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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/
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.
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.
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
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!
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.
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.
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.
Wireless speakers are considered by most audiophiles to be of poor sound quality.
This of course assumes an analog signal.
Also if you wanted to run one song in one room and another song in another room there could be interference issues.
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
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..."
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.
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
I program these types of systems for a living. Usually, everything I work on is HUGE. To put in in perspective, I recently finished the control system in the Chuang Residence. Alfred is very much into the latest and greatest - and had a 3 million dollar home theater put in (seats 7) as well as A/V distribuition (30 zones) throughout the house (61" HD plasma at the foot of his bed!).
So, it depends on the signal that you're routing.
Amplified: Great! it'll probably go as far as you need it. If you're going over a few hundered feet and don't care about the quality (think outdoor speakers), you'll want to look into doing with 70 volt transformers and matching speakers. (the higher voltage will drive the signal much farther, but the audio quality goes to hell). Generally with amplified signals the farther you go the quieter it gets.
Line level (non-amplified signal): Will often work just fine. Since it uses a much lower voltage it is much more succeptable to noise. The two biggest things to watch for are interference and ground loops. You get interference from power sources, running motors, wireless devices, etc. If you convert the signal to balanced it'll be less succeptable to interference (a balanced signal provides a ground reference). Small converters are available from several sources. Ground loops are caused when there is a voltage difference between the "ground" plane on either end of the wire. Often, you'll hear a slight 60 Hz hum. The PROPER way to eliminate this is to make sure all your equipment uses the same ground. If it's all on the same circuit in your house, then you're probably OK. If not, there are small inline devices to eliminate this as well. Look for "Hum Buckers" or "Electo-Optic isolators". Line level will go a suprising distance but you'll want a distribution amp to go over about a hundred feet. Keep in mind that the farther you go, the better chance of having noise problems.
Digital: Bleh! I really want this to work, but I haven't seen a successfull installation with more than 20 feet of wire! I worked one job where they tried both optical and copper but couldn't get it reliably (trying at about 75 feet of signal). When the signal degrades, the audio just goes away - not quiter or noisier. It suprises me that the optical signal won't go farther - it's light dammit! The issue seems to be that the TOSLink cables are designed around a plastic core that is easier to work with - but attenuates too much over distance. Having a device to rebuild the signal every 20 feet is problematic to say the least.
Never never never smoke crack before geometry class!
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:
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.
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
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.
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
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.
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.
O