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Hardware Streaming MP3 Components?
woogie asks: "I have finally broken down and ripped all my CDs, and I have a mod_mp3 server with a bunch of different streams based on genres that can deliver those mp3s to anywhere in my house. Anywhere, that is, except my stereo system. Anyone know of decent audio hardware that will read a Shoutcast stream? Sure, I can plug my laptop line out into my tuner's inputs, but I'd really like a device I can just stack on top of my tuner that will accept Shoutcast streams. The only device I've seen that allows this is the Audiotron which appears to want to read your mp3s from an SMB share, but can be configured to read Shoutcast streams if you use special Windows based software to configure it. It would work, but seems a bit pricey given that it targets my needs as an afterthought. There is some promising hacking going on with the Rio Receiver here and here, but getting one to read a Shoutcast stream might be beyond my abilities. Am I missing anything else out there? A simple device that I could just cycle through different preconfigured streams with a remote would suffice."
if using a remote is the bulk of the functionality you want, then don't overlook using an old laptop. X10's universal remote ($25 US) has a serial-port receiver and works great for controlling winamp. (there's a few plugins that give you winamp functinoality) .
the other good thing about that setup is that the X10 remote uses RF for the computer control instead of infrared... so line-of-sight doesn't matter.
Somewhere on this page I have hidden my signature.
You have to use Turtle Radio (http://www.turtleradio.com/) to configure which shoutcast/icecast streams the Audiotron knows about, but you can add in all your own stations. The Audiotron just downloads its station list when you power it on (or tell it to update). Turtle Radio is free, you just have to register to get the ID code that your Audiotron will use to talk to it.
Incidentally, the Audiotron is a great piece of hardware. The interface is well designed (as of 2.0, anyhow), it works really well, and the support is phenomenal. Voyetra/Turtle Beach pays a lot of attention to its user mailing list, and has implemented basically every feature that folks on the Audiotron mailing list have asked for. I bought mine a year ago, and haven't regretted it for a second.
One of the things that makes the PC so powerful is the ability to add "dumb" peripherals that add major functionality by leveraging the generality of the PC.
/dev (maybe /dev/hi-fi?) device, rather than having to address it by IP.
/dev/dsp for "main system sounds." Allowing high quality, hack-free use of the stereo for general PC audio.
/removed/.
In this vein, why not have a simple peripheral that:
1. Gets power from ethernet
2. Talks IP or some simpler protocol
3. Has a DAC that is able to convert one uncompressed digital format (say, 44.1kHz PCM) to high quality stereo analog.
4. Optionally has an IR or RF remote that sends simple events back to the PC.
Here is the real beauty, especially on a UNIX system: adding codecs is trivial. Really adding any functionality is trivial. Want a random mode, code it up. Need more space, add it to the PC, want to be able to play all songs that match a regexp, code it up. The real slick thing would be that it could play audio that was encoded in a way never even dreamed of by the hardware OR the software designers through UNIX pipes. There could also be a driver that allows it to appear as a simple
I suspect that any 2nd year EE student could design and build this thing with a DAC scavenged out of a CD player that suffered mechanical failure.
You could even use this to replace
Some ideas about obvious problems:
1. Give them all the same MAC, but make the last byte configurable by dip switches (to allow multiple devices on the same ethernet segment). All config could then be handled automagically by the driver.
2. Design it to take power from ethernet OR an A/C adapter.
3. It will need some buffer. A few megs should be overkill.
4. In case this isn't clear, it would be a totally "push" device. It would sit there and just dump whatever came over the wire with its IP/MAC into a buffer, which dumps right into the DAC.
Advantages:
1. Never fight with Linux sound drivers again.
2. All DA conversions prior to the box itself are in software, and therefore don't pick up "chassis noise" like a soundcard does.
3. "infinite" upgradeability through PC software.
4. Total platform independence. If it talks ethernet (and IP?), it can control the device.
5. "Patent-proof" I am pretty sure you can't patent something that is just like something else, only with components
The only real question in my mind is wether it is worth it to implement IP on the thing, or if it would be better to just use a very simple, non-routeable protocol on top of ethernet.
Does anyone know of anything like this? By like this I mean something that is simply a DAC with ethernet. There a a bunch of devices out there that decode MP3s, etc. That's not what I am looking for.
Any EEs out there want to take a whack at it?
And, to come back around to being on topic, he would be able to "play" his shoutcast stream locally, and push it out to his stereo with this thing, if it existed.
-Peter
I'm extremely lost to what you're talking about. If you're talking about a standalone unit, then why do you bring up UNIX and PC upgradability?
Oh wait a second. You're saying, basically, create a sound card that uses ethernet instead of PCI/ISA. Man, if only infiniband was available now.
There are quite a few DSPs available that would do something along these lines. You have peaked my interested. You'd basically need a DSP w/ ethernet and then a small external amplifier. You could probably through a 1M SRAM on the board. Use DIP switches to set the IP address, etc, etc, etc. But in the end, you would basically use the PC (and I'm only thinking about XMMS) to decode the MP3s and instead of sending "audio content" to the sound system, it sends it out via ethernet. I wonder if ESD could be adapted to do that even. Hmmmmm....
Damn dude, I've been CRAWLING for a hardware project (I work for a test and measurement company, and I have all this nice equipment with nothing fun to do). Hmmmm.
A sound card that uses ethernet instead of pci/isa, what a great way to say this in less than 80 words!
/dev/hi-fi" None of this wait for the vendor/flash the device/give up on the vendor and rip out the OS and put in Linux crap.
The reason I bring up UNIX is that adding a codec would be as simple as "$ foo_codec_play some_song.foo >
Seriously, if you skip the remote and just use raw ethernet frames I think this could be done with no brains at all in the "ethernet based soundcard".
I don't know what "infiniband" is, but as I figure it a 1x cdrom (which is where the 44.1kHz PCM thing came from) xfers at 150kB/s and 10meg ethernet is 1280kB/s ((10mb) * (1024k/m) / (8b/B)). So this thing would use 12% of 10meg and 1.2% of 100meg ethernet, not accounting for overhead.
I'd prefer setting the MAC by dips. Then if it does us IP, just set up MAC affinity in DHCP. Anyway, like I said, the driver could handle all this. The more I think about it the more I think IP is overkill. Being limited to being on the same ethernet segment as the device is not a big limit. And you could always add a proxy system (if you want to play on a device on a seperate segment you proxy through a machine on the same segment as the device). Again, make the hardware dumb and the software smart.
Oh, and I updated my email address. Please mail me if you want to persue this. I'll buy all the parts if you build two!
-Peter