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Build a Multi-Output MP3 Server?
z80 asks: "I'm rebuilding my house and I am thinking about fitting speakers in every room of the house and pulling some massive amount of cables in the walls. I also want to control and send the output to each set of speakers from the same source, and was thinking that a PC, with 4-6 soundcards, would do the trick, and there are of course a couple of questions I have. What kind of hardware would be required to be able to stream up to six different MP3's through six soundcards at the same time ? Can it even be done? What kind of software can be used to do it? Which OS? How can it be remotely controlled? With respect to the last question, I'm thinking about mounting a couple of flat displays around the house connected to old PC's that run some sort of connection (VNC maybe) to the mp3 server." This is a topic Ask Slashdot tackled three years ago. Now, with applications like Ardour showing off the power of Open Source frameworks like JACK, it seems like building such a machine might not be as hard as it once was. For those of you who have managed to build something like this, what did you do and what hurdles did you have to navigate before things were working? How would you set up a machine to run independent audio to 4 or more rooms?
The best place for questions like this is the AV Science Forum. Lots of people doing all sorts of home-theater/home-audio projects. Look in the "Home Theater Computers" section.
There are several options for what you're looking to do these days. My brother is doing a similar thing, but he's using 802.11b for control (through Girder) and PocketPCs for remotes!
http://www.avsforum.com/avs-vb/
you could network tablet PC's to it and use wireless speakers, that would work
Hahaha you asked 'Which OS?' on /. I guess you weren't looking for an unbiased opinion :P
I got a +5, Troll
Get an M-Audio Delta 410.
It has 4 inputs, and 10 outputs.
Common sense is not so common.
I thought it would be great to have multiple outputs on soundcards. Why have 4-5 cards when you can easily have a pigtail with RCA connectors (or 1/8 connectors). It should be possible and would solve those issues. Imagine playing a DVD on your TV while someone else listens to MP3's
:)
Software wise, it shouldn't be harder than controling multiple NIC's. Soundcards could be seen as "streams" and you could send the audio to any/all. Heck you could even have some kind of multicast to remind everyone of special events (blue light special? err.. dinner is ready).
Unfortunately, the company I contacted couldn't care less about my idea.... Or maybe they simply took it and are working on it now?
-- Leeeter than leet
One of the side effects of not having commercial drivers and applications that use the features is that you can usually get at least two channels off of a 5.1 soundcard. The front pair of speakers and the rear pair of speakers are generally treated as seperate DSPs by the audio driver. Look around for audio drivers that treat the cards this way, and when you find one get 3 cards for a total of 6 outputs. (You're looking for a card thats supported in linux, but not too-well supported. Don't forget to check alsa's list of cards)
After that, just figure out how you're going to get the controls to work.
If I have been able to see further than others, it is because I bought a pair of binoculars.
what did you do and what hurdles did you have to navigate before things were working?
My Wife.
I know people don't read the articles anymore before posting, but please at least read the post.
It clearly says that he wants different streams, not the same stream lots of places.
You could use ATI Remote Wonders (or, perhaps, a similar kind of X10 remote).
These are RF remotes and 16 of them can be configured to use different channels. They use USB dongle for reception - same dongle can serve multiple remotes if needed (just don't transmit simultaneously).
Linux driver can be found at GATOS website
If you're going the "old PCs" route for control, forget about distributing the audio. Too much work. Just run a network cable to every room (or go wireless) and use old PC's as clients/players of shared files stored on a central server.
This would work TODAY - you wouldn't have to do any customization of software or hardware.
AudioPCI cards are cheap but great sound for the bucks.
In my mind the only downfall is the noise from a PC unless you go to lengths to silence them, eg put into closets.
While the idea of using several soundcards and OSS is quite sound, this is a problem which has already been solved by professional audio installers several times over, with equipment custom-tailored for this exact purpose. IMHO, you should get a professional consultation from a home theatre/automation business. The difficulty is not the soundcards or even the software, it's integrating functional control panels (with displays) into each room that will prove to be the most difficult. While you certainly *can* do this with off-the-shelf parts, the pros will always do this sort of thing better.
Good luck!
How much distance can you run with your audio cables before you start to get significant loss of quality?
I agree with the others, who have said, if you are going to include an LCD in some of the rooms, what's the problem with adding a very small PC? You could even do a wireless network, and have the terminals access the files.
As I don't really know of anyway in which you can get five soundcards, to all function seperately, and have independant players associated with each card. I think that having a large storage server, and then some small terminals controlling smaller areas of the house, will be easier, and less of a logistical nightmare.
I would say get a bunch of via epia mini-itx mainboards (newegg sells them with some pretty slick cases as well). Just run Cat5 to each room and viola! you have a multipurpose device, you could watch a DVD (or at least a visualization) with your music as well.
Besides, the EPIA boards are quite well supported under linux (and of course windows), heck you could even network boot them so you have diskless stations - now that would be killer. Absolutely no moving parts, you could just stick the board to back of the flat panel and mount it in the wall.
A computer with a ton of sound cards seems like a great project, but I can tell you right now it is much more prudent to be running cat5 to each station and having separate little boxes...
Bad idea. It's MP3... just put an MP3 player in the room and use network cable. You can buy an old Vectra (that would do this fine) for like $50. Or you can use dedicated audio widgets like the very open mp3elf.
Who are you kidding? you're on a linux site, you're just trolling for some karma/recognition.
I'll answer all of your questions, even though I know it's not the answers you want to hear:
My winamp uses up 2 percent of CPU on a dual 450 PIII with a memory footprint of 8 megs. That means you could have say, 50 different streams with my system. Or get 6 streams with about 100 Mhz chip (to be conservative). A low end PIII will do the job is your answer.
it can be remotely controlled via many things, IR ports, LCDs with touch screens, your cell phone, a wireless PDA... your imagination is the limit.
and the kicker: Windows NT/2k/XP can handle it. Just like any other of the current OSs would. You just launch as many winamps as you want, configure them to use a specific sound card, and voila.
*yawn*
Most command-line MP3 players (mpg123, for example) have options to specify the sound device. This would allow you to control which room the music was sent to.
CPU-wise, decoding a bunch of MP3s should be no problem at all; mpg123 typically uses only 1-2% CPU on a modern machine. I don't think you'll run into PCI bandwidth limits either (guestimate 1.4 megabits per second per output).
You may need to create your own player front-end, to select songs/playlists for each room.
or does anyone else find it strange that sometimes Slashdot editors remember a story being posted 3 years ago, yet other times post the same story twice (or more) in a single day!?!?
The Ethernut is more for a doityourselfer, the Slimp3 is existing product. They operate over ethernet which is not quite within scope for the abovementioned project, but might meet the same goals.
I haven't gotten around to either of these yet, but the Slimp3 in particular sounds quite cool.
-jbn
I made a an XMMS console remote and ran it from my zaurus over wifi. I know use a dedicated MP3 server that mounts my music over samba and lives inside my stereo.
The script could easily be adapted for use in almost any control environment. Up/down+enter for easy use on the Zaurus w/out typing.
You can't judge a book by the way it wears its hair.
Yeah, you may be able to hack something together with a single PC and multiple sound cards in a few months of Sundays. But you could also just buy, off-the-shelf, as many of these dandy little things as you need. A single server can service as many of them as you'd care to stack up. They would be easy to add on as you require them, without having to run any speaker cable at all--a wireless bridge or a single CAT5 run works peachy. DHCP enabled, supports multiple server OSs (mine is off my Debian box but they have Windows or Mac installers as well), wireless remote, Web, or command line interfaces all supported.
I've only got one, but it works awesome and if I ever decide I want to put a different sound system into another room, I can just buy another module and hook it up to the same server--instant access to all the MP3s and playlists that I've already created. The sound quality is great and it take hardly any resources, either server-side or network. I highly recommend it.
No relation to Happy Monkey
So by the time you have the requisite NIC, your video card (PCI or AGP), you are left with 3-5 slots left for audio cards.
Then you have issues with the bus bandwidth and that many audio cards.
People have mentioned using 3 card and use the front/rear outputs for different streams, but the cards don't work that way (or at least not without at LOT of driver coding, and no way you can easily get your audio player to recognise this)
There are several solutions to this:
Good Luck
RoundTop
Seriously, they call it Bob. It's the ZR8630AV - and he's got a sister named Glory - the ZR4630.
Glory is a 4-source, 6-output, 30 watts per channel audio distribution center. Check out http://www.nilesaudio.com/products/zr4630.html for more information.
We use these a lot where I work now, and they're slicker than snot.
"If there's hope, it lies in the proles..."
cat5 much cheaper..
I wanted to do something similar, but the other direction.
I wanted to have mics around the house in lots of the rooms. I want to be able to walk into the bedrom and say "lights on" and have the computer turn the lights in that room on - I don't wanna have to say "master bedroom lights on".
I really am not sure how this would be done. I'm guessing there would need to be some sort of intermediate box that would pass the audio through, and at the same time be able to indicate to the computer which input it received a signal (or the strongest signal) on.
The concept of multiple people listening to different music all throughout a nice large house is a bit tough to grasp for us basement-dwelling lonely ./ reading geeks. An honest mistake I'm sure.
Anti-social? My code is just platform-specific.
The company I work for: Intellinet Controls sells multi-room audio systems. Our latest product, the RS3000, includes web based control (which is really nice with a wireless webpad), keypads in each room (and a remote), and can be easily intergrated with mp3 jukebox software (I use Globecom Jukebox) (we plan to provide it as a option for those who don't want to set their own up) I have a system installed in my house, and I think it is great (of course, since I wrote most of the software it does exactly what I want :-)
Kevin Seghetti: kts@tenetti.org, HTTP: www.tenetti.org GPG key: http://tenetti.org/phpwiki/index.php/KevinSeghett
Well, if you're going to go Linux, ALSA supports multiple sound cards pretty nicely, just tell XMMS (or whatever media player it will be) to use the different /dev/ devices (use devfsd). My first though was an implementation in Windows, Winamp also offers you the choice which soundcard you want to use, although one has to wonder about the IRQ hell of 6 of them in the same computer!
VNC wouldn't be such a good idea, because AFAIK it grabs the pointer so you'll probably end up with a situation where 2 or more people in different rooms wrestle for control of the pointer. A thin X display that connects to the server would work ok, although that would mean 6 computers in 6 different rooms, and when you already have that, it'd probably be wiser to have a "1 MP3-fileserver and 6 clients that draw MP3s across the ethernet" setup. Or you can just use SSH (or even telnet) to connect to the server and let them use mp3blaster, a text-based interface. Yeah, ugly, you can put it to the bottom of your list. But if the 6 clients need 6 "real" computers, it'll be so much waste - with SSH you can connect from a Palm Pilot, but then you'll need 802.11b for significant distances, and you can only get that from high end Palms..
But oh, depending on how long the VGA cable must be, you can always have 2 computers, each with 1xAGP, 2xPCI graphic cards and 3xPCI sound cards, and one of them as an NFS server for the other.. or even use the on-board sound. That should be easier to set-up, IMO.
Anyway, have a lot of fun, IMO you should document the process with lots of pics and put it up on a server, you can then wear the proud tag of "I've been slashdotted".
What time is it/will be over there? Check with my iPhone app!
One six minute Ogg file at 256 kB/sec takes up about 10MB of space, which translates to 10 hours of music per gigabyte. At about $1/gig, a 100 GB hard drive will cost around $100, and will hold 1000 hours of music, without having to rotate anything. Figure an average of 4 minutes a file, and you're looking at 15,000 songs, compared to 19 on a CD. A 50-pack of CDs costs $17, for 34 cents, and you'll need about 789 70-minute CDs, for a total cost of $268.26.
Since the CD option costs more per-song and is more inconvenient (since you have to change the CDs every 70 minutes), I'd judge it inferior.
Sigs are like bumper stickers.
I have to admit, I'm a head-over-heels lover of my SliMP3s.
/. ticker every 15 minutes on each unit, just because I can.
The reasons you should be too:
It's platform independent, but is also really tightly integrated into your itunes/musicmatch/winamp playlists. A single server, whatever your religion, can saturate the network before the server gets bogged down. This said, I recommend a Mac server, just because iTunes is amazing, and I really don't like having to deal with Linux config when I'm not being paid to.
$200/unit, and all the playlists on your network can be streamed from one location. At 10/100 speeds, it'd take about 15-20 of the things to saturate your network, if they were all running at the same time.
All of your libraries and playlists will be shared and distributed thruout the house. Doesn't matter if you're going to a boom box with a ghetto-wired cassete adaptor. Run cat5 to the room (cheap), and choose the most suited amplification method, from powered speakers, to a MacGyvered boom box, to a proper receiver.
The company is super cool, comes out with feature updates constantly, and the server software is open source, should you choose to use the built-in Perl powered httpd server versus just using a remote.
I'm not an employee of Slim Devices, just an insanely happy customer. That's a whole lot of elegance in a small, inexpensive package.
And it plays a mean game of Tetris, gives my weather report, and does a
put conduit in the walls instead of just running wires, that way later you can change the wires for the next technology that comes along.
Sure, if you've got more money than brains, you could do that.
But if you're going to wireless speakers (which invariably suck because there's another stage of conversion or modulation, then transmission, then demodulation), you could simply use centrally-located older machines (ie. cheap) and use wireless keyboards or other means to remote control them.
Lots of the solutions under consideration seem to involve having VNC hosts and other junk like that. Why? I don't get it. Here's how this former professional audio technician would do it:
Remember, sound quality is dependent on the electronic quality of the sound card you're using, not on the CPU speed of the processor. Generally, if it can play an MP3 without skipping, it's fast enough. DO look for *old* Creative Labs 16-bit ISA sound cards where the output amplifiers are in 8 pin DIP packages with "LM741" on them; in under 10 minutes you can bring them to almost the sound quality of the finest $2000 CD players.
And don't do stupid things that say "I think car audio is KEWL" and run unbalanced line-level audio all over the house unnecessarily. Run Cat-5 all over the house; run the sound card outputs to the amplifier as neatly and as shortly as possible in each room.
If you do it that way and have a good quality stereo system (ie. the speakers are actually made of wood and the amp claims it's only 50W but seems to weigh over 75lbs anyway), your fidelity will be limited mostly by the quality of the MP3s you're playing.
Fire and Meat. Yummy.
I'm also working on this exact same project. I'm planning to start a major remodeling job on my house starting this fall. Many of the things you are looking to do I'm also trying to accomplish. Here's the general outline of my plans:
;-) ) to play the same music. I will need to be able to adjust the volume levels independently in each room, as well as needing an easy way to "mute" a room or all of the music in all of the rooms, FROM ANY ROOM.
Bedrooms: I'm only running Cat5. Each room will have a custom built PC with a decent sound card and speakers. These machine are for the kids to watch videos, do homework, play games, listen to music, etc. Each of these machine will boot into some sort of GNU/Linux (right now the plan is Gentoo) as the primary OS. Unfortunately, they will also have a Win2K boot option for playing games. Util WineX/Transgamign goes GPL or many more games (thank you BioWare for NWN) go native Linux, I'm afraid that Win2K will remain in my, and my kids life.
Den, Kitchen, dining room, backyard patio: A pair of decent speakers mounted to the wall with the speaker cables neatly tucked away out of sight.
Family room: I plan on building a custom home theater PC running GNU/Linux that will be used as a PVR, TV, CD player, DVD Player, CD Ripper, DVD Ripper. Also attached will be a VHS for the older tapes. This machine will be hooked up to a nice 5.1 (or better) speaker system. These speakers will be "switchable" to also play "piped-in" music as well.
I have several "scenarios" that I want my A/V system to support:
1.Party: In this scenario, I would like to "program" all of the speakers in the Den, Kitchen, dining room, backyard patio, and family room (which will all be on the first for (except the backyard patio
2.Clusters of people doing stuff: I can see myself cooking dinner, in the kitchen, while one of my kids is playing with a friend in the living room. I would like to listen to my own music in the kitchen while my kids either watch videos (on the HTPC) or listening to "piped" music, radio, or Internet radio from a "audio server". The other rooms are "silent". In other words I can deliver independent audio to individual rooms. (By Internet radio I mean consumer Internet radio as well as shout/icecast)
I'm looking for an integrated/elegant solution. I would like an audio server in the basement that can be remotely controlled from each room that play music from an audio library of OGG files, Internet radio sources or radio tuner cards in any combination.
(I also plan to have a video server, actually a simple file server, with backed-up DVD images to act as a video server (thank you dvdbackup))
I don't want desktops or laptop scattered around the house actually doing the "audio work". I'm figuring that any PC on my home network can create/manipulate audio playlists that can be played in all rooms or an arbitrary subset. I will need to develop an "integrated remote control" system. I'm thinking of small, embedded, computers with an integrated LCD touch screen and networking that I will mount in the wall in each room on the first floor, as well as on the back of the house. These computers would provide a touch screen interface for controlling the audio in that room (with the option to control audio in other rooms or throughout the house). The controls would include volume levels, muting, playlist control, and the ability to choose from Internet or broadcast radio sources. In the family room it must also be possible to "switch" the speakers from the "piped" audio to the HTPC. When these wall mounted computers are inactive they would display the date/time and weather (or something).
I have also considered PDAs with 802.11 but I like the fixed solution from a clutter/aesthetics point-of-view. Also, PDAs like remotes will take a lot of abuse and tend to get lost. On the other hand, I have not ruled out the PDA solution yet.
Ok, now you know what I'm looking to do, here's where I'm at:
First of all, somewhere in the world, there's a webcast output plugin for xmms. Configure a copy of xmms to use it on the server machine, and point all your vnc sessions at that copy of xmms which is webcasting currently. Then you can have each of the smaller machines receive the webcast (just run a little daemon wrapper script around mpg123 that connects to the main server with a retry or something of the sort) and output it to their personal set of speakers with your method of choice.
You control music selections for the whole house from that xmms window, but i suppose you could have a local xmms window as well to play shared files from the server (or local files even) in a room-specific way. If you can somehow make the webcasting use broadcast packets or something you can probably minimize latency, but it could still be an issue (of course six sound cards would be only marginally better, since they'll all have different latencies anyhow, unless they are identical *and* written at the same time).
Of course the real stereo system style solution is to get a receiver with as many outputs as you need. six is commonplace and ten or twenty is not unheard of. Then you can run speaker wire (long distances if needed) to the locations. You can still VNC up those LCDs as much as you desire to. This, in conjuntion with a nice sound card would probably sound considerably better than your six sound card solution, though you'd never be able to change music in one room and not another.
If you use more than one sound card (either in one or many computers), you're going to need some way to handle latency differences. It really depends on how you use your house. If you can ever, in any appreciable way, hear two rooms at once then there's really no tolerance for latency differences at all, but if you're wiring rooms far from eachother (for instance the family room and the patio and the master bedroom, but nothing else), then the webcast solution is probably a better bet (and presumably uses existing wiring since someone asking such a question would be more likely to have run cat5 than speaker wire)
Good luck.
Brian
Their slimp3 and server already does this, over ethernet...
Save yourself the hassle.
I have had one since the first production run, and it's the best audio device I've ever bought.
Best of all, both the server and firmware are Open Source.
Chris.
-- I don't have a cool sig.
Buying each CD will cost money, no denying that, but if you listen to the original CD, you'll only have 10-12 songs instead of the estimated 19. Using the four-minute average, you'll then have 40-48 minutes of music until you'll have to rotate. You will not be able to listen to arbitrarily selected bands in an arbitrary order, which is part of the main reason of going to MP3/Ogg to begin with and doesn't have a particular monetary value. That's also assuming that the entire CD is worth listening to all in one go.
The licensing cost of 100GB of music will be the same regardless of whether it's on the CD or hard drive. While it may be cheaper to use the original CD medium, it will not be more convenient for listening to music selections in arbitrary order, so it comes down to a question of whether it's more worthwhile to avoid paying a dime an hour or to avoid changing CDs every 48 minutes.
Additionally, I believe it's cheaper to license from iTunes than from CD. However, I gather that this project may not be possible using the AAC files from iTunes.
Sigs are like bumper stickers.
You may be interested in Jukebox, it's what I wrote for our student union and it works like a charm.
If you launch multiple copies of it (it's written in C++ and not very memory-hungry), you can easily use it to serve over multiple sound cards.
I currently run it on Linux and FreeBSD.
Running symetrical multiple sound cards under any version of Windows or Linux is hell, I speak from experience. Although a Linux driver actually cured a cross channel hum problem I couldn't eliminate with Windows software and two SB 32s.
I have run two Sb 32 awe's with some success back when Creative actually spent some real money on it's audio designs. However the ever present 128 live version and up craps big ones. I made the mistake of upgrading, the good old 32 awe's are now back and doing the job! (I use my PC to quickly do audio recording of musical ideas I write/play, then I mix my composed parts to check my harmonies. I also have found that recording music snipets to harddrive is a good way to preserve new musical ideas and time stamp them).
I have an older asus p3 dual slot-one mother board with Pci and Isa slots and the sound is not too bad if you are not interested in high quality audio like 24/96 and up digital recording.
Signal to noise is no problem for audio companies anymore, the average "music consumer" can't tell the difference anyway. The new cheap crap I've heard with p4 and newer Sb cards is not even close in quality to the older expensive hardware.
My advice to you, if you are an audiofile, is not to use crap PC sound cards at all. Their drivers suck, their sig to noise ratios really suck on their line outs. Worse, the digital out is prone to interference interupts from within the PC, (emr caused by fans, cheap drives etc). The PC sound card is the biggest (P)iece of (C)rap ever to polute the world of music.
Use real audio devices not crappy, hyped up toys like PC sound cards!
OH THE SHAME I fell off the wagon and use sigs again!
BPM Studio Gastro Can output 6 independent mp3 streams with a suitable sound card(s):
http://www.alcatech.com/
I've been happily using their DJ software for years.
from the website:
The BPM Studio Gastro Features
Sound management from one central system
Arrange different playlists with the music of your choice and
direct them to each of the 6 areas.
Control your playlists, volume and sound needs for any area
in realtime.
Intelligent playlists
(store titles in any order, sort and rearrange them anytime)
Archiving of several 10.000 titles possible
Comprehensive drag & drop support
Not to piss all over the hax0r spirit, but why not look into something like the Audiotron from Turtle Beach. It's a bit on the pricey side, but it's great for serving up (actually receiving) MP3s to a stereo over CAT5 from some machine in your home.
Uncle Eazy
HE DOES NOT NEED 6 SOUNDCARDS FOR 6 DIFFERENT AUDIO-STREAMS !
He needs a server, that can STREAM 6 different BINARY streams to 6 different thin clients in his house.
In addition, he will be able to watch MPEG4 also, adding a little of decoding power to the clients.
It wont be much more expensive than putting an amplifier into each room. (Because this will be a need in order to get somewhat decent quality)
Multiroom is ethernet these days... I just don't get it so few really realize.
And with such thin-clients (for audio any 99 Euro [+RAM] EPIA 533MHz thin-client [fanless, diskless]+ PC speakers will do, add 70USD for MPEG4, add 250 Euro (client needs DOC/DOM, so more expensive) for DOC/DOM local boot) you have IRDA so no need for WiFi/PDA remotes (which such anyway, as long they do not do the Bluetooth trick)
amix (not logged in)
My house is wired with CAT5, every room
leading down to the server room with a
couple of patch panels.
Taking my trusty Dremel I modded some
CAT5 cables so that output from my MP3
player went into the wall and came out
in the server room. Now took random
patch cables and hooked-up outputs around
the house. After this success, I devised
two CAT5-to-speaker cable types (LEFT and
RIGHT) that let me hook up speakers in
any room in the house.
Actually, it works well. I never thought
UTP would carry the speaker signal, but it
does, and the computer network does not
seem to mind.
Ceci n'est pas une signature
You should donate to the EFF or some other charity.
You can replace the LM741 with any number of audibly superior amplifiers. Here are some to try (in Order of quality). AD711, TLE2071, 5534 (must put a 20 Pf capacitor beween pins 1 and 8), TLO72, LF351, TLO81 (available at Radio Shack). Any of these will blow away the LM741 sound wise.
Like I said with regard to the costs, you have to license the music regardless. Putting it through a computer jukebox is just an expression of that license that requires further costs. Hence, you must compare straight CDs to licensed music + the media access system for a computer. You cannot compare the storage for copyrighted media to the cost of licensing the media.
I have had a house-based MP3 server running over NFS for years now... My solution has been to have a stereo near each computer that has local ethernet access, and just run the output from each computer's sound card to the stereo next to it. I have customized shell scripts for Linux, FreeBSD and Mac OS X that take the best advantage of the system's ps, mpg123 and kill programs -- if you would like a copy (and instructions for use), email me.
While this setup allows for independent songs to be played on each system (which is great for most purposes), there are times when you want to play the same song on each system -- in essence, creating a "concert" around your house. To do this, I set up Icecast on a Linux machine, gave it all of the MP3s to play, and then connect to it from each other computer via mpg123. This approach does work, but the result is less than excellent -- each connection can be timed up to a second or so off from the other ones, which creates a really weird echo effect in the house. While this can be fun for a little while (standing between two stereos you get a "live" effect from studio material), it gets old real quick.
My proposed solution to this would be find a low-power FM transmitter that you can hook up to one machine -- play MP3s from a soundcard into the FM transmitter, then tune each other stereo to the FM frequency that the transmitter is using. I must admit that I haven't tried this, so I don't know how well it would work -- I do know that the signal would sound synchronized because radio waves travel at the speed of light. I know that Griffin Technology makes the iTrip, which is an FM transmitter specifically made for Apple's iPod. It claims to only have a 10-30 foot range though (limited by FCC regulations), so I'm not sure how well it would work. I'm sure there's a company or two out there that makes a low-power FM transmitter that would work well on any output source, in any situation.
Slashdot's first reaction to VMware
or NMM for short, might be a software option. Every piece of hardware is considered as a "node", and it doesn't matter where this hardware is located in a network. A so-called serverregistry is aware of every speaker, monitor etc and handles sources of video & audio towards desired output devices (sinks).
From their website: "The goal of our work is to design and develop a multimedia middleware, which considers the network as an integral part and enables the intelligent use of devices distributed across a network. We are currently designing and implementing a network-integrated multimedia infrastructure for Linux (as well as other operating systems). Our unified architecture will offer a simple and easy to use interface for applications to integrate multimedia functionality. Therefore, it can be used as enabling technology for traditional multimedia applications, but also for ubiquitous computing and mobile computing. The result of our work will be made available as Open Source (LGPL and GPL). "
As far as I know there will be a cvs repository soon, and, of course, there is no ready-to-use application for the situation you describe here. But there's a tool called "clic" which is part of NMM that can be used to connect a bunch of nodes (for example the MP3ReadNode with the PlaybackNode), maybe the way you need.
The low cost answer is a program called Media Center. It offers multi zone playback, among other things. You can use this to control/maintain your mp3, video and photo collections, and send out different streams to different zones. If your computer has the components, it will also act as a Tivo. I use this along with an Audiotron & an Ipod, and find it works great.
Media Center feature list.
You can replace the LM741 with any number of audibly superior amplifiers. Here are some to try (in Order of quality). AD711, TLE2071, 5534 (must put a 20 Pf capacitor beween pins 1 and 8), TLO72, LF351, TLO81 (available at Radio Shack). Any of these will blow away the LM741 sound wise.
Precisely. I think Fairchild only designed the 741 as an instrumentation amplifier, so I don't know why they even ended up in audio. That being said...
Lots of audio equipment through the years has used the LM741, which is very noisy (hiss in the audio). I've even seen a 1970s Allan and Heath professional 64 channel mixing console. I pulled the line card out of every single channel and plopped in an LF351, all of a sudden the board was useful for more than just PA at stadiums.
Old Creative Labs SoundBlaster 16s (long 16-bit ISA cards with hardware settings jumpers) had LM741 on the output stages, later versions used a dual LM741 (an MC1458, if memory serves). These ICs are still made mostly only for compatibility; there are lots and lots of pin-for-pin low noise equivalents that you simply put in place of the 741/1458. The old SB16s also had good spacing between the digital and analog sections (build a Faraday cage, soldered to ground, around the analog stages!), used conventional components (none of this SMT crap) and had the same excellent D/A converters as some CD players. In later SoundBlasters, much of the logic and the D/A converters have been folded into the same custom chip to cut costs. But you want to keep the audio as far from the computer's bus as possible; the other side of an IC is not far enough away.
Computers: No. Can't even scoop one for myself. Each computer is accompanied through its life cycle by a pile of papers which would make the IRS jealous. It's horrible, it's tragic, I agree.
486 not playing MP3s?: When Napster first came out, all I had was a 486DX2-50. (I didn't do any multimedia stuff, so I didn't need power.) It played MP3s fine, and so has every other properly configured 486DX I've tried - WinAMP or Windows Media Player or mpg123 - under Windows 95, NT4, Red Hat 5.2. Sure, the CPU is 83% busy to play one song, but it works, without skipping or kicking down to half or mono modes. Turn off all the crap in your Windows startup and system tray.
DMA is your friend. DON'T try to stream an MP3 to a 486 using an NE-2000 network card. Get something a little more refined for the NIC.
Fire and Meat. Yummy.
OK having done this in the last 12 months lets go over the options.
:)
Slimmp3 and Ethermp3nut or whatever are out there and work well for ethernet attached 2 channel audio. I went with the free as in speech ethermp3nut (right name?) as I'm handy with a sodering iron and have friends that can deal with surface mount. These along with a small amp are good for rooms that you only need 2 channels like the bathroom porches etc pretty much anything without a TV. I have 4 drops of Cat5 in every room (one per wall) and use cheap gige agrigation switches from netgear if I need more ports.
OK now for rooms with TV's my primary concern was the TV room I places the server directly below the TV and install some metal piping to chace cables through (grounded to keep any interferience down) The only thing running analog to the TV is the VGA cable and the Svideo cable running to the receiver the audio comes off a standard sound blaster audigy via fiber to the in room receiver. Firewire and USB 2.0 got chaced up as well to run a DVD-R drive in the sterio rack for DVD/CD playback, ripping and recording. A few pairs of cat 5 are used for IR Blasters and receivers. Video is provided via a Matrox 450 Maxx one out used for the VGA to the TV and the other running svideo to the receiver in the TV Room. The TV room has server method of controling things there is a wireless keyboard and mouse, normal remote comands via lircd (more on this in a moment) a dumb terminal a Palm with IR and any laptop that can get on the 802.11g network. Finialy I'm currently working on adding speach recognition for the complete hal look
Other rooms have a pretty standard key pads and screens that work via serial 3 wire. I hacked together a little application to scroll whatever song is playing information and navigate premade playlists that are then passwed back to mpg123 to play it's not perfect but works ok next revision is speach recognition. If thy were close enough (first floor) I used a cheapish 12 channel out 8 in profetional audio card they are easy to come by and generaly support linux check out some garage band supply store to find one, each output looks like a seperate DSP at the application level but still only one IRQ. Because it's a real audio card it outputs a balanced line signal these are much easier to run at distance without interferience. At the other end are pretty straight forward project amps and speakers in the walls I didnt need to go that big wattage wise so these were easy to construct.
Now for the few places that I wasent comfertable running balance line to I used the ethernet to line converters and a receiver this for me was the garage it's detached from the house so I ran multimode fiber a few inces below the ground picking up some cheap 10/100 fiber cards off of ebay and installing them into the linux router with bridging and a boca terminal in the garage thats also hacked to support bridging (have my old 802.11b AP out there for the car) I could have used the audio on the Boca but it just sounded bad (I tried this first) the terminal runs mp3blaster via an xterm to the core server.
The other special room is my bedroom it's the only other TV in the house I have an old trident PCI card that can be jumpered for TV out only (This is a GREAT feature) and that runs a Svideo up (need a booster seeing some artifacts fromt he run) I have a DEC color dumb term attached to an old 9 inch monitor and keyboard in the corner it's directy connected to the server on 3 lines and generly runs mp3blaster or lynx to get to the video playlists and startup mplayer for those. I used 3 ethernut's to give me 5.1 for the receiver in the bedroom and am working on getting mplayer to connect to them correctly.
OK now to the server it's a doul proc Xeon 600 with 2 megs of cache each that I had laying around. Primary video out is a Matrox 450 Maxx secondary is a trident on PCI. I have a few 4 channel out CAD cards that use PCI that can handle the video but need to get scan converters / T
No sir I dont like it.
you're too good for two cups and a string for audio? *hrmph*
Blessed be he who reads this post, Cursed be he who tells my boss.
There's actually a reason you don't see this done more often: Unamplified audio (like the stuff coming from a soundcard) doesn't travel very far. 20, 30 feet max before you start getting signal degradation. You'd be better off getting 4 cheap PCs with cheap soundcards and mounting everything remotely over NFS (and there are already stereo components that do this exact same thing.) I know it sounds like a fun project, but you can buy products like this that allow you to access your MP3 collection and control it remotely (via http, remote control, etc.) Basically, you're gonna need some sort of player at every amp, otherwise it's just not gonna sound good.
We used a PII 400 and got a very reliable 5 output stream box using a multi-output card that isn't manufactured any longer. I tried a number of these cards and most of them worked well. [ As an aside, the MOTU high-end units are excellent if you are going to put the output into high-quality amps and speakers, but they are expensive.]
From the software side, we used a custom, multi-threaded MP3 player compiled using Intel's optimizing compilers (which mad a huge difference on the PII) and used a graphical front end with a screen-per-room display showing the album art (scanned in by the user or installer) along with the tracks, play lists, etc.
We did run into a control problem, even though most of our customers were using systems with centrally located gear, which was that getting a PC to run with multiple distinct (and user-uninterruptable) displays simultaneously was expensive and difficult. To supplement this, we created a serial-based interface which allowed for play lists, random play, and basic start/stop/skip controls for each room and could be combined with the GUI over a commercial home control system (like Crestron or AMX).
Basically, we would watch the serial port for commands and respond to the control system by flipping individual windows that corresponded to the room that was controlling the system at the time. The control system, in turn, would put show the screen output in a kind of touch screen mode and send mouse locations over the serial port back to our controller. This worked, but was expensive and complex to handle, since only one room could have control over the GUI at the time. For things like displaying the playing tracks and album along with the next track and providing basic control of the start/stop/skip/repeat sequences, we could send text to the control system over the serial port and it would be displayed on the screen in text fields (allowing the main display to be required only for play-list management). This helped quite a bit.
The control piece was far and away the most difficult part of the project, but since you only have to satisfy yourself, and not the marketplace, I'd suggest that you might find an 802.11-capable PDA as a controller might be useful (and fun to work on). Of course, then you have to either develop your own control protocol or use some kind of CGI and a web server to do the control, but if you separate the players into individual threads or processes that can be easily located, you should be able to send messages (UNIX signals, perhaps) to them and get the level of control that you need.
From a technical perspective, any OS that has preemptive threading and good interprocess communication should be fine for building this kind of system. We found that by creating our own player (despite the need to license the decode patent from Fraunhofer if we were to sell it commercially), we were able to get a finer control of the playback features (such as pause/skip/repeat) than by using single-shot mp3 play commands that were available at the time. I'd suggest looking for how you can get those useful features if you decide to use existing commands in a Linux environment.
Of course, on a Macintosh, you can do the playback through QuickTime, which is going to be easy and highly-controllable, so you have that oppotunity too.
In the end, we found that the customers who got it loved it, but that the installers we were trying to sell to weren't interested in buying a product that required some set-up.
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I already have something which does what you want - I am using a Slimp3 server to stream mp3 data to multiple players around the house (across a wireless network). I have 3 players and they are all able to play a different stream and all at once over a regular 10Mb/s wifi network (all my CD's are encoded to 128Kb/s mp3s)
.5 seconds out which would sound disconcerting to say the least if you were within earshot of more than one player.
If you ran long cables from 6 sound cards to 6 amps around your huse, this could be made to work, but the losses across such long cables would be unacceptable to all but the most tone deaf.
You can get details of Slimp3 from http://www.slimp3.com
One thing it won't currently do (and may never do to acceptable levels of timing) is play the same stream , in sync, to multiple players. Even using multicast, they might be up to
However, if I undertsand your requirement , this (or any other digital music serving device) will do it justice.