There’s a certain category of products that we never enjoy writing about or testing, and that’s FM transmitters. These wireless iPod-to-radio devices upset almost as many people as they satisfy, and despite an abundance of options, rare is the day when a person settles on one as truly superb for all applications.
So we’ve continually caveated our reviews with a prominent warning: static is an unavoidable consequence of FM transmission, and if you have any way to run a wire or a cassette adapter between your iPod and your stereo system, do it. In many cases, it’ll be cheaper, and sound better. FM transmitters won’t work much if at all from a distance greater than 30 feet from your radio, and typically won’t sound very good at a distance greater than 10 feet away.
But that doesn’t stop people from needing or buying FM transmitters, companies from manufacturing them, or us from testing them. We’ve run more than a dozen FM transmitter reviews in the past, but the landscape has changed a lot since our first review back in 2001, and an A product back then isn’t necessarily an A product today. So with the fourth-generation of iPods most likely nearing its end, we wanted to do some sort of meaningful comparison of the best options currently available.
There was an initial set of problems. Because of dramatic variations between device features and limitations, local radio stations, and even optimized iPod settings on a per-transmitter basis, there’s no good way to do a perfectly fair test of all transmitters, with a guarantee that the results will be generalizable to any reader’s particular situation. For example, some devices only tune to one station – 87.9. Others tune to any station except 87.9. Some devices are portable. Others work only in a car. And so on.
But we tried. And the findings below are intended to give you an idea of what we heard when doing a comparative test of 12 of the best FM transmitters available, attempting to hold as many factors constant as we could. A current-generation 20GB color iPod was used as our test device for every FM transmitter except Belkin’s iPod mini-only TuneBase FM, where we used an iPod mini with the same songs. Regardless, we note that many of the devices are capable of shining under specific conditions that may or may not be reflected by using an averaging method. Our earlier individual reviews of these products do a much better job of explaining those conditions.
There’s one other serious caveat. Because of an unfortunate industry practice whereby companies quietly tweak their accessories after release, the transmitters we (and other reviewers) have tested may vary from the ones you go out and purchase. The variance could be good, or could be bad. Many companies have tried to make their accessories better, but others have tried to find ways to make them cheaper, compromising on quality at the edges. This practice accounts for some of the variation we’ve seen between user experiences and our own.
Except for devices that required 87.9FM, we tested using a semi-challenging local station, 103.3FM, and began our tests in a car. The car’s volume was set digitally to 40 for all 12 of the transmitters, and each transmitter was given an opportunity to broadcast silence and music at that volume level, which is high enough to allow every device to exhibit clearly audible static. Regular listening takes place between 20-25 in the closed car. The iPod was positioned at arm’s length from the driver, near the radio, but several feet from the car’s rear-mounted antenna – normal usage conditions.
We then tested all six of the transmitters capable of indoor performance with a home stereo system on 103.3FM, setting the stereo’s volume digitally to 50 for each one. (A volume level of 50 on our system is quite high – normal listening would be closer to 30-35, depending on ambient noise and other factors.) Only one of these six devices required 87.9FM (or a nearby station), so we tested that one on that station. In all cases, the iPod was positioned at a distance of approximately three feet from the radio’s FM antenna – our normal usage conditions. An iPod could be expected to perform worse than this at greater distances.
Six of the devices we tested are only for use in a car. Three of them combine charging, FM transmission, and mounting into a single device. Three do not. They are:
Belkin’s TuneBase FM: An all-in-one charger, transmitter, and mount with a line-out option. Our B+ rating most strongly recognizes the unit’s slick gooseneck design, which we prefer to all other integrated charging/mounting solutions we’ve seen. Our original review of TuneBase FM rated it a C+ because of audio issues that were largely remedied in a revised version of the product, which was tested here. We were very surprised when it had the hardest time of all car-only devices with 103.3FM.
Performance: TuneBase FM exhibited the most noise of any of the options we tested when silent, and when music was playing, we could hear both very audible static and noticeable bass distortion.
DLO’s TransPod FM (Current Version): An all-in-one charger, transmitter, and mount with a line-out option. TransPod has benefitted the most from iterative tweaks over time. While we do not prefer its mounting apparatus to the TuneBase’s, we have found its FM transmission quality to be good.
Performance: TransPod exhibited audible static when the iPod was completely silent, and a bit of static and bass clipping when music was playing. However, it was superior to the TuneBase FM by a noticeable factor.
Griffin Technology’s RoadTrip: An all-in-one charger, transmitter, and mount. We pilloried the RoadTrip (iLounge rating: C+, not to be confused with a similarly named product line from Newer Technology, below) for awkward design and some needless options. But we liked its FM transmission, and found that it had an edge on TransPod. It is likely, though unconfirmed, that newer revisions of this device improve upon the audio of the version we received a year ago.
Performance: RoadTrip exhibited a low hum and audible static when the iPod was silent, but the static level was a little lower than DLO’s TransPod. A comparable level of static and bass distortion was evident when music was playing.
Kensington’s Digital FM Transmitter/Auto Charger: An FM transmitter with integrated iPod charging but no mount, Kensington’s product scored very well (iLounge rating: A-) in our recent review for delivering dynamic audio and a low noise level on its best stations. It had a tougher time on 103.3 than we expected, but still delivered powerful audio.
Performance: While static here was audible when the iPod was silent, the Digital FM Transmitter sounded very strong and dynamic when the music was turned on, with light static and issues only with sibilance (static on S sounds). Because of the strength of the music signal, Kensington’s unit could be turned down to a lower level than the others, reducing apparent static while still sounding equally powerful in music level. Among our top performers, even though 103.3 was not its strongest suit.
Newer Technology’s RoadTrip! Plus: An FM transmitter with integrated iPod charging but no mount, RoadTrip! Plus is one of the least expensive such solutions we’ve tested. Though it puts out a very good signal on its only station, 87.9FM, the unit we received exhibits cable noise when moved, a problem we were later told was fixed at the last minute in consumers’ units, but yet was reported to us by readers thereafer. Mostly because of its aggressive price, its B+ rating would have been higher if not for the cable issue.
Performance: Though the static level was low on 87.9 when music was silent, a slight high-pitched sound could be heard. When music was turned on, it sounded powerful, though a high-pitched warble could be detected at the high 40 volume level. Cable sounds also pose somewhat of an issue.
Newer Technology’s RoadTrip! 87.9FM: An FM transmitter without charging or a mount, RoadTrip! 87.9FM is the least expensive of the options tested, yet one of the best sounding overall. Part of this is due to its exclusive use of an all but guaranteed-to-be-empty radio station, and its lack of a Dock Connector connection to the iPod makes it unique amongst car-only FM transmitters – as well as a problem for people whose iPods aren’t charged before they enter their cars. But it’s undeniably good sounding, if not quite as dynamic as Kensington’s offering.
Performance: A low static level during silence and very little apparent static during music playback made this one of our top performers, limited mostly by its connection to the iPod’s headphone jack and requirement that the volume be adjusted to an appropriate level. While benefitting from its use of a station more clear than 103.3, it sounded very good regardless.
Fully Portable Competitors
The remaining six devices are portable through one means or another. They either run off of the iPod’s internal battery or require their own. This collection of transmitters went through a second test indoors after the first in-car test, where results in some cases varied, and in others stayed the same.
Belkin’s TuneCast II: One of only two portable FM transmitters to dangle from the iPod’s top, TuneCast II has an integrated LCD screen and requires its own AAA batteries, which it drains prodigiously. While it was rated B+ in early 2004, subsequent superior competition has worn that grade down to a lower level in our minds.
Performance: A very audible static level persisted from silence through music playback in the car, only to improve a little bit when tested indoors. Bass clipping was more notable indoors than the static level.
BTI’s TuneStir: The only other portable FM transmitter to dangle from the iPod’s top, TuneStir (iLounge rating: B-) is the second most expensive portable FM transmitter of this group, and is better known for its ability to tune in FM radio and act as an iPod remote when you’re out and about. But in a car or a home, it also works as a FM transmitter, though its interface isn’t as easy as most other alternatives.
Performance: With static that was above average but not at the TuneCast’s level during silence, the TuneStir’s music signal was interrupted by static oudoors. Indoors, however, it improved markedly, with only an occasional high-pitched noise during silence and a static level during music playback that was less noticeable.
Griffin iTrip (original): Generally considered to be the dean of all iPod FM transmitters, Griffin’s iTrip amazed iPod owners with its small size, quality FM transmission, and innovative on-iPod-screen tuning mechanism, as well as its ability to toggle between international and US broadcasting. However, its earlier A- rating has recently been undercut by LCD screen-equipped competitors. Our photo shows the classic 1G/2G iTrip, but we tested with the most recent iTrip available – the iTrip Black designed to match U2 Special Edition iPods.
Performance: Despite its tuning challenges, which made the original iTrip less enjoyable to use than any of the other devices we tested, the unit remained one of the better portable units we tested. In a car, it displayed above average static when silient, yet although the static was noticeable during music, the songs still sounded good. Connecting iTrip to a car charger at the same time improved its sound quite a bit, reducing its static levels to only audible and slightly noticeable, respectively. Indoors, it exhibited an bit more than an audible level of static when silent and when playing music, but sounded good regardless.
Griffin iTrip LCD*: Not yet released in stores, this LCD-laden version of Griffin’s iTrip offers two broadcasting modes with different levels of noise reduction, US and international tuning, and a super-simplified tuning dial, all in a package perfectly matching full-sized iPods. However, we have held back on reviewing this version of iTrip because of questions over the performance of our review units, which because of a possible manufacturer slip-up may or may not be representative of actual shipping product. As such, the new iTrip has no product rating and bears an asterisk, but we included it in this comparison mostly out of curiosity.
Performance: iTrip LCD exhibited major problems outdoors when tested on 103.3 without a car charger attached. It had problems overwhelming the limited broadcasting that was coming in on 103.3 with either of its noise reduction modes, and we would not characterize its audio as listenable. A car charger made it partially listenable, but not great. However, indoors, its better noise reduction setting produced a static level during silence that was noticeably below the average level, while its standard setting produced sound similar to the original iTrip. When music played back, though, it sounded surprisingly clean. We have been told that reviewers may accidentally have been shipped screwed up units from a small rejected batch of iTrips, so we will have to revisit its performance later. Based on conflicting information we’ve received, we can’t decide whether it’s about to become a top-ranked portable solution or an also-ran.
Tekkeon MyPower FM: This portable FM transmitter is unique in that it connects to both the iPod’s bottom Dock Connector port and a standalone battery pack, requiring both for power. It is therefore the most expensive option we’ve tested when all factors are considered, and received a B- rating largely on the impracticality of its design by comparison with numerous less expensive options.
Performance: Though its static level was average, a high-pitched sound could be heard during MyPower FM’s silent moments, and static and bass clipping were evident during music playback outdoors. Indoors, its performance appeared to be identical to its outdoor performance.
XtremeMac AirPlay: This tiny FM transmitter was the first to mount fully on the iPod’s top with an integrated LCD screen, and its performance at the time of review earned it our very rare flat A rating. However, we have received numerous user complaints over high-pitched squeals in the audio of shipping AirPlay units, and we have heard those noises ourselves in the subsequently released AirPlay shuffle, as well as in our own unit on occasion. AirPlay exhibited the noises indoors when we tested, but not outdoors.
Performance: AirPlay’s performance was very similar to iTrip LCD’s without a charger – unlistenable on 103.3 because of problems overwhelming the station. But when a charger was attached, its static level became okay. Indoors, its static level was average, but a high-piitched sound appeared during both silence and music playback. The static level was less noticeable during playback, however, and it sounded good other than the static. Our feelings on AirPlay are twofold: our review unit does better on other stations than this one, and other users’ units may not be as good as the one we have. Despite our review, and based on considerable subsequent information, we continue to recommend caution when considering the AirPlay – buy it only from a store with a good return policy.
Because of lingering questions as to the actual performance of production model iTrip LCDs, it’s hard to predict what the best of the portable FM transmitters will be several weeks from now. Under certain conditions, the current model performs surprisingly well, but under others, it has major issues, as do most of the other portable solutions. Most iPod users have some way to connect their iPods via cable to a home audio system, and we continue to recommend that they choose this course of action if at all possible. Though we can rate these FM transmitters relative to each other, we’re not sure that any of them will satisfy a discerning listener, and even A-rated portable transmitters have issues that will bother many people.
A far superior option for any user without a vehicular cassette deck or line-in option is to buy an in-car FM transmitter. Our top recommendations are Kensington’s Digital FM Transmitter, which comes with a car charger and works well on multiple stations, and Newer Technology’s RoadTrip+, which is much less expensive, has no charger, and works well – but only on one station.
If you really want to try your luck with a portable FM transmitter, consider buying a separate car charger such as Griffin’s PowerPod or PowerJolt. You’ll find that their combination with any transmitter will improve the iPod’s broadcasting ability and clarity. And remember to test a number of stations and volume levels before giving up. Each portable FM transmitter except for MyPower FM has peak volume settings that vary from 40-75% of an American iPod’s top volume level. iTrip LCD does some (if not quite perfect in our unit) automatic volume regulation, but the others do not.
As always, we welcome your comments and stories of your FM transmitter experiences, below.