Good iPod car stereo adapter?

August 24, 2005 8:07 PM

Why are the iPod adapters for broadcasting my iPod through a signal on the radio so crappy? Is it a law that the broadcasting signal can't be strong at all? And more importantly, does anyone have a recommendation for a good broadcaster for my iPod (For use in my car.)

I've tried 3 and they all suck. They stick way off the iPod, turn on too easily by mistake while in storage (wears the battery down) or they are a PITA to use (too hard to configure or change the frequency while music is playing) and they ALL don't broadcast strong enough so there's always static, especially in the city or on a bridge. Help! Our new car only has a CD player so I can't use a tape adapter anymore.

posted by aacheson to media & arts (31 comments total)

Yes, there are FCC limits on broadcast power on non-licensed devices. It's very low power. I use one in the car, however, you'll notice a big improvement IF you are able to lower your car radio antenna. MOst new cars seem to have done away with the raising and lowering antenna angle in favor of built in the glass antenna or simple non lowering screw in antenna. ( those can be unscrewed to improve your Ipod transmitter signal. I've been podering a switch for the antenna line in one vehicle to disable it when I want the pod transmitter to run. Oh, I'm using the transmitter made by Monster after trying several.
posted by Agamenticus at 8:19 PM on August 24, 2005

I use Monster too, and like it.
posted by iconomy at 8:24 PM on August 24, 2005

Monster makes the iCruze if you want to spend the money. It hooks straight in to your car's stereo system. Additionally people have said that you get better reception if you use a car charger as well.
posted by mrg at 8:26 PM on August 24, 2005

I bought an iTrip last week and indeed, it sucks. After doing some research I've learned that... well, what Agamenticus said. Limits on broadcast power, lower the antenna, etc. I bought mine for indoor use in my living room. It blows so bad I've put it on CL.
posted by dobbs at 8:27 PM on August 24, 2005

The first problem is the FM capture effect. When two AM signals, close in frequency, appear, you'll pick up both signals. When two FM signals are present, close in frequency, the stronger one wins -- and the weaker one goes away. You really notice this when the two signals are close in strength, and the radio jumps from one to the other.

So, if you're in an FM dense city, like Chicago, loaded with very high power transmitters installed on very tall towers (with names like "Sears" and "Hancock"), your little 50mW transmitter is having a real hard time winning.

The second problem is the antenna on the radio. It's hooked to the radio via coax cable. It's also usually outside of the car. For most FM use, this is correct. For you, it means that in between you and the antenna is a large amount of steel.

Unplugging the external antenna, and plugging in a bit of wire into the raido's antenna jack would mean you'd have a much better chance of getting a decent signal in. This is how CD changers interface to the radio on older systems -- they have a low power FM transmitter, and they plug right into the radio's antenna jack. There's a bypass jack for the regular antenna, so when the CD player is off, the regular antenna sort of works.

The right answer, however, is to avoid FM altogether. I use a box that interfaces my ipod to my (factory Honda) radio -- by lying to the radio and saying "Really, I'm a CD changer. Honest!"

It works great, and since it's using the line out, rather than the headphone jack, and it runs that signal right into the amp, rather than the FM block, it sounds great.

FM transmitters are only worth the time and money if there is no better way to do it, frankly. The only way to make them sound decent is to significantly up the effective radiated power -- better antennas, better amplifiers, more power. However, that's not legal.
posted by eriko at 8:36 PM on August 24, 2005

FM's 15 kHz limit sucks. Use a cassette adapter until you get a car stereo that has an aux input. If you already have an aux input but it's in the rear of the head unit, then just route a cable around to the front where you can plug your iPod in. FM is awful.
posted by intermod at 8:39 PM on August 24, 2005

I use the General Electric (or Emerson) EWT950 which can be bought in Radio Shack and dozens of other chains for cheap. I paid $12 for mine. It works great for me--though it does have a button that would turn on too easily in a bag or pocket. Takes two AAA batteries that you can just remove when you're not using it. Beats every complicated solution I've seen. You don't have to load anything in the iPod.
posted by Mo Nickels at 8:40 PM on August 24, 2005

I did this to my itrip with very good results. I now get at least 20 feet of near perfect reception on my car radio.

http://members.shaw.ca/jeffmik/itrip.jpg
posted by jeffmik at 8:51 PM on August 24, 2005

My dad has an iTrip and it works fine. If the signal seems to get weak (presumably because there's a strong broadcast at that frequency nearby), he can usually tweak the settings until there's a better, unused frequency.

Then again, we're in the suburbs.
posted by danb at 8:54 PM on August 24, 2005

http://hobbytron.com sells stronger transmitters.
posted by mecran01 at 10:04 PM on August 24, 2005

I can second what mrg said about using the car charger with the iTrip. It definitely improves my reception. But it still sucks. I'm getting a stereo with an aux input in the front.
posted by sklero at 10:12 PM on August 24, 2005

Hey, eriko, could you provide some links for the Honda setup you mentioned? I'd like to be able to use my iPod in a 2005 Civic Hybrid, and don't know where to start (but don't want to go the transmitter route).
posted by lesingesavant at 11:57 PM on August 24, 2005

Strange, my iTrip as is was able to get about 15ft range just fine. Not always but most of the time.
posted by furtive at 4:24 AM on August 25, 2005

I've noticed car-to-car variability with the iTrip. It works noticeably better in my wife's car than in mine, regardless of the frequency used.
posted by shoos at 4:37 AM on August 25, 2005

Generating a proper stereo FM signal takes quite a few stages, meaning lots of components, expense, and bulk. So these portable transmitters don't generate a proper stereo FM signal, they fudge it in a harsh manner that generates a lot of artifacts, which creates that peculiar (poor) sound you get from the transmitters.

I suspect (but am not sure) that pretty much any stereo FM transmiiter in the sub-$40 range, and many, if not most in the sub-$100 will use the same FM-transmitter-on-a-chip IC (more accurately, clones, variants, and updates of the now-discontinued BA1404 chip), because it's cheap, small, power effective, simple, does the job, etc etc.

The only problem is that it's sound quality sucks, because it fudges the stereo, as mentioned.

This page explains how the stereo should be generated, how it is fudged instead, with plenty of graphs to show and explain the effects on the soundwaves that result

This page explains what the BA1404 chip does, it's shortcomings, and it's use (and abuse) in products.. The IC that is the heart of your transmitter won't be a BA1404, but I think it will be clone or modern version of it.

Can you open up your transmitter and ID the chips? That would be a sure way to find out how it is multiplexing the stereo, how many external stages or filters are needed for proper operation, and eyeballing how densly packed with components the circuit board is and how big it is, can give a rough idea of whether the filters are actually in place, or have been skimped on to save space or money.

But what it boils down to: doing stereo FM transmission on the cheap, and/or in a tight space, generally means sacrifices in the sound.
posted by -harlequin- at 4:44 AM on August 25, 2005 [1 favorite]

Crap, I thought you were asking why they sound crappy, but on re-reading the question, you're talking about crappy ergonomics and crappy range, the other big problems with these things.

Oops.
posted by -harlequin- at 4:49 AM on August 25, 2005

Hobbytron sells bigger, more powerful transmitters. I suppose you could stick one under the seat. But a $100 stereo with an aux jack would cost the same or less, and be more elegant.

You could also install powered headrest speakers that you jack into directly with the ipod.
posted by craniac at 5:17 AM on August 25, 2005

I was frustrated with FM transmitters so I just bought a new car stereo from Best Buy with an aux input jack and listen that way. I was replacing a not-so-great stock 6 yr old VW stereo, so it wasn't a tough choice. I spent under $200.
posted by jdl at 5:41 AM on August 25, 2005

This is what I used for my Jetta. It connects to the cd changer interface in the trunk and I just ran some RCA cables up to the center console. It sounds great, and was really easy to install. Crutchfield has one of these adapters for just about every recent make of car.
posted by PantsOfSCIENCE at 5:55 AM on August 25, 2005

You can get one of these that plug directly into your car stereo's antenna input. They're not too bad; they sound better than a tape adaptor. They can be a pain to install, though. There are also tons of products to wire in an iPod directly to a factory radio.
posted by zsazsa at 5:56 AM on August 25, 2005

I had bought an AirPlay to replace my aging iRock, but returned it - the iRock sounds much better, even though it eats batteries (I don't think that it uses that IC like the newer, smaller transmitters do).
posted by rfs at 6:34 AM on August 25, 2005

What I want to know is, why isn't an audio-in jack standard on all car stereos? I can't imagine it adding much more than $5 to the production cost.
posted by mkultra at 6:39 AM on August 25, 2005

You may want to look into a NewerTech RoadTrip! transmitter. They only transmit on one frequency (your choice of either the 87.9 or the 107.7 model), and do it pretty reliably. I've used the 107.7 model on a trip through New England (from Portland, Maine to Connecticut) and never experienced much in the way of static or signal loss. No battery worries, since it plugs into the car's lighter jack.

It's not perfect, and I'm sure it's no replacement for a direct line-in connection, but it is a pretty cheap way to get sound that doesn't completely suck.
posted by anthom at 7:07 AM on August 25, 2005

What I want to know is, why isn't an audio-in jack standard on all car stereos?

Because the company the OEM parted out the job to doesn't want competition--i.e., Panasonic makes a deal with Ford to build their new 2006 Majesta car stereo, and offers a CD-changer/Sirius Satellite system upgrade (for more money). Now you have to buy Panasonic/Ford's kit if you want to use it with your factory HU (head unit), for a substantial mark-up. Vendor lock-in blows.

I'd do what most people here have recommended: get a new head unit with aux-input. There are hundreds to choose from for pennies on the dollar. Just don't buy a brand-spankin' new one unless you've got money to burn. There are always those people who need the latest and greatest DVD-fold-out-screen-with-built-in-5.1-stereo-surround-etc. that will sell their old gear on eBay at huge losses.
posted by Civil_Disobedient at 7:10 AM on August 25, 2005

PS: the General Electric (or Emerson) EWT950 has worked more than 25 feet through three walls and on the road in a large truck. It's cheap, it's easy to use, and it broadcasts anywhere on the FM band. I don't know why people bother with the more expensive or complicated solutions.
posted by Mo Nickels at 7:12 AM on August 25, 2005

You might also be running into the problem that FM is crappy to begin with. You're going to get some signal loss and compression of your music and it's never going to sound as good as it would if you were hooked in directly. I'd say that connecting directly to the head unit would be the best option, followed by a tape adapter, then one of those kits that includes a FM modulator but connects into the antenna line from inside the car. Barring all of those, you can try using a FM broadcast thingy like you are and just unscrew your car antenna.
posted by mikeh at 8:04 AM on August 25, 2005

lesingesavant, I got one of these and was able to intall it myself in my 05 (non-hybrid) Civic. It works just fine.
posted by transient at 9:18 AM on August 25, 2005

For what it's worth - ie, if your car purchasing decisions would be impacted by such things - my girlfriend's new beetle convertable has a line-in jack subtly hidden on the underside of the dash. After liberating my belkin power/sound adaptor she was ready to go.
posted by phearlez at 9:25 AM on August 25, 2005

I have a GM Head Unit in my 2005 Pontiac Vibe, but I also have XM Radio built in from the factory.

If I change out my head unit, do they have to run a whole new attenna to get XM to work? I was told by a couple of people that XM and CD Changers don't cooperate with the head unit, so I couldn't use my AUX port on the head unit for my iPod.
posted by benjh at 10:10 AM on August 25, 2005

We have a brand new Volvo V50 with those sleek panels in the front and I don't know if I could juice it up with something directly into the stereo. (BTW, when we bought it they said we could have the IPod adapter put into the volvo in about 2 weeks when they started doing it.However, it's not for the V50, on the V70. Grrrr.)

However, it sounds like you can make it think it's got a CD changer...how do I go to a stereo store and "ask" for that?
posted by aacheson at 11:25 AM on August 25, 2005

I don't know if I could juice it up with something directly into the stereo

You can't with the V40/V50. No CD/AUX inputs on the stock radio. Unfortunately, the radio is kind-of "embedded" into the dash, which precludes installing another radio in its place. Pretty annoying, if you ask me.

What you *might* be able to do is replace the stock headunit with one from a V70, though I don't know if it's a direct swap.

Or, you could install an external amplifier, then patch in an aux-input into the line-in for the amp that you could toggle with a switch.

Or(!), you could directly patch into the FM antenna jack, so the FM modulator would work without interference (or at least, not much... but certainly heads above the iTrip). This guy sells instructions for doing so.
posted by Civil_Disobedient at 1:25 PM on August 25, 2005