Review: Sonnet Podfreq FM Transmitter

Pros: Broadcasts a FM stereo signal on your choice of frequencies.

Cons: Large, unwieldy, hard to charge iPod while inside, costs two or more times as much as competitors, doesn’t outperform them.

“Fat, drunk, and stupid is no way to go through life, son.” Animal House had the right idea twenty-five years ago, and while the quote needs to be paraphrased into other contexts, there’s no doubt that it applies to consumer electronics products, as well.

While it pains us to say it, the first iPod product by longtime Apple upgrade and adapter maker Sonnet Technologies is the archetypical fat, drunk, and stupid iPod accessory: the Podfreq FM transmitter is a bulky, expensive, and technologically underwhelming product by comparison with competing and established products. Most amazingly, one of the Podfreq’s design errors even limits its ability to be used for long stretches in a car – a problem we never would have expected in a $99.95 “premium” FM transmitter. If you’re interested in learning just what went wrong with this product, read on.


Like Griffin’s iTrip and Belkin’s TuneCast II before it, the Podfreq turns an iPod into a portable radio broadcasting device, and is capable of overwhelming any empty FM radio station chosen on a LCD screen. Unlike the iTrip but like the TuneCast II, the Podfreq doesn’t use the iPod’s screen for tuning, instead including its own LCD for the sole purpose of displaying the current frequency it’s taking over. And as a contrast with both competing devices, the Podfreq’s LCD is not backlit, which could make for a bit of a struggle when channel surfing in a dark car.

Review: Sonnet Podfreq FM Transmitter

As a general rule, iPod accessory manufacturers have gone to unusual lengths to miniaturize and coordinate their accessories, and the FM transmitter category is no exception to this rule. Because it uses the iPod’s LCD, Griffin’s iTrip adds almost nothing to the size of an iPod, and even Belkin’s comparably larger TuneCast II is only a bit chunkier than a stopwatch.

Sonnet’s Podfreq is in a different size category altogether. Best described as an iPod enclosure, the mostly plastic casing surrounds the top, bottom, back and sides of the iPod, sealing shut with a metal hinge. A hole in the case’s top permits hold switch and headphone port access; there is no protection for the iPod’s screen or controls. Two soft spacer pads adjust the compartment’s hold on different-sized 3G iPods.

Review: Sonnet Podfreq FM Transmitter

More distinctive is the presence of a large metal antenna that juts out of the Podfreq’s back, extending a wandlike six inches from the top of the already five-and-a-half inch tall case and creating a nearly one foot tall accessory at maximum broadcasting extension. Apparently designed to stand up rather than lie down, the Podfreq includes a swiveling clear plastic bottom piece that rotates out to form a perpendicular cross, thereby keeping the entire enclosure standing vertically. The rear of the Podfreq wasn’t designed to rest on a flat surface, and tilts uneasily left or right when placed on one.

Though Sonnet includes a soft carrying pouch with each Podfreq, the device’s alternating clear and white plastic enclosure components don’t appear to have been designed to withstand use or jarring as a protective case, and to its partial credit, Sonnet only describes the Podfreq as a “dock substitute,” not a case. Inside or outside the carrying pouch, we don’t think that we would trust the Podfreq in a backpack filled with books or other heavy items.

When inside the Podfreq, the iPod rests on a Dock Connector plug and interfaces with FM transmitter circuitry located immediately below. A total of three buttons (power, tune up, and tune down) sit under the iPod’s scroll wheel, and the power button can be held in to set an auto-off timer for 1, 2, 3, 4 or 8 hours of playback. Unusually, the power button lights up briefly when the unit is turned on, but turns and remains off shortly thereafter for power consumption reasons.

Review: Sonnet Podfreq FM Transmitter

Notably absent from the design are either an AC adapter or batteries. Even more notably, there’s no port for a Dock Connector cable – the Podfreq draws power from the iPod itself (albeit a relatively small amount), won’t run on batteries, and doesn’t include a charger. Rather, Sonnet chose to put one Firewire port and one mini USB 2.0 cable port on the Podfreq, and nothing else.

At this point, we must note that we will rarely use the word “idiocy” to describe a product design; the word is reserved only for gross mistakes on the scale of Nokia’s sidetalkin’ and otherwise ridiculous gaming-phone-MP3 player N-Gage. But as iPod accessory aficionados no doubt have gathered from the red flags “enclosure,” “large metal antenna” and “no port for a Dock Connector cable,” the Podfreq comes precariously close to a design tragedy of N-Gage proportions.

Want to use the Podfreq as a “dock substitute?” Go out and buy a new cable. No, not the ones Apple sells for 3G iPods, but you know, one of those mini USB 2.0 to standard USB 2.0 cables so that you can plug it into your computer. And while you’re at it, go and get a Firewire to Firewire cable so that you can charge your iPod while using it. Want to use the Podfreq in your car? Don’t forget that you’ll need brand new – or should we say now old and possibly discontinued 1G/2G iPod chargers just to use the Podfreq in a vehicle, because the enclosure won’t connect with all the current iPod chargers that include – no surprise here – Dock Connector plugs, not Firewire plugs. But this assumes that you would even want to have a half-foot antenna sticking up inside your car while you’re driving.

Of course, these just aren’t issues with Griffin’s iTrip or Belkin’s TuneCast II, both of which work with the iPod mini (unlike the Podfreq) and, depending on the version purchased, are also available for older 1G and 2G iPods. It also goes without saying that both of these competing devices also happen to be available for less than half the Podfreq’s price. The real question, then, is whether Sonnet’s design offers anything that its competitors do not.


Sonnet’s design can be charitably described as underwhelming, but we suspected that some users would accept it – flaws and all – if the device in fact delivered on its major promise: it claims to be a “premium” FM transmitter that sounds “superb” with an “advanced audio design” that “ensures superior music quality.” We therefore tested the Podfreq to see whether Sonnet’s claims were borne out in comparative testing.

Review: Sonnet Podfreq FM Transmitter

In short, they were not. We tested the Podfreq directly against both the iTrip and the TuneCast II both indoors and outdoors, using multiple radio frequencies and different stereo radios, one digital and one analog. Because we were so surprised by our results, we decided that two different editors in total should repeat the tests from different locations, just to achieve greater comfort with our conclusions. And they didn’t change.

Under the best circumstances, namely when there was an empty FM radio frequency and when the Podfreq’s antenna was fully extended, we found that the Podfreq performed almost identically to the other two devices, which is no great surprise because the specifications of all three products are nearly identical, limited primarily by FCC regulations. On a good channel, stereo separation, distortion, and overall audio quality sounded almost exactly the same between them, though we sometimes heard static pops in the Podfreq’s signal that weren’t there with the TuneCast II or iTrip.

We will note that under very limited circumstances, the Podfreq appeared to have an ever-so-slight range advantage – typically at a distance at which all three devices were putting out static-filled, mediocre audio. The best thing we can say is that if you’re looking for a device that may – and we repeat, may – give you an extra three or four feet of noisy, garbled audio, you might want to give Podfreq a try.

But there were significant differences between the devices on bad channels, and not positive ones for Sonnet’s product. Indoors on a bad (not entirely empty) channel, we found that the position of the Podfreq made a considerable difference in its broadcasting capabilities, occasionally limiting the device’s ability to overwhelm a radio frequency unless it was right next to the radio’s antenna. Outdoors in a vehicle, we found that both the iTrip and TuneCast II generally did a better job of locking on to stations and broadcasting clear signals, though all three devices delivered solid (but sub-cassette tape adapter quality) stereo audio.

Review: Sonnet Podfreq FM Transmitter

(As a side note, both competitors offered tuning to the 107.9 frequency not supported by the Podfreq, and the iTrip more significantly offered expanded tuning capabilities compatible with Japanese radio stations.)

Some might assume that since the Podfreq interfaces with the Dock Connector, the aggregate audio output might sound superior to the headphone jack-mounted iTrip and TuneCast accessories, but that’s practically not the case. None of the FM transmitters creates a crystal-clear signal that’s as good as a strong digital FM radio station, and certainly not approaching line or CD quality for that matter. Good cassette tape adapters sound considerably better, and direct audio lines into car head units and stereos are a step or two beyond that. Consequently, choosing localized FM transmission for any sort of “premium” audio quality is not a winning proposition.

On a positive note, the Podfreq’s battery drain did not appear to be significant. While iPod battery tests aren’t scientific, our test units typically draw around seven hours, 40 minutes without accessories attached. With the Podfreq strapped on, our test ran for a bit over seven hours, suggesting that the device only detracts 30 minutes from a fully charged iPod’s juice, give or take 10 minutes. This isn’t a problem in and of itself, but as we found when we first went to test our iPod and the battery was drained from earlier use, there was no way to use the Podfreq with the iPod until we recharged the unit – we didn’t have a dual Firewire cable or old-style car charger handy. Because it enclosed the iPod in a shell and removed external Dock Connector accessibility rather than plugging into the top of the unit, the Podfreq temporarily turned our iPod into a very large paperweight.


While it is hard to understate the breadth and depth of the Podfreq’s physical design misconceptions, they could be viewed as an iPod market rookie’s first attempt to design a peripheral that people might find useful. Rather than just duplicating the iTrip or TuneCast II, Sonnet took the time to develop something different, and they’ve thereby earned iLounge’s equivalent of the American Idol John Stevens award: great people, bad performance.

Podfreq is an enclosure that you can’t use as a case, a $99.95 FM transmitter that doesn’t outperform units half its price, and an iPod battery consuming “dock” you can’t keep fully powered at home or in the car unless you buy cables no 3G iPod owner is otherwise likely to own. The former omission is almost acceptable, but the latter two are fatal to the product’s design. Like the fat, drunk, and stupid character in Animal House, the Podfreq is a flounder, clearly too big, costly, and practically limited for us to recommend to virtually any iPod user.

Updated August 4, 2006: More than two years after publication of our original review, Sonnet Technologies sent us an updated version of Podfreq, complete with additional accessories that were later added to the product’s package: a soft carrying bag, an auto charger, two rubber pads, and a mounting bracket with screws and nuts. Pictures of the device, which remains cosmetically near-identical to the version we previously saw, are below.

Review: Sonnet Podfreq FM Transmitter

Review: Sonnet Podfreq FM Transmitter

Review: Sonnet Podfreq FM Transmitter

Review: Sonnet Podfreq FM Transmitter

Table of Contents

Our Rating


Company and Price

Company: Sonnet Technologies, Inc.


Model: Podfreq FM Transmitter

Price: $99.95

Compatible: iPod 3G, 4G

Latest News