IRIVER SlimX iMP-550 Personal CD Player

The iRiver SlimX IMP-550 CD Player/FM tuner is iRiver's top of the line portable cd player, and arguably, is the top portable cd player on the market today. Though iRiver might not have the name recognition of brands like Sony, Apple or Creative Labs, they are one of the leading manufacturers of portable audio players, and iRiver has become a brand that frequents the best buy and editor's choice lists at many magazines and web sites. It might be the one brand that's got a word of mouth reputation that approaches the word of mouth reputation of Apple's Ipod's.

The SlimX 550's features and appearance are impressive:

- barely over ?" thick, at 0.53", this player is identical in thickness to a AA battery
- Plays mp3, wma, asf, and music cd's (won't play DRM licensed WMA files from websites like Napster, Walmart, etc).
- Adjustable Skip proctection for music cd's, adjustable with default value of 80 seconds, or an option of 320 seconds, and fixed at 900 seconds (15 minutes!) for mp3 cd's
- Up to 55 hours battery life with external battery pack (lots of qualifiers, keep reading for more detials)
- FM tuner
- Wired backlit remote
- Optical output
- M3U playlists, folders,ID3 tags, displays lyrics...
- Upgradeable firmware
- Rechargeable, user replaceable NiMH batteries

My 15 year old daughter requested a new portable cd player for Christmas last year. She listens at least an hour each day going to school and back, and often at other times, and has been hard on other players. Her last player, a Rio Volt SP100, lasted only a year, including one trip back to the factory for replacement. The second time it failed (the read laser gets hung up a lot, to the point where its not usable), it was out of warranty and we decided to replace it with this model.

Appearances

"In the box" you'll find the SlimX cd player, two stick type NiMH batteries (thin flat and long, similar but thicker than sticks of gum), earbud style headphones and extension cable, a car power adapter and cassette adapter, ac adapter, wired remote, external battery pack, slip case with velcro closure and belt loop, and instruction manual. The first thing you notice is that there are so many pieces included. The second is just how thin and small this cd player is, barely larger in diameter than a cd, and only a half inch thick, weighing only 7.5 ounces w/battery and cd. Then you'll notice how "cool" it looks, solid black in color with silver trim, a design credited to INNO (www.innodesign.com). Controls on the player itself are non existent, only a button to open the lid. Batteries are installed in compartments inside the player under the cd, so there's no openings outside the player. There area a few fittings around the outer edge of the player, inputs for the remote, the power adapter and the optical/line out port (headphones attach to the remote).

All the controls for the player are built into the remote, if you lose it, a new one will cost $35 from iRiver. It appears to be solidly built, and I don't expect it to fail. The remote, also black and silver, is about 1" wide, 2" long, and about ?" think, with a spring loaded clip for attaching it to a pocket, collar or seam on a jacket or shirt. The display, about ?" by 1", contains 4 lines of information, song title, folder being player from, file type (mp3, wma, etc), bit rate, battery meter, volume/eq level meter, and play time. As you might imagine, if your eyes are over 40 years old, you might have trouble reading all this info, the indicators for MP3 and WMA are so small I need a bright light to help determine which is indicated. To the right of the display are two buttons, stop and play/pause, intuitively located. No so intuitive are the rocker switches on the top and bottom edges of the remote to choose songs, adjust volume, choose player mode, and access the many user settings and submenus. It doesn't take too long to get used to these controls, but they are not so intuitive than anyone can just pick it up and adjust the equalizer or access random play mode. There's also a "hold" switch to lock out the controls.

I like the cable design, all cables and connectors appear to be designed to minimize the risk of any damage to the cables, remote, or the SlimX itself. Each cable includes extra support where it ties into connectors. All the connectors are gold plated. The power adapter and remote adapter plugs that connect to the cd play both include two plugs in one connector that fits firmly into the slimX. The connector housing are sturdy and only protrude about ?" from the edge of the SlimX. Cables to the remote and power plug exit tangentially (rather than perpendicular as is the case with most cd players) from the connector, minimizing the chance they'll be broken.

The instruction manual is complete and written in clear English with helpful graphics. Its not arranged as well as I'd like (I'd explain how to install and charge the batteries first rather than on page 34 of the 45 page manual), and there's no index. And this is one manual you'll need to read, this player has more features buried in its menus than you can imagine, features like (among many others)…

- an optional fade in function that gradually increases the player volume when you turn it on or switch from the FM tuner
- two resume modes 1) when you turn the player on it resumes the last song you were playing at the beginning, or 2) it resumes the song at the same point it was at when turned off
- different graphics for volume levels, a bar graph, a wave form display, etc.
- have your name or other text displayed during start up or pauses…
- if you download software from iRiver's website, you can add lyrics to mp3 files, and have the lyrics scroll on the remote's display as the song plays.

Listening to CD's

All these features wouldn't be worth much if the SlimX didn't play tunes well. Other than one dusty and smudged cd this player balked at (which worked after cleaning), its handled the mix of pressed and home recorded audio cd's and cdrw's, as well as all of the mp3 files of varying bit rates that we tried, from 64kbs to 320kbs constant and variable bit rate. Though I've not tried it, the latest beta firmware upgrade (version 1.5) for the SlimX 550 includes support for the Ogg Vorbis files(a open source competitor to mp3 and wma formats that many feel offers better quality) at bit rates from 96-256kbps, though the SlimX message forums have mentioned a couple of problems with playback of some OGG files. The ESP (skip protection) works great, we've only used the default setting of 80 seconds, and I can't find a way to make it skip.

Headphones

The earbuds included with the are good, but not good enough to keep you from considering purchasing a better pair. The headphones provide clean playback even at high volumes, but seem lacking in bass response. The earbuds as good as any earbuds I've heard (not saying too much), but they're still the weak point of this player. I've listened to the player with these headphones and my Koss KSC35's, and the $30 Koss headphones are better.

The CD Player

Key specs for cd playback are good, what you expect from a good digital music player:

-Frequency response 20-20Khz (so you should hear all the highs and lows). With my Koss headphones, the sound is full and clean, matching the price tag of this cd player. With the included earbuds, you won't feel taken, but might miss the bass response on some songs.
-Power to headphones 12mW(L) and 12mW(R) at 16 ohms, 8 mW each channel at 31 ohms. Good numbers that indicate the SlimX should be able to handle most headphones to your satisfaction. With the included head phones or the Koss KSC35's that I also use, max volume is more than loud enough to play in a noisy room, vehicle, or doing yard work with a mower or equipment. Volume settings are from 0-40, with a setting of 15 being adequate for light listening to audio cd's in a quiet room, 25 is comfortably loud, and about 35 can be uncomfortably loud for long periods.

- Signal/Noise ratio, 90db for cd audio and mp3 playback (good numbers for a portable cd players, many less expensive players are rated for 85). I find the sound from the SlimX 550 to be very clean, and I detect no background hiss even in the quiet passages of audio cd's. Sound quality of good quality mp3's is also very good.

FM Tuner
We live in a city with lots of FM stations, and don't have too many problems with reception. The local stations are extremely clear and noise free. I didn't find this tuner to be any better at receiving distant stations than other inexpensive radios that I own. The SlimX offers 20 presets, which are set and accessed with the rocker buttons on the remote. The rocker buttons are also used scan for stations or step through the frequencies.


Battery Life

Normally the SlimX is powered by two 1450 mah NiMH rechargeable batteries. iRiver recommends that you need to charge and discharge a battery a few times before it will reach its maximum capacity. They also state that NiMH batteries are good for 300-500 charges. After about 300 charge/discharge cycles, the batteries still are at their nameplate capacity, but by the 500th cycle, they are down to about 60% of their original capacity. If you just top off your batteries, you'll get correspondingly more cycles, so you don't need to worry about draining the batteries completely before recharging. iRiver does recommend that you completely dishcharge and charge your batteries about once/month. An option in the player's menu choices allows you to do this during a charging cycle, making it easy if you remember. If you use your player enough to require charging 3 times/week, for example, the batteries should last 2-3 years, and are easy to replace, assuming iRiver still sells these one of a kind batteries.

The 550 SlimX also includes a cylinder shaped external battery pack that holds two AA batteries that can be plugged into the SlimX in place of the AC adapter. This battery pack incleases the battery life by 2-3 times (one AA alkaline battery has almost the same capacity as both the rechargeable batteries).

I checked the battery life as I wrote this review, after my daughter had used the SlimX heavily (1-2 hours daily) for over a month. I first let the unit go through a complete discharge/charge cycle. I then selected about 6 music cd's and started playing them. The volume was set at about 50%, comfortable for listening in a quiet environment, and the earbuds that came with the player were used. I was able to play tunes for a solid 6 hours and 50 minutes, before the low battery level alarm sounded, slightly better than the 5-6 hours estimated by iRiver. If I'd also used the external battery pack, with the rechargeables, total play time would have been 15 hours or more. Note that the test I ran were at optimum conditions, if you play louder, switch between songs or use the remote a lot, or move the player around a lot so that the antiskip protection is used more, expect shorter battery life, closer to iRiver's 5-6 hour estimates.

If you're playing mp3 or wma files, play time is much longer, iRiver predicts 20-22 hours using only the internal rechargeables, 50-55 hours if the battery pack is also used. When playing mp3 files, the cd is at a standstill most of the time, the players spins the disc to load tunes into memory, but stops the cd motor most of the time, reducing power needs.

Batteries take 5-6 hours to charge. The monthly charge/discharge cycle takes 10-12 hours.

Support

iRiver support appears to be excellent, though I've not used it much. I emailed iRiver with a question about the controls and received an answer the next day. iRiver's main international site has user forums, firmware upgrades, FAQ's and other information, some of which, but not all, is included on their US site. The manual is good, but an index would be appreciated. The player has a 1 year warranty, accessories have a 90 day warranty.


US Site
http://www.iriveramerica.com/

International Site:
http://www.iriver.com/index.asp