Linking 5 cars via tether for streaming

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Wud up doh ladies.

Heres my predicament, my buds and i are driving up to daytona for SBN (spring break nationals, a bass competition) and were basically driving in a caravan.

Each car has at least 5000 rms and up to 15000 rms. (watts)

What we thought would be epic was for me to be djing off of a laptop on the way there, connected via ustream and all 5 cars tuning in to my stream allowing us to play the exact same songs at the exact same time from the 5 vehicles making you be able to hear us from a mile or so away :P

Predicament. To my knowledge, we have an ipad with ability to tether and nothing else as or right now considering i havent really looked too far into it.

However, We do have a power converter in one of the vehicles allowing us to use a wall outlet essentially.

I was entertaining the idea to have a router connected and to be streaming via a shoutcast server over LAN but im unaware of any app that allows you to tune into shoutcast radios being broadcast over a lan on itouch or ipad or iphone or android for that matter. I am aware that winamp allows you to plug in your listening IP but i have never tested it to work over lan nor on an android and i dont believe its on iphone etc.

So my alternative was to leech internet off the ipad, but if the caravan is 5 cars long, will all cars be able to reach the signal from the ONE ipad, and will that ipad have enough bandwidth to have me dj (upstream, upload) and 5 devices stream (downstream, download). Audio will be streamed at 48kbps if i remember correctly so the bandwidth required ISNT massive however over 5 devices i believe it might be an issue.

if the bandwidth is sufficent i was entertaining the ability to attempt to use the ipad as a WAP (Wireless access point) connected via the router then have an antenna from the router on the roof of the car to boost distance you can pick up the signal from.

WTB ANSWERS, i have 3 weeks to get this to happen

I doubt very seriously the wifi antenna in the iPad is capable of handling this sort of abuse.

You might be able to do it with a laptop and a wireless AP in infrastructure mode and have multiple clients connect to that system.

Originally Posted by Regizzle

Wud up doh ladies.

Heres my predicament, my buds and i are driving up to daytona for SBN (spring break nationals, a bass competition) and were basically driving in a caravan.

Each car has at least 5000 rms and up to 15000 rms. (watts)

What we thought would be epic was for me to be djing off of a laptop on the way there, connected via ustream and all 5 cars tuning in to my stream allowing us to play the exact same songs at the exact same time from the 5 vehicles making you be able to hear us from a mile or so away :P

Predicament. To my knowledge, we have an ipad with ability to tether and nothing else as or right now considering i havent really looked too far into it.

However, We do have a power converter in one of the vehicles allowing us to use a wall outlet essentially.

I was entertaining the idea to have a router connected and to be streaming via a shoutcast server over LAN but im unaware of any app that allows you to tune into shoutcast radios being broadcast over a lan on itouch or ipad or iphone or android for that matter. I am aware that winamp allows you to plug in your listening IP but i have never tested it to work over lan nor on an android and i dont believe its on iphone etc.

So my alternative was to leech internet off the ipad, but if the caravan is 5 cars long, will all cars be able to reach the signal from the ONE ipad, and will that ipad have enough bandwidth to have me dj (upstream, upload) and 5 devices stream (downstream, download). Audio will be streamed at 48kbps if i remember correctly so the bandwidth required ISNT massive however over 5 devices i believe it might be an issue.

if the bandwidth is sufficent i was entertaining the ability to attempt to use the ipad as a WAP (Wireless access point) connected via the router then have an antenna from the router on the roof of the car to boost distance you can pick up the signal from.

WTB ANSWERS, i have 3 weeks to get this to happen

Sounds like a pretty sweet idea dude! If I were in your shoes, I would create a powerful, rolling, WiFi LAN. Here's how I would do it:

Here's what you would need:

VLC (it's free)
A really powerful wireless router with external antenna's
Make sure the laptop you're going to be performing the broadcast from has its own wired network adapter

What you would do:

Connect your laptop up to the WAN port of the wireless router (the same port that you would normally connect your Cable Modem/DSL/FiOS). This is because you want your laptop to be set up as the default gateway for that LAN.

I would perform the broadcast from the middle car in the caravan for the best signal to the rest of the vehicles, possibly even use external antenna's (like, external to the car itself, not just the router) for the best possible signal quality.

Set up a local VLC streaming server on the laptop. This way you can make the stream much higher bandwidth and higher quality. Everyone can tune into with their own VLC client's, whether on other laptops, or iOS/Android devices with VLC.

Done correctly, this setup won't even require an internet connection, as everything will be done via the local network. That said, if the broadcasting laptop has a mobile connection tethered up to it, then everyone can benefit from that if they wanted to.

Overall, the mobile WLAN idea, in conjunction with a local VLC broadcast, will afford you the best audio quality along with the highest degree of reliability, as you won't need to worry about dead spots in the mobile coverage. Also, this method will yield the lowest latency (because they'd all be on the same local network), so for everyone in the caravan, their stereo's will more likely be playing the same thing at the same time as opposed to everyone playing the same thing, but all at different parts depending on their cellular network conditions.


What do you think?

Will the router do it? Unless it's a real piece of junk, yes. (And by junk I don't mean something selling new for $19.99, I mean something real cheap. Even a $20 router should handle 5 audio streams without waking up.)

Will the idea work? Not the way you want. There will be a delay of up to a few seconds between the streams to each car. All the cars can hear the same song at (within a couple of seconds at most) the same time. But close enough that there's no echo? No.

Connect a computer's web browser to a web audio source (police scanner, or anything else where the source doesn't start by your connecting to it, like a podcast will). Connect your phone to the same source (using its browser). Notice that there's a delay between them.

Nothing you can do about it - that's just how streaming works these days. Maybe for SBN 2025.

With encoding and decoding of digital audio streams, signal quality, et cetera.. you'll find it hard to achieve a truly synchronized stream. With new ATSC broadcast standards, even television sets in my household are off-sync; there is an echo.

Here's where analog synchronization comes in. It might seem very old-fashioned, but you could use an FM transmitter for this. I don't know much about them, but be aware of FCC regulations here in the states. You'll need a fairly high-power one and an omnidirectional antenna. Plan on a nice big investment, too!

Some cons to an FM transmitter:
1. Reliability: it's RARE that you'll find a vacant station in a metro area. Broadcasting over live stations is illegal, and requires a LOT more power than you can get in a portable FM transmitter.
2. Security: the music stream is unprotected. Just about anyone nearby could pick up your station and use YOUR tunes.
3. Vulnerability: it's possible that someone else could bring a more powerful FM transmitter, and broadcast Justin Bieber to your five vehicles (yikes!)

It'd probably be easier to store local copies of the music in each vehicle and use a network connection to handle synchronizing hitting the "Play" buttons.

But you'd probably have to write a whole new application.

Originally Posted by dfc849

With encoding and decoding of digital audio streams, signal quality, et cetera.. you'll find it hard to achieve a truly synchronized stream. With new ATSC broadcast standards, even television sets in my household are off-sync; there is an echo.

Ya, anything that encodes and decodes is very likely to do it at a slightly different rate, so synchronization would be very difficult. Even if you could get them started at the same time, they will probably slip out of sync after some time, too. This goes for the idea of just pushing "play" at the same time. Music playing at slightly different rates may sound the same to us, but will shortly fall out of sync.

Originally Posted by dfc849

Some cons to an FM transmitter:
1. Reliability: it's RARE that you'll find a vacant station in a metro area. Broadcasting over live stations is illegal, and requires a LOT more power than you can get in a portable FM transmitter.
2. Security: the music stream is unprotected. Just about anyone nearby could pick up your station and use YOUR tunes.
3. Vulnerability: it's possible that someone else could bring a more powerful FM transmitter, and broadcast Justin Bieber to your five vehicles (yikes!)

On the other hand, to broadcast only a few hundred feet you could probably get something at a computer store that would handle it. I know I picked up a $10 FM transmitter meant for iPods and CD players to connect them to a car stereo. It transmits from my computer to my stereo about 50ft away with no problem, though I haven't tested the limits. It would be easy enough to just plug it into your DJ machine and set all the cars to the same radio station. You could try sticking it to the top of the car and see how far away the other cars still get a clear signal. If it's not enough, you could probably pop it open and extend the antenna a little and get better range.

Where are you driving UP from? Cuba? All of that for a 4 hour trip if you are as far South as Miami?

xpather that

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Cool idea

i'd go with analog, i.e. FM transmitter