into the HeadPhone jack work, but Im very much curious about this style.

    Thanks for your help.. I appreciate your time!
  2. TheConfuzed1 macrumors 6502a

    Jun 4, 2003
    They work, but if you use one, you're essentially turning digital music analog.

    They have the potential for interference, and often get static like a radio station may when it has a weak signal.

    Nothing works like a direct connection.
  3. dunxxx macrumors regular

    Jul 15, 2010
    SF, CA
  4. kdesign7 thread starter macrumors 6502a

    Feb 1, 2010
    earth, for now.
    This is no different than a Sirius Satellite radio, correct?! I mean, it broadcasts to a Frequency... And Ive noticed it's NOT as clear as a CD Would be.. but it's -useable- for whatever I would use it for. I mean, I dont BLAST my tunes so I wouldnt be able to hear every lil static or wutever!

    Thanks so much for ur reply, I appreciate!
  5. kdesign7 thread starter macrumors 6502a

    Feb 1, 2010
    earth, for now.

    Sadly, I only have the factory stereo.. lol. Its not that great, but it'd still be nice to hear my tunes over the car speakrs! :) Thx mate!
  6. ChrisBrightwell macrumors 68020


    Apr 5, 2004
    Huntsville, AL
    What a completely useless statement. This ultimately happens when your music hits the speaker wire, if not before. Do you use one of those $3 RCA cables to connect your iPod/iPhone to your stereo? Analog!

    To the OP: What matters, really, is that cheap FM transmitters sound like sh-t by design. FM is garbage, really, and cheap FM transmitters are absolute trash. If you care anything about music, I'd strongly recommend spending your money on a more direct connection.
  7. Hemmo macrumors regular

    Aug 22, 2010
    I have fm transmittor from belkin and i newer use it.It keeps getting interference from radio stations (and powerlines?)
  8. -C- macrumors regular


    Jul 31, 2010
    If you live in a big city with crowded FM stations you will be frustrated. It's passable in other areas but like others have said it's lower quality than a direct connection. Maybe download the instructions first and see which frequencies the transmitter occupies to see if your area is free and clear of broadcasts around them.

    In my area, Los Angeles, they don't work very well. Stations bleed in too much while driving around.
  9. ericschmerick macrumors regular


    Dec 18, 2004
    That's a pretty strongly worded statement, and quite a bit more useless than the previous post. In fact your statement is worse because it's a misrepresentation of the issue, rather that a simple statement of fact (as was the previous post, to which you responded).

    Listening to music is and always will be an analog process. Your red-herring statement points that out clearly. Our ears are analog. However the process of getting from digital (bits) to analog (sound) is completely different between the originally cited case (Frequency modulation, transmission, and demodulation) and the case you're citing (direct transmission to a speaker, or amplifier). You could use the same argument to say that FM transmission is the same as plugging into the headphone jack and listening to your headphones - "they're both analog!"

    Frequency modulation (FM) involves taking the analog signal from your source, modulating it onto a higher frequency (in this case, something in the normal broadcast FM band) and into the frequency domain, amplifying the modulated signal, broadcasting it, receiving it, and demodulating back from the frequency to amplitude domain.

    FM as defined for broadcast allows a 30hz - 15,000hz frequency range for the source signal. You're throwing away anything outside of that range. There are significant sources of distortion inherent in the modulation / demodulation process. The signal-to-noise ratio is typically very poor compared with directly sending the analog signal to speakers (phones) or another, reasonably high-quality amp.

    The act of digital to analog conversion and then sending (over your hypothetical RCA cable) to an amplifier is quite simple. There is no modulation. There is no filtration of the signal to conform to limit the bandwidth. It's the original analog signal, sent directly to an amplifier, or better yet, speaker (headphones). Sure there are noise sources in the digital to analog conversion process, but they are tiny compared with the sources in the frequency modulation / transmission / demodulation case.

    In the end, though, even though you put forward a fallacious argument, you found your way to a reasonable conclusion. FM transmission isn't very good. It's way better to find a direct (analog, or better yet digital) transmission method.

    I've use three different FM transmitters. At best, the music sounded crappy (as one might expect, given the issues enumerated above), and under normal circumstances it was noisy and carried some (or a lot of) static. Further, if you live in a big city (like the bay area), there are very few FM frequencies that are unoccupied - and even the "out of band" frequencies carry some interference from broadcast stations.

    Final note, digital satellite radio is absolutely not the same as FM radio in terms of sound quality. Digital satellite radio is sending an analog modulated BIT STREAM (i.e. digital bit stream), just like digital cable / satellite TV. You either get a perfect CD-quality stream, nothing (loss of lock), or a some kind of stuttering signal (bit dropping). But you will not have static, and you should, under normal circumstances, get a signal that is equivalent to a one-step digital to analog conversion.
  10. Jumpman2033 macrumors regular

    Jun 27, 2010
    for those saying that Direct connection (assuming auxillary input) is the way to go, what is the easiest and cheapest way to install one? I have a 2005 Chevy Cobalt (basic model) with factory stereo. I don't want to put a lot of money into it because i don't plan on keeping it too much longer (maybe 2 years). Any info and/or ideas would be greatly appreciated.
  11. h1r0ll3r macrumors 68040


    Dec 28, 2009
    Direct connection is the best way to go although it can get a little pricey depending on the parts needed. I have an '06 Pathfinder and it would've cost me about $100-$150 to install the necessary parts in order to have my iPhone direct connect with my headunit. In my case, I needed to buy two cables and install them myself. One was the auxiliary cable to connect directly to my headunit and the second cable was to connect from the aux cable to my iPhone. After googleing the process, it seemed pretty straight forward however you would need to tear into your dash pretty deep in order to install the cables. If the price point is doable for you, I'd suggest you look at and see what cables are required for your car, then look around and see if you can find any cheaper ones. I hit ebay for the cables for mine however the price points weren't that much cheaper than retail unfortunately.

    And to the OP; every single FM transmitter I've bought/used sucked....big time. While some of the pricier ones will work pretty well, all of them will have issues with reception and setting them up is usually a pain. I've had expensive ones as well as cheap transmitters and I've wound up returning every single one usually for poor sound quality as well as other issues with the units. Personally, if you want to do it right, just mod your car (if applicable) to direct connect your iphone to your headunit and you'll be far better off than you would with the transmitters.
  12. joudbren macrumors regular

    Apr 13, 2007
    Edmonton, Alberta, Canada
    I just went through this as well. I had a Motorola T505 visor mounted bluetooth hands free unit that also included a wireless FM transmitter. In my area it worked pretty darn well but the audio quality left a little bit to be desired. Don't get me wrong, it was "ok" for sound quality and about the best I've heard for FM but it doesn't compare to direct hookup. It supported A2DP stereo over bluetooth so it could stream music and gps commands as well from my iPhone4 with no physical connection required and of course gave me hands free calls in the car.

    I ended up going with the Apple component video cable which has RCA audio jacks and a USB plug for charging. It plugs into a cheap USB lighter socket adaptor and the rca jacks are plugged into a cheapie rca to mini-din plug adaptor for the aux input. I buried everything in the console so it looks nice and neat and works perfectly.

    Since then I've found that you can get MUCH cheaper cables that offer the USB connection for charging and the mini-din audio connector out already included for the aux connection. Here is an example on ebay:

    I would have went this route if I knew it existed but I'm happy enough with my Apple cable setup and the white cable looks kind of cool in my car's grey interior. Also bought a ProClip adjustable cradle with pass-through connector so I can leave the cable attached to the bottom of the dock and just slide my iPhone4 in and out of the cradle when I get into the car.

    They sell custom mounts as well for almost any car. Their stuff is kinda pricy but very well made so I'm happy with the solution now. Cheers!

    P.S. Of course this all assumes that you have some sort of AUX connector on your factory stereo or RCA inputs available on the backside of the radio.

  13. Plutonius macrumors 604


    Feb 22, 2003
    New Hampshire, USA

    I disagree with the comments about FM transmitters. I own a Griffin iTrip FM transmitter and it works very well.

    1) It's very dependent on where you put your iPhone / iPod. If you put it on the dash or the seat, it doesn't work well. If you put it next to your radio, it can work well. Proximity to your radio is the most important thing for an FM transmitter.

    2) You need to pick the correct FM frequency and it can initially take awhile switching frequencies before you find one that you like.

    If you get a new car, I would certainly invest in a direct connect. Otherwise, I would get an FM transmitter.
  14. rspeaker macrumors 6502

    Jan 1, 2006
    I own a Griffin iTrip FM transmitter and it works fine, too. Sometimes there is excess static, and occasionally I get the buzzing from the iPhone (is that TDMA interference?) but it works really well the majority of the time.

    In my experience, the antenna in the car is key. In my Kia, if the antenna is up, reception stinks. When it's down, it's like listening to an FM station. I found the same thing in my Ford Taurus.
  15. hipvamore macrumors regular

    Jul 2, 2008
    idk about the iphone 4 but usually i have so many noise interference problems with the ones that plug in the 30 pin. try to find one that goes in the headphone jack in my opinion. better sound quality
  16. Jumpman2033 macrumors regular

    Jun 27, 2010
    I'm going to have to do some research on my factory stereo. I'm thinking it might cost about the same to just buy a decent stereo with auxillary input than buy the necessary cables and to cut an extra hole in the dash. I'm sure i can buy a decent one for $100 - $150. I don't blast my radio and have already installed new sony xplode speakers.

    I don't have problems with FM Transmitters in my area, my problem is that i use a speck candyshell on my iphone and never take it off. I don't know of any FM Transmitters that would be compatible with my case. If anyone knows of any, please let me know.
  17. esadb macrumors 65816


    Nov 29, 2008
    Anyone got any good EBAY alternative? I tend to like to make my purchases on ebay :)

    Nice and cheap!

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