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Listen closely: Every minute of the day is filled with amazing sounds--whooshes and gurgles and woody clatters, the sweet murmur of children, the intricate rhythms of machinery. How cool would it be to have a pocket-size gadget you could whip out to capture those sonic seasonings?

For the past few years, I've carried an Olympus V-90 digital voice recorder almost everywhere. As expected, it was great for recording sudden ideas and observations, and even impromptu interviews. The V-90 was especially handy in the car, where I'll often see or hear things I want to remember. Without taking my eyes off the road, I could nab an idea with the flick of a switch and the click of a button.

What I didn't expect was how compelling the voice recorder would become as an audio diary. Because it stamps each recording with the time and date, I could see exactly when interesting sonic events happened. And because the recorder was always with me, I collected a number of seemingly unimportant sounds that are quite poignant in retrospect.

Unfortunately, I couldn't really use those found sounds in music productions except as a special effect: The V-90 had cruddy audio quality, and the only way to get the files off of the device was to record its earphone output or its dinky speaker.

So when the V-90 finally shorted out after I sat on it one too many times, I started looking around for a more modern pocket recorder. High on my list of requirements were higher audio quality and the ability to transfer audio files to a computer. You can read more about the epic search in my blog, but it came down to two options: the Creative Labs MuVo Micro N200 (a RAM-based MP3 player with a voice recorder; $119.99 for 512MB), and the Olympus DS-2 ($149.99). Happily, I was able to try them both, and I have to agree with the blog reader who guessed the DS-2 was a far better choice for on-the-go recording. (See the sidebar "Why Not Use an MP3 Player?")

DS-2 vs. V-90 Out with the old (V-90, right), in with the new (DS-2, left). Sound quality and features have improved dramatically in the six years between models, although the V-90's sculpted case fits more comfortably in your palm and pocket.

The DS-2 also has some slick features that extend its usefulness significantly. In fact, after carrying it in my pocket for seven weeks and making tons of recordings, I found only one major drawback--which may not be a problem for you. Roll tape! ...Er, chips.

All This and DS-2

Most voice recorders (and virtually all MP3 players with built-in microphones) record in mono, with sampling rates around 8kHz and heavy data compression. That sad combination produces a dull, fuzzy sound. The DS-2, on the other hand, sports stereo mics and sampling rates up to 44.1kHz, the CD standard. (The higher the sampling rate, the higher the frequencies that can be recorded, resulting in a clearer sound.) The DS-2 does use data compression, but its highest-quality modes use Windows Media Audio (WMA) format, which is widely regarded as sounding better than MP3.

For "note to self" situations, where ideas are more important than audio quality, the DS-2 offers DSS, a data-compression format that's optimized for voice. It can cram an astonishing 22 hours of sound into the unit's 64MB flash memory.

To be clear, the DS-2 is not designed for music recording. It ignores high and low frequencies and seems to squash dynamics. But as you'll hear in a moment, its quality is certainly good enough to capture some audio magic, which you then might layer with fuller-sounding instruments. And it's a big step up from tape and typical voice recorders.

DS-2 Box Contents Shown here in its USB docking station (included), the Olympus DS-2 voice recorder also comes with headphones, a vinyl belt case, a proprietary USB connector cable, file-organizing software, and two AAA batteries. (The review unit included Duracells.)

The Numbers, Please

The DS-2 offers five recording modes: Stereo High Quality (SHQ), Stereo Standard Quality (SSP), Mono High Quality (HQ), Mono Standard Quality (SP), and Mono Long Play (LP). You can pick the recording mode on a per-file basis. Here are some of the important specifications; see the Olympus DS-2 site for the full list.

Recording Format DSS (LP/SP) and WMA (HQ/SSP/SHQ)
Recording Media Built-in 64MB
Recording Time 22 hours, 20 min (LP)
10 hours, 25 min (SP)
4 hours, 20 min (HQ)
2 hours, 10 min (SSP)
1 hour, 5 min (SHQ)
PC Interface Proprietary USB cable/docking station
Display Backlit LCD screen; Rec/Play LED
Buttons Rec, Stop, Rew, Play, FF, Index, Display, Folder/Repeat, Erase, Vol Up/Down; Hold switch
File Organization 5 folders, each capable of storing 199 files
Sampling Rate and Encoding 44.1kHz, 128kbps (SHQ)
44.1kHz, 64kbps (SSP)
44.1kHz, 32kbps (HQ)
12kHz, 13.7kbps (SP)
8kHz, 6.3kbps (LP)
Frequency Response 100Hz-17kHz (SHQ)
100Hz-8kHz (SSP)
100Hz-7kHz (HQ)
200Hz-5kHz (SP)
200Hz-3kHz (LP)
Voice Activated Recording Yes
Speaker 23mm (0.9")
Microphone Jack 3.5mm (1/8"), 2 kOhm
Earphone Jack 3.5mm (1/8") 8 Ohm
Power Supply 2 x 1.5V AAA batteries (included)
Battery Life 18 hours
External Power No (but powered by USB when slaved to computer)
Size

122mm x 37.5mm x 17.5mm
(4.8" x 1.5" x 0.7")

Weight 80g (2.8oz), including batteries
Included Accessories Ear buds, vinyl case, USB docking station, USB cable, 2 AAA batteries, DSS software
Optional Accessories Various mics, foot pedals, and replacement parts; see catalog
Suggested Retail Price $149.99
Level Meters In recording mode, the DS-2 displays level meters, although the only input-level control is a high/low switch for mic sensitivity. The "H" means the mic is in high-sensitivity mode (as opposed to dictation mode). We're also in SHQ mode. Note the clock icon; timer recording is enabled.

Recording

You can choose to store your recordings in one of five "folders" on the DS-2. So instead of having one big bucket of sound bites, you might put your shopping lists in one folder, stereo nature recordings in another, melody and lyric ideas in a third, and so on. (The folders are nameable.) Each recording is stamped with the time and date, and you can name the recordings as well, with titles up to 100 characters long. Entering those characters on the DS-2 itself is tedious; it takes 17 button pushes just to get to the naming screen. But you can easily name the files later when you connect the DS-2 to a computer.

Happily, the important recording and playback functions are right on the surface. I found I could begin recording within a second of yanking the DS-2 out of my pocket. All I had to do was slide the Hold switch to the On position and click the Rec button, like a cowboy drawing a pistol. There is a fraction of a second between the time you click the Rec button and when the DS-2 starts recording, but, as with shutter lag in a digital camera, you learn to anticipate it. I got in the habit of recording a bit of "post-roll" as well, to make sure I didn't truncate the recording too early.

Pressing the Rec button again while recording will pause the recording. You can also set the recorder to pause automatically during sections of silence.

While recording (and during playback), pressing the Index button will insert a marker in the file. You can add up to 16 index points to a file. That can be helpful later when you want to jump to certain parts of a long recording; the Fast Forward and Rewind buttons take you to the next or previous index points until you reach the beginning or end of the file. When you import the files into a computer and open them in the supplied DSS Player editor, the index points show up as red dots.

The DS-2 also has a unique (and somewhat scary) feature that will start and stop recording at the time you set--kind of like an alarm clock that spies on you. You can even set it to record at the same time every day. For poetic justice, I had it record my clock radio one morning. You can also make the DS-2 function as an alarm clock, regaling you with a message you've prerecorded. The speaker is quite clear and intelligible.

Timer Recording Tomorrow morning, this DS-2 will automatically turn itself on and start recording, stopping at the time set in the next screen. Yikes.
Backside, with batteries The "programming" buttons are on the right side of the DS-2, shown here with two AAA batteries for scale. The buttons' low profile makes it a little tricky to use them without looking. Holding the Menu/Set button takes you into menu mode, where there are numerous settings. Note the notch above the hinged battery door; it's for attaching a wrist strap.

Why Not Use an MP3 Player?

Many MP3 players, especially the flash-RAM models, include voice recorders. You can also buy add-on mics for the ubiquitous iPod. I was especially interested in the Creative Labs MuVo Micro N200 (see Figure A), because of Creative's reputation for quality audio and the MuVo's pocket-friendly size. (At just 2.6 x 1.3 inches, it could fit on the blank area underneath the Olympus DS-2's buttons.)

Music playback did indeed sound good on the MuVo, and I even got usable FM reception out of this tiny device, which is about the size of a Hot Wheels toy car. But voice recordings were so muffled (8kHz, mono, IMA-compressed) they sounded like they were made through a wall.

Even getting to voice-recording mode was a pain. Whereas the Olympus could start recording within the time it took me to pull it out of my pocket and aim it, the MuVo required six seconds to boot up, then several more for me to wiggle my way down through the menus and into recording mode. Getting there without looking at the screen would be close to impossible.

MuVo Micro N200

Figure A. The Creative MuVo Micro N200 MP3/WMA player has endless features, including a voice recorder. But actually recording something requires negotiating endless menus with the fiddly little scroll wheel.

Playback

The DS-2 also offers a handy Repeat feature. Say you've recorded some tricky chord progressions or political doubletalk. Just click the Repeat button twice as the recording plays back, and you'll create a loop. With practice, it might be possible to create rhythmic loops; the DS-2 doesn't insert loop markers exactly where you click.

Pressing the Play button while a file is playing will play it back faster or slower--without changing the pitch. You can set the amount of speed change beforehand in a menu, from half to double.

Holding the Display button down while a file plays will toggle through two levels of noise reduction, a surprising bonus on a handheld device. It did a reasonable job diminishing background noise on voices I'd recorded in a drafty lecture hall and a speeding car, but it did more to reduce the annoying extra sound than to bring out hidden detail in the voices.

DSS Player, Main Window In DSS Player (Mac/Win), you can audition your files at different speeds, rename them, add comments, and convert them to uncompressed format for use in other programs. (Click to enlarge.)

Hello, Computer

The DS-2 learns a few new tricks when you connect it to your computer with the supplied USB cable or docking station. On both Mac and PC, it shows up as a removable storage device, so you can drag your recordings in and out manually, or transport other types of files. You can also configure it as a USB microphone or speaker, so you can check your mixes on a 0.9-inch woofer!

I was curious if the docking station was just a simple USB passthrough, since it's so small, so I opened it up. I saw what looked like two tiny diodes and a capacitor, which I suppose protect against reversed polarity, because current does travel on the cable. (You can run the DS-2 from USB even with its batteries out.) So perhaps that points a way to hack up an external power supply for extended recording sessions, although fresh batteries should last as long as the memory on all but the lowest-quality recording modes. Olympus's Japanese site says you can charge the batteries in a similar-looking recorder over USB, but I didn't try it on the DS-2.

Installing the Olympus DSS Player software opens other options, including mass file import and comment-editing. It's a whole lot easier to enter file names on a computer than in Morse code on the DS-2, and you can even beam the titles back to the gadget. An optional foot switch ($59.99) turns the program into a transcribing machine. Unfortunately, there are precious few keyboard shortcuts in the Mac version of the software, and what commands exist are often in unlikely menus.

My biggest software gripe was with the audio-editing window, which was consistently off by a second or more. Because there's no Undo function, it was a drag to make edits, not knowing if I'd have to start over because I'd snipped out the wrong part. One workaround is to export the compressed files as uncompressed AIFFs (or WAVs) and edit them in a real audio editor. Of course, if you wanted to put them back on the DS-2, you'd then have to recompress them. Another workaround would be to use an alternative WMA editor. Windows users have several such programs available, but I'm not aware of any on the Mac. Still, it's a pleasant surprise to get software with this much functionality with a $149 recorder.

DSS Edit Screen The editing window in DSS Player lets you add index points (the red dots), delete sections of audio (the blue-underlined section at the end of this clip will be deleted when Erase is pressed), and insert new audio recordings. Unfortunately, the markers are not very accurate and there's no Undo command.
Mic Closeup Strangely, Olympus mounted the speaker on the back of the recorder, but it's bright-sounding enough that speech is still intelligible from the normal listening position (facing the screen). There's also a headphone jack, of course. When recording, I got the best sound quality by pointing the DS-2 at the sound source like a TV remote control.

Audio Examples

Other Voices

Olympus cites the Sony ICD-ST25 voice recorder as the DS-2's closest competitor, but it's been discontinued. The new Sony ICD-SX25 (Figure B) seems to be a better match anyway. I didn't have a chance to try the SX25, but did note that it has half the DS-2's memory, a smaller display (apparently with no backlight), and no Mac software. The menu-control slider looks reminiscent of the one on the ST25, which several reviewers found hard to use. On the positive side, the Sony sports an external power jack, a full metal case (the DS-2 is mostly plastic), and a slimmer design.

Sony SX25 Voice Recorder

Figure B. Like the Olympus DS-2, the Sony ICD-SX25 voice recorder costs $149, records in stereo, is about 4.75" long, and features USB file backup.

The brand-new Olympus WS-200S is probably the model I'll buy. It's smaller than the DS-2 but features double the memory and a built-in USB plug. (No schlepping a cable around!) Unfortunately, it appears to lack time-stamping and a backlight.

For music-quality (albeit not quite pocket-size) recording on the go, options include MiniDisc recorders such as the Sony Hi-MD series, and professional flash-RAM recorders such as the Edirol R-1 ($439 street) and Marantz PMD660 ($499 street).

Because we haven't yet configured the O'Reilly pop-up media player to work with WMA files, the DS-2's native format, I transcoded all of these demonstration WMAs to MP3s using a brilliant Mac program called EasyWMA. That saved me the step of first converting them to AIFF or WAV. Of course, double-compressing a file will degrade its quality, but the difference was subtle in this case. You can download the original WMA files (2.9MB Zip file) to compare if you'd like.

Test 1: Ambient Vocal (angle and sensitivity). In this first batch of tests, I tried to find the best angle for recording--facing the screen, talking down into the end of the recorder, or talking into the small holes on the back. I was also curious how the mic-sensitivity setting would affect the sound. To gauge the effect of reverberation, I went into a shower stall.

Test 2: Dry Vocal. Here, I repeated the test in a jury-rigged vocal booth: my closet. By pushing the hanging shirts apart, I made an anechoic chamber of sorts.

Test 3: Lecture (various quality settings). The DS-2's High mic sensitivity setting is also labeled "Conference," so I experimented at a public lecture by trying various recording-quality levels. I was also curious how stereo recording would affect intelligibility. I was about 15 feet from the speaker in a low-ceilinged, rectangular room with a noisy ventilation system.

Test 4: Parking Garage Ambience. This was a perfect example of why it's so cool to have a digital recorder in your pocket at all times. I was in an underground parking garage and saw a truck coming down the ramp, so I whipped out the DS-2.

Test 5: Children's Song. My 3-year-old son realized recently that the Alphabet Song and "Twinkle Twinkle Little Star" have the same melody, so he started singing them back to back. Another one of those fleeting moments that would have been lost without a pocket recorder.

Test 6: Outdoor Drummers. At a Japanese cultural festival last weekend, I heard a taiko drumming troupe start to play from across the koi pond. Pulling out the DS-2, I recorded the performance as I walked toward them. The crowd noise is interesting as well.

Conclusions

I'm really impressed with the Olympus DS-2. It's fast, sounds good, and looks great. I wish the buttons were textured differently to make them easier to identify without looking. I also wish the software worked more precisely and had more key commands (and Undo!). The only drawback for me is that the DS-2 is just a tad too big to coexist with the rest of the detritus in my pocket. (Yeah, I know I could wear it on my belt, but that's goofy. Maybe I should switch my wallet to my hip pocket.) Fortunately, Olympus just released a smaller stereo recorder, the WS-200S (see sidebar). Neither model is the exact answer to my greedy sonic quest, but I can't imagine letting more amazing sounds slip by, so one will definitely end up in my pocket soon.

DS-2 as Phone This press shot from Olympus's European site shows why people who saw me use the DS-2 kept mistaking it for a cell phone. It's not the smallest voice recorder on the market, but it does have an elegant look.
Digital Audio Essentials

Related Reading

Digital Audio Essentials
A comprehensive guide to creating, recording, editing, and sharing music and other audio
By Bruce Fries, Marty Fries

David Battino is the audio editor for O’Reilly’s Digital Media site, the co-author of The Art of Digital Music, and on the steering committee for the Interactive Audio Special Interest Group (IASIG). He also writes, publishes, and performs Japanese kamishibai storycards.


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