- or preliminary review
I have been working with a student on a project that is putting various hard disk digital music players through their paces. There is some need for this as most of the reviewers quote manufacturer's published numbers and say "wow - 0.1% thd ... the sound quality is great..." They probably don't realize that published numbers generally are fairly meaningless.
To date a few CD players (ranging from $200 to $4000) were tested as references with 16 bit source material. Two iPods (a first generation 5GB and third generation 20GB) and a Dell DJ 20 have been through the rings.
The caveat is that one must consider many variables when selecting a player. In addition to reproduction quality one generally worries about
price size battery life user interface earphone quality supported formats other features - fm radio, recording capability, etc style hype from ads, media and friends
Some of these may be more important than audio quality. Many people use players with 128 kbps mp3 files and stock earphones (the earphones on every commercial player I have used are not very good) - a low quality player may be as good as one with much better electronics in this case. The same can be said about interface. For me this is a "make or break" item - other people just get used to a poor interface and go on with their lives.
So with that here are some audio tests.
We have access to a Miller Audio Research QC Suite, a variety of Tektronics and HP (when HP instrumentation was HP:-) spectrum analyzers and reference quality speakers, headphones and earphones. Listening with a human was ruled out as testing is difficult and expensive - so any comments on the quality of the music through transducers to human ears is very subjective.
The tests are straightforward and similar to those benchmark tests for digital audio equipment:
frequency response channel separation 1/3 octave spectrum of 1 KHz dithered tone at -90dBFS right and left channel non-linearity 500 Hz, 1KHz, 2KHz and 2.8 KHz sine spectrums (injected tones are .wav files) IM distortion hum a few others that look at the DAC -- jitter spectrum for example
At this point I note both of the iPods are surprisingly good - comparing with dedicated CD players in the $500 range.
The numbers I will quote at this point are those that don't require plots (which need to be printed in the context of the full text) .. For the sinewave spectrum tests the we find the worst iPod (they were within 2 dB of each other at all points) harmonics were the 2nd and 3rd (-63 and -73 dB respectively at 1KHz) with all other harmonics below -92dB. The Dell DJ 20 had noticeable 2nd, 3rd and 4th harmonics (-56, -67 and -68 dB at 1 KHz). I mention this test as this is one you will hear if you have good ears and earphones and a good music source.
The noise floor below 1 KHz on the iPod and DJ is probably analog from the output circuitry and is 10 dB worse on the DJ.
The tests suggest that the DJ uses a lower quality DAC/amplifer than the iPod. This isn't surprising as it gets much better battery life than the iPod at similar output settings ...
The results of several players will be finished by the end of the semester and will be published (hopefully) in the late Winter or early Spring.
_____
I wanted to mention this to note that there are differences in players that go beyond printed specs. I require good enough audio quality. I am willing to compromise and use compressed music. For my ears 160 kbps MPEG-2 AAC is good enough (even on a good stereo with great headphones) - any of the other codecs below 200 kbps aren't good enough (mp3 is laced with artifacts - once you know where to look it is annoying to listen to mp3).
The Dell DJ does not support AAC and, even if I used Windows, it wouldn't make sense as dealing with 1000+ CD libraries still requires compression at this point (at least for me). Not to mention that I have already compressed my library in 160 kbps AAC.
Battery life is clearly better on the DJ (the owner quotes he regularly gets 12 - 16 hours on a charge) than the iPods (7 to 10 hours), but I am willing to trade what for me is good enough playtime for better audio quality and AAC support.
The other differences are difficult to quantify and, as a long-time iPod user, I have some bias. The DJ felt somewhat cheap and its thumb wheel did not have a good feel. My friend notes the feel varies from unit to unit. I prefer the physical design of the iPod, but that is completely personal (it is also probably as important as price for many people).
So there you have it. If you are a Windows user and don't want to invest in better earphones and/or have a huge library of mp3s and find the sound quality OK I would go for it. If you want to use a higher quality codec and worry about sound quality enough to buy better earphones I would spring for an iPod at this point - refurbished iPods cost about the same as a new DJ and have similar warranties. If interface is an issue I would borrow players from people and spend at least an hour with each.
Finally I note that the DJ owner loves his player - he is thrilled with the long play times and has a large library of mp3 files that are good enough for his ears. He is happy with the stock headphones. If this represents the average consumer, Dell may have a great selling unit on their hands.
My parents are getting me a DJ and I'm psyched. I'm getting the 20 and need all the space cuz I want the mp3s on my friends computers We have AOL and my dad watches what I do online so I can't kaaza the mp3s I need. This is better than getting cds burned.
dumb review I gues u R a mac lover.
Posted by: josh | November 27, 2003 at 14:47
Stereophile Magazine seems to agree with you on the iPod. These are the guys who spend thousands of bucks on gear and they named the iPod the editor's choice and the budget product of the year.
I just bought a 10 GB third generation iPod and am saving my change for some Etymotic ER-6 earphones. Maybe my girlfriend will get me a pair for Christmas.
Posted by: thom | November 27, 2003 at 15:19
a postscript ...
It is astonishing to perform actual measurements on some of these devices. I haven't mentioned all that have been tested as the tests are still incomplete, but some of these devices have DACs and amplifiers that are beneath what you see in some $50 portable CD players.
It is equally astonishing to realize how hap-hazard most reviews are. Technical numbers are taken from spec pages and someone who has no idea what a Fourier Transform is writes about distortion and sound quality. Very few places take the time to do technical reviews or serious user reviews.
Build quality and user interface design are also all over the board. Over the years I have come to really hate bad UI design (try out a BMW 745 to witness some of the worst you will encounter) and some of these players are just awful. The Dell is reasonably good, but it is not an iPod ... will that matter to most people? ... probably not.
The iPod is remarkable for several reasons ... it pioneered a design more than two years ago and still has not been equaled. Most surprising is how good the design is under the hood. The group that did this one was working under the influence of passion. Often passion for design is not rewarded in the marketplace, but so far Apple seems to be doing well with this one.
Posted by: steve | November 27, 2003 at 15:34
I think the iPod has made the leap into being a fashion accessory. Many of the people around Boston don't care what it plays or how well it plays it as long as it is an iPod. Witness iPod ads in fashion magazines this month.
The other group of people who buy these boxes are using them to share mp3s. It is much easier to walk up to someone's machine with a portable hard disk than it is to burn discs. Most of these people seem to be teenage boys and I don't think they worry about style and other things. I would expect them to go after the cheapest unit with the largest disk.
I haven't used a DJ, but don't think it addresses either market. It seems to be going after the joe and jane knock-off market that Wal-Mart serves. Their biggest competition would be a Wal-Mart player.
Posted by: cindy | November 28, 2003 at 09:05
I have a sudden need to have a mp3 player like the Dell or iPod and came across your page in a search. Right now I'm set on an iPod. I don't make a lot of money. My car is seven years old and I'm still paying off college loans. On the other hand this is an affordable luxury as opposed to an unreachable one. I'll forego a new coat and a few other things this year and will probably be happy.
My boyfriend's Dell burned out on Thanksgiving and he has been going through hell trying to get help from their support people. That has pretty much turned me off to the DJ -- on Wednesday I almost pressed the buy button on their webpage. Now I'm probably going for the iPod.
Thanks for your article. This has helped me even if I didn't understand most of it.
Posted by: marsha | November 28, 2003 at 20:33
Here is my update. Last night I went to the Apple Store in Walnut Creek and bought the 20 GB model. They had a 10% sale making the pain a little less, but it is exactly what I really wanted.
I have about 200 CDs, so there is alot of room left.
Now my problem is I played with an iBook. My PC is a 3 year old Gateway with a burned out screen. I have to use it with a monitor. I was planning on getting myself a Dell after Christmas if there are any sales, but the iBook was very sexy.
My boyfriend's Dell was his laptop. I reread it and it looks like he may have had a DJ. The machine that burned out was his Dell desktop. It is only a year and a half old and he is really pissed at Dell.
Posted by: marsha | November 29, 2003 at 13:42
I have a DJ 15 and really like it. The earphones are pretty bad and I spent $40 for some Sonys, but it sounds pretty good now. The software it comes with is pretty bad though. I'm not bothering with their music store because I got this to share music with my friends PCs. It works pretty well for that. I already have 7 G of mp3s on it. This is a whole lot better than burning CDs. We don't have a cable modem because my parents like AOL so I cna't use kaaza.
My mom told me she would get me this if I didn;t download music, I sort of foxed her.
Posted by: joel | November 30, 2003 at 09:19
Joel, you are a real cool dude, you out-foxed your Mom. Wow, you're neat.
Posted by: baukunst | December 01, 2003 at 08:45
I have one and like it.
The big plus is the battery life. Minor annoyances are the scrollwheel and not hearing music when you scan. Major annoyances are the shit earphones and MusicMatch software. If you get one get some real earphones and better jukebox software. There are a lot of choices out there.
The Dell isn't an iPod and that's why I like it. I didn't try their online music store and don't really care. I'm not going to do copyprotected anything.
Posted by: Seth | December 10, 2003 at 06:01
With my birthday and Chanukah money I have $300. My friend Sarah got an iPod and it is just what I want. I went to the AppleStore in Palo Alto yesterday and they were out of the $300 iPods. I was looking for information on the Dell so I could get something but I haven't seen one and people who compare them like the iPod better.
Someone at the AppleStore told me that Apple may come out with something new in January and that I should wait until then.
I want one of the little silver Apple laptops. They are beautiful. My Dad said I can have one if I can pull my grade point average to 3.5.
Posted by: Hannah | December 21, 2003 at 11:25
postscript to a postscript
A note from the student I've been testing players with ... His Dell seized up with nasty hard disk noises about a week ago. This is going to be true with any new electronics and this will give him an opportunity to report on service.
In the past the only music players I've had experience with service-wise were two Rios ... both were awful (in construction as well as well as support from the company. one of them was in "the shop" for over three months and they sent a bad unit back. Under some pressure they agreed to sell me a Rio 800 for the difference in list prices. It was a turkey too)
I can't report on my iPod other than noting it has just worked for over two years. The battery only has about 70% original capacity, but that is normal for a Lithium-Ion polymer battery. I'm going to have to replace it one of these days.
Posted by: steve | December 21, 2003 at 16:01
i have the dj.. as for software i do not use musicmatch for transfering files .. the best software out there by far would be dudebox... www.redchairsoftware.com/dudebox .. it integrates with windows explorer, its extremely easy to use, and it allows users to copy there music from their dj to their computer (the feature was supposedly disabled by dell to prevent sharing music illegaly, but this software enables it)
if you have the dj i would definately get this software.. there is a free version but i suggest the full version (one time- $25)... it makes the dj so much better
Posted by: Joe | December 24, 2003 at 10:38
Joe is completely right. Musicmatch bites. Dudebox is the only way to go with the DJ. The full version is worth the money.
You also need better headphones so save some money for something better. I got Futuresonic EM2 for about $160. It makes the DJ sound wonderful
Posted by: Tom R | December 25, 2003 at 16:25
I found this page a few weeks ago and got an idea for a science fair project. I'm testing mp3 players.
Our high school physics lab has a HP Spectrum Analyzer that is about 15 years old, but is very nice and some other audio test equipment. I can't figure out some of the tests you are doing, but am trying to duplicate what the stereo magazines do as much as I can.
My friends have three different hard disk players and I'm learning how to run the tests with them and my iPod. I'm hoping that I can test more types and the solid state mp3 players after Christmas. The science fair is in late February.
Posted by: Justin L | December 28, 2003 at 06:42
Don't get a Dell. I got one for Christmas and it quite playing yesterday. The it is making clicking noises and the sound just quits. I've spent an hour on the phone trying to figure out how to get it exchanged.
It isn't very friendly to use. I really wanted it and begged for it for Christmas, but it isn't very good.
Posted by: karen | January 07, 2004 at 22:55
OK I was looking to see if you can use DJs with Apple's music player. My sister has it on her HP computer and it is sooooo much better than what came with the Dell. I'm beginning to think that my Dell DJ isn't what I wanted.
It works OK, but you need to replace the headphones. Getting the software to work on my Dell laptop was a major problem with two hours of phone calls to Dell.
What really rubs the salt in is the Dell isn't cool. People ask me why I didn't get a iPod. I find myself appologizing for it.
Posted by: Jenny | January 08, 2004 at 22:37
Is anyone buying Dell DJs? I want to look at all of the players, but all we have around here are the really cheap and tiny players and iPods. The iPods seem great, but you just don't see people using anything else. How can Dell sell so many PCs and so few mp3 players? Is something wrong with them?
Posted by: Alex | January 12, 2004 at 06:30
I came here from a page where someone didn't get the point that efficient amplifiers tend to sound worse than inefficient amplifiers. This isn't universally true, but the specs on some of the high efficiency amps (used in some of the longer playing players like the Dell DJ) are seriously worse than less efficient models used in other players.
An amp isn't an amp and any piece of engineering is a compromise. Apple seems to have chosen a part that sounds better. The author knows what he is talking about.
Stereophile did a great review on the iPod recently and came to a similar conclusion.
Posted by: alan | January 14, 2004 at 08:00
My DJ works OK I guess. You have to get a better jukebox for your PC because what they give you is lame. There musicstore is even lamer. I guess what bothers me is the DJ just isn't cool. It is like spending tons of money on the wrong label. Maybe it is OK for old folks, but I'm not happy with it.
Posted by: Jessi | January 15, 2004 at 14:54
I like my DJ. I traded my PS2 and some games for it and got a good deal.
The headphones suck and you need to get better. I got some Sonys for $35 at BestBuy that have loud bass.
The software doesn't work. I use Lame to make my mp3s and Dudebox to store them. Dudebox is great.
The Dell and Napster musicstores suck. Your better off trading mp3s with friends. I don't want them knowing what ive got besides.
Posted by: F451 | January 18, 2004 at 11:30