After years of resistance, I broke down and bought myself a shiny, black, 30GB video iPod. It wasn't the chance to watch Lawrence of Arabia on a screen the size of a sparrow's pillowcase that won me over; rather, Apple finally added "CD-quality" recording to the popular music player. As a longtime guitarist and field-recording enthusiast, I was intrigued and hopeful.
Even the earliest iPods had rudimentary recording capabilities, but what I heard back then made me long for the glory days of monaural cassette tape. The iPods made after 2005 (except the Shuffles) boast 16-bit, 44.1kHz stereo recording. But is it really possible to record CD-quality audio on your iPod? To find out, I tested three popular add-on mics: the Belkin TuneTalk Stereo, Griffin iTalk Pro, and XtremeMac MicroMemo.
Each connects to the docking port at the bottom of the iPod, includes a built-in microphone, and has an 1/8" stereo input for an external mic or line-level source (such as a mixer or tape deck). Each supports the iPod's two recording resolutions—8-bit, 22.5kHz mono and 16-bit, 44.1kHz stereo. The Belkin and Griffin units handle both full-size iPods and the smaller Nano (second-generation); the XtremeMac MicroMemo comes in distinct normal and Nano versions. And yes, all three come in black.
Sadly, iPods can't record using Apple's terrific lossless encoding format, or even compressed AAC. Instead, Apple chose the WAV file format common to Windows. So be aware that your recordings will take up a lot of room. How much? Figure 10MB per stereo minute at the highest resolution. Still, that's about 48 hours on a 30GB iPod. Ought to be sufficient, eh?
No matter which device you choose, recording on an iPod couldn't be easier. Each device has a button that calls up the iPod Voice Memo screen. A click of the iPod's wheel is all it takes to start recording. (One mic even offers a shortcut for that.) A second click stops the recording and saves it to the Extras menu under Voice Memos. When you sync to iTunes, you're asked if you want to upload the recordings to your computer, where they appear as a new playlist called (ta da!) Voice Memos, all neatly labeled with the time and date.
Alternatively, you can turn on the iPod's external-drive mode and drag the files over. But the WAV files won't display such clear naming conventions once you're outside the iEnvironment. (See Figure 1.)
Fig. 1. You can drag your iPod recordings to your computer instead of transferring them with iTunes, but the file names are hard to read until you realize they're in
yyyymmdd hhmmss format.
Before I discuss each recorder individually, I need to say one more thing: Recording eats up your iPod's battery faster than a puppy gobbles a milk bone. Chances are you'll run out of juice long before you max out the memory. I did a test at high resolution with a fully charged battery. After just 37 minutes, the iPod's battery icon glowed an ominous red. I'd read that you could ignore it, so I did. But the iPod shut down at one hour and 26 minutes.
The good news is that I didn't lose the file, but one-and-a-half hours isn't much when you're recording lectures or meetings. Although I've heard that recording at the low resolution increases battery life, that wasn't my experience.
I made identical test recordings with each mic. First I wanted to hear how they fared with basic close-vocal recording at both low and high resolutions. Then I walked to the far end of my room to hear how well they picked up a voice from a distance in a noisy room. To test each mic's fidelity, I played some guitar. I also tried recording with a mini T-shape stereo mic and a cheapo lavaliere I had hanging around. Lastly, I plugged a studio mic into my mixer and sent the output of my mixer into the iPod mics' line inputs to test how they handled a line-level source.
One of the Belkin TuneTalk's handiest features isn't visible here: a little easel that lets you aim the mics. (Click to enlarge.)
The TuneTalk Stereo comes with a little plastic spacer (allowing you to connect through an iPod's case), a USB cable, and a tiny plastic easel stand. Though it's flimsy and tipsy, you'll appreciate the stand if you need to aim the mics at someone across the room.
The TuneTalk Stereo has a pair of microphone elements for stereo imaging. A small button on the side puts the iPod into record-ready mode, but you must click the iPod's wheel to start and stop recording. A small slider on the bottom toggles between two level settings labeled "Auto Gain On" and "Auto Gain Off/Line In." Actually, the "Off/Line In" setting works fine for loud signals recorded with the mic. The mic is disabled when you plug in an external mic or line-level source. The TuneTalk supplies ample phantom power for small condenser mics. A wee LED acts as a clipping indicator.
The TuneTalk's USB port lets you record while connected to an external power source such as a battery pack or AC adaptor. Given the iPod's abysmal battery performance when recording, this is a great feature.
Here are some audio samples:
As you can hear, the TuneTalk's preamps add a lot of noise, though to be fair, that's true of all three devices. You can also hear the iPod's disk drive spinning up—a problem with both the TuneTalk and Griffin iTalk recorders.
Recordings made with a mini T-mic didn't sound appreciably better. Incidentally, grabbing the iPod to stop recording created loud spikes no matter which recorder I tested. I edited them out to save your ears.
With all three iPod mics, using an external mic and mixer resulted in far better recordings.
The red ring on the Griffin iTalk Pro lights up to let you know you're recording.
The iTalk Pro is simplicity itself. Unlike the others, you can initiate recording by pressing the iTalk button. A red ring lights up to confirm recording—nice!
Holding the button for a couple of seconds lets you access three gain settings: Low (for line sources or very loud signals), High, and Auto. I found the High gain setting best for most uses:
The iTalk is the only recorder with three gain settings. Apparently, Apple neglected to include any way to adjust recording levels so it's up to the manufacturer to implement that.
I next tried the iTalk on my guitar. I couldn't find an easy way to angle the mics to face my guitar, so I laid the iPod flat on my desk. Still, the results aren't half bad:
If you listen closely, you can hear the iPod's hard drive spin up. Using an external lavaliere mic or routing a mic though a mixer eliminated the hard-drive noise.
The XtremeMac MicroMemo comes in both Nano and full-size versions. The base houses miniature speakers. (Click to enlarge)
The MicroMemo sports a monaural microphone on a short, flexible boom. At first I was taken aback: Why mono? Upon reflection, it makes sense. The intended use is for recording voice memos and lectures. Who cares if your history teacher's in stereo?
Even with no way to adjust recording levels, the MicroMemo did a decent job of recording voice:
The guitar recording lacked some of the detail and depth of the others, but made up for it by eliminating the hard-drive noise:
Because of the lack of hard-drive noise, the XtremeMac MicroMemo is the recorder I'd choose for capturing tunes at a jam session.
Although the MicroMemo literature mentioned using external mics, I was unable to find one that worked. A call to tech support confirmed that the MicroMemo supplies 50mV of phantom power to the 1/8" jack, but the tech added that "the rings might not line up properly" with third-party mics. The supplied mic twists into the socket to lock in position; so there may be something to that. XtremeMac's Katie Hathorn subsequently added, "We have tried many condenser mics with our MicroMemos and not had any problem with them. If you are using a stereo mic, it needs to be powered and it needs to be switched to line-in on the MicroMemo."
Tests I did with an external mic and mixer sounded overly compressed and unnatural:
Holding the button on the MicroMemo for two seconds activates tiny speakers. Yep, you can listen to your new voice memos without earbuds—provided the room is very, very quiet.
Each of these devices does an adequate job capturing lecture notes, grabbing a tune on the go, or making quick notes to yourself. All are absurdly easy to use, all have acceptable mics, and each has one unique feature that makes it stand out. I'm hard-pressed to pick a favorite, so I listed some impressions in the table below.
After all is said and done, just how good is the iPod as a recording device? Not very, I'm afraid. Apple dropped the ball by not implementing real-world recording features. Inadequate (or nonexistent) gain-staging; no way to monitor while recording; no MP3, AAC, or lossless compression; terrible battery life... Can you say "afterthought?"
Until someone comes up with a true high-fidelity recording solution, I'll save my iPod for listening to music.
None makes what my nontechie buddies call "clean" recordings; there's just too much preamp hiss even when using external microphones. That in itself would preclude using any of these for field recording or creating podcasts. On the other hand, look at the price!
Of the three, I think the Belkin TuneTalk Stereo's mics have a slight edge in terms of fidelity and stereo imaging. I like the MicroMemo's design, but I wish it had some way to adjust levels. The iTalk's one-button recording is a solid plus.
I was put off by the way the Belkin and Griffin units picked up hard-drive noise. However, both made very good recordings when I used my mics and mixer via the line in. (In fact, somebody's already released a CD recorded this way; check out how he did it.)
But that's not really what these gadgets are all about. If you need an inexpensive way to record memos or lectures on your iPod, any of these mics will work.
|Belkin TuneTalk Stereo||$69.95||USB port for recording while charging. Includes stand.||Picks up hard-drive noise. Can't use stand when connected to USB.|
|Griffin iTalk Pro||$49.95||One-touch recording from iTalk button. Three input levels.||Picks up hard-drive noise. No stand; hard to position mics.|
|XtremeMac MicroMemo||$59.95||Boom stand facilitates mic placement. Doesn't pick up hard-drive noise.||No recording level control. Monaural.|
Mark Nelson is both an acoustic musician and the author of Getting Started in Computer Music (Thomson Course Technology). He oscillates between Oregon and Hawaii, where he co-produces the Aloha Music Camp.
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