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Review: SliMP3
So what is it? Its a small MP3 player with no internal storage of its own. It has an ethernet port, RCA audio outputs (you'll need an external amp!), and a power plug. It has a really bright little screen for displaying song information and a remote. It's about the size of a car stereo faceplate, but a little thicker.
It doesn't have a fancy plastic box. The backside is simply an exposed circuit board. But thats sorta the idea: this is a toy that can work for users, but is also hugely designed to be a hacker toy.
Configuring the device is easy. The latest version has DHCP, but I tested it on a network that lacked the protocol. I put the IP in of my 'Server' and gave the unit its own IP and I was off and running. The server is a perl program you download from the Slim Devices web site. It supposedly will run on on Linux, Windows, MacOS, FreeBSD, BeOS, and MacOSX. It worked great on my linux box. Trivially easy. This unit was the easiest to set up of any MP3 player I have ever used. Of course, I was already running Linux and had Perl ;)
You can control the SliMP3 with a remote control, but the server optionally can just serve up HTML on a high port number and set your playlists up via an acceptable web interface. And since its perl, its all ready for you to hack yourself. The code itself is fairly legible... there's a mailing list, and it is actively being developed.
The closest competitor to the SliMP3 is the Audiotron. The audiotron is almost the same price, has an optical output, a more developed HTML interface, and is physically a nice stereo component. It is a far more mature product. But the audiotron uses SMB file sharing and controls everything within itself. The SliMP3 uses an open source server program to stream the audio to the player. So the smarts are mostly on the PC. Which of course lends itself to easy hacking.
The interface currently is pretty sparse. Some places display filenames where ID3 tags would be preferred. I was unable to get it to load a 20,000 track playlist. But the server software is under active development, and these things should both be resolved in a not-so-distant release.
There are a variety of cool projects that could conceivably be hacked into this thing. A GTK-Perl interface would be super smooth. Cross-fade functions. Intelligent playlist creation. Tivo style thumbs up-thumbs down track rating for music playback. And this is the first MP3 player I've seen that things like this are possible because the code is right there and ready to rip apart. It's even legible!
If you need a pretty box, or demand optical connections to your reciever, go with the audiotron. If you want something tiny, or just want to hack at your MP3 player stereo component, this is a great way to go.
Building one of your own players:
http://www.pjrc.com/
For $10 you can get PalmAmp software to operate WinAmp/XMMS remotely. Add some extra-long speaker cables, and you've got a more functional version of this for a whole lot less. But this is still pretty cool.
The Apple iPod is:
- Height: 4.02 inches (102 mm)
- Width: 2.43 inches (61.8 mm)
- Depth: 0.78 inches (19.9 mm)
- Weight: 6.5 ounces (185 g)
Has 5 gigs of storage (4.66 formated). Thats alot of memory plus it has 20 minute skip protection. The case is also pretty strong, I just dropped mine on to a NYC street from 3 feet with only minor cosmetic damage and major heart skippping.Strange women lying in ponds distributing swords is no basis for a system of government.
The web feature allows you to control the device from _any_ computer (it's a web server), to easily build playlists and similar, and to provide functionality comparable to similar devices. You don't have to use it. It's just a nicety.
The SliMP3 will also play audio streams (Live365, Shout/Icecast, etc.) as well as locally-stored MP3s.
Does it do something more than my computer? You bet. It lets me listen to all my MP3s, playlists, and streams in my living room on my $5,000 stereo, rather than in my home office on my $200 speakers. I even use it via 802.11b, so there's really no problem with wiring.
.@.
wouldn't it be cheaper to just run audio cable
1. Audio cable runs can only be so long with out degradation of signal. Cat5 has longer run length.
Why not use WinAmp
2. Web interface. Is there client control for WinAmp?
3. The device has an IR remote. Much better than running upstairs (or downstairs) to switch tracks on a server in another room.
4.It is designed as an audio component. It can sit with the rest of your stereo. And can be operated as such by people that don't need to be messing around on your computer.
5. It can serve mulitple devices. You can serve your 80GB audio collection throughout the house to multiple locations. It is much more difficult to split line level audio output across 4 locations.
______
Once: you're a philosopher. Twice: a pervert.
Just over one year ago, Rob posted a story about my little Open-Source MP3 Player Project... which also isn't the first open-source design (but it may be the first open-source player that you can buy the hardware instead of buying all the individual chips and soldering them yourself).
Well, enough shameless self promotion for one day....
PJRC: Electronic Projects, 8051 Microcontroller Tools
You could always hook this thing directly into a WAP, and then bridge that to the WAP at your PC. I know its not the cheapest or easiest way to do it, but it *would* work.
$250+ for an MP3 player that doesn't have it's own storage with a display that doesn't exactly look as professional as other MP3 players on the market...
Umm... not storing the files on the player is the whole point! The idea is that you can have two or three of these in different rooms of your home, and they can all be controlled idependently, with your music all stored in one place. So the amount of music you can access is not limited by the player, and you don't have to replicate your collection between several hard disks.
The display is vacuum fluorescent, as opposed to LCD. They're much more expensive than LCDs, and much more readable. I had trouble taking a good photo of it though - you really need to see it in person.
I chose to go with the VFD because even though it's expensive, the $30 price difference vs. the LCD is not a huge percentage of our cost right now. Some day, we'll might make a cheaper version with a backlit LCD. Right now it doesn't make much sense cost-wise, and people generally feel that the VFD is worth the $$.
And it's not even availiable yet! I wonder how CmdrTaco got his. A "free" review copy perhaps?
Yep, I sent him a prototype so he could write the review. The product will be available for sale in 1-2 weeks.
Sean
As another poster has pointed out, the hum you experience is known as a ground loop.
;)
The vast majority of ground loops (~95%) in homes are due to improperly-grounded telephone, cable, and satellite systems. The rest are due to dangerously broken equipment.
Here's what happens:
Cable/phone/sat guy shows up to wire a house. The existing ground rod is inconvenient for him to tie onto, so he drives his own in a more convenient spot, and uses that to connect the shield of the coax to earth. This is usually illegal, per National Electric Code, not to mention a Bad Thing To Do.
So. You connect this to your TV, and your VCR, and whatever else you have - and that to your stereo. No problem, because these components typically do not have a connection to earth (ie, they use 2-prong power connectors) - there is only one path to ground, and no hum occurs.
That is, there's no hum until you plug in your grounded, 3-prong-having PC to the mess. After that, you've got two paths to ground from the stereo - one, via the cable TV wire, and another through the audio cable, sound card, PC chassis, and electrical outlet.
More often than not, there is voltage potential between these two grounding points. By tieing them together with a patch cord, current flows. This gets amplfied, and delivered to the speakers
as familiar 60-cycle hum.
So. How to fix? Just identify and remove or isolate the offending ground. Leaving your computer plugged in (and humming) start pulling wires off of the stereo, unplug your modem, and so on until you identify the source of the problem and achieve silence.
If I recall, the NEC specifies that ground rods need to be driven 6 feet into moist earth, and that if more than one is used for a given structure, that they must be connected together using #6 wire, with additional rods also driven 6 feet into the ground at 6 foot intervals along the run. It's expensive, and laborious.
That said, it's better/cheaper/easier to remove/disconnect the offending rod, and run a wire to the main (electrical) ground. Simple enough, and should be able to be done in less than an hour in all but the most extreme cases. Also complies with NEC.
But, you're not allowed to touch the cable company's wiring, as it doesn't belong to you. Which means that they'll need to come out and fix it themselves - which is great, if they're willing to even acknowledge that it's their problem, because they also have to do it for free, just like any other problem that happens on their side of the demarc box.
In the likely event that they're not so cooperative...
Use a pair of real transformers (the Radio Shack 75300 ohm jobbie made for outdoor antennas works, and is probably the most readily availalble) back-to-back (that is, connect the 300 ohm twinlead ends of them together) to "fix" it.
All this does is isolate the ground. You can insert your newly created device any point on your cable TV wiring that falls before your stereo -- the further upstream, the better. Bonus points if you connect your ground-isolated coax to the proper grounding rod with heavy-guage wire - it's good for signal quality, and helps keep stuff from leaking. Done right, no ground loops will be introduced.
For troublesome telephone and satellite systems, there is no plug-and-play Radio Shack solution. The FCC says you're not allowed to have a transformer on your phone line. Also, both satellite and telephones need DC voltage to operate - which the transformer would block. You'll have to remove their existing ground connection, and tie them onto the building's main (and now, only) ground. Same no-touch rule about phones, though - they own that end of it, too. Good thing that the phone line is almost never the culprit, due to the way things interface with it.
And you should own all of your satellite gear, since the demise of Primestar - you're (thankfully) on your own if that's the problem.
Oh. Lest I forget: Don't just clip or otherwise disconnect the ground wires. Same goes for 3-prong "adapters", or 3-to-2s. Bad news. Ground connections are there to prevent you from killing yourself, to keep your cable system from leaking, to shield your PC, and prevent static discharge into your AV system from your fiberglass satellite dish, as well as lightning protection for phone and cable networks, and surge protection on PCs.
Copper isn't cheap, and they wouldn't throw in extra wires without a damn good reason.
Kid-proof tablet..
The point of this device is to have the ability to play digital music on your AV equipment which is generally located in another room. In my house the living room is at the opposite end and one floor down from where my boxen reside. If I wanted to change a track using an audio cable solution, I would have to get up and go upstairs. This device allows users to do that from the comfort of their sofa. I don't want to stick an ugly beige box in my living room. This device and others like provide a lot more functionality than your solution. And no, an RF remote for a PC would also not work because you wouldn't be able to display the tracks.