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streaming audio between PC's? Answered

i would like to be able to connect my laptop's audio somehow to my PC
first i thought i'd just connect the headphone out to the mic in on my PC, but that gives *alot* of interference, altough i do hear my music

after that i tried searching for some software that would just stream it to my PC, but all i could find was software to stream to PS3's, stereo's and other stuff

so my question is:
how can i stream/connect the audio from my laptop to my PC??

solved with a couple of resistors in the cable


There are a number of free tools to stream audio on a small-scale basis. Microsoft has one, which the Windows Media client knows how to connect to; that might be all you need. I used it a few years ago to get audio from one end of a hotel to another through a WiFi link.

Shoutcast is a somewhat more serious solution, still free -- but that generally bounces the audio off a third machine (sender/server/receiver configuration), which seems a bit more complicated than you're looking for.

There are others. Websearching "streaming audio server" will find them; that's how I first found those two.

HOWEVER: Let's go back to the actual problem for a moment.

Your original mistake here seems to be that you tried to feed headphone-level audio out to _microphone_ in. You need to feed it to the _LINE_ input jack. Or, if your soundcard doesn't have line input, you need to attenuate the signal down to microphone level. Otherwise you're overloading the input preamp and you're guaranteed to cause distortion. Attenuation plugs are available from Radio Shack and the like; basically they just put a sufficiently large resistor in series with the signal. (I forget the exact value; a bit of websearch should answer that too.)

If, after fixing that, you still get 60-cycle hum on top of your signal, that's probably a Ground Loop problem. This happens when the two pieces of equipment are plugged into different power circuits in the building. An isolation transformer can be used to solve this problem... or you can just make sure everything is plugged into the same set of outlets. (Or, given your setup, you can unplug the laptop and run it off batteries for the duration.)

If _that_ doesn't solve it -- if you're picking up a local radio station or something of that sort -- the only answer may be shorter cables and/or to not use the mike input -- which brings us back to the recommendation that you use line input.

Sanity check question: What are you actually trying to accomplish here? Do you really need the audio going from one PC to another, or just from a PC to a remote amplifier and/or set of speakers? The latter may be a lot simpler to set up.

thanks for this, all the options look promising, and im going to check them one by one till i find a working solution

as for the sanity check, my setup seems a bit out of order, but it's the easiest to use (after everything works)
right now, i have my PC connected to my TV, the TV to the stereo, but i also made an audio switch so that i could switch audio to my 2nd monitor
also, my PS3 is linked to my TV (hdmi cable)
this way, everything in the end comes to the TV and the stereo, on 1 channel

the line in doesnt quite do it, it gives the same result as the mic in
i've just finished one of those cables you mentioned, and altough it does make the squeeking and interference go away, it makes the volume go down alot, so il try and make a small op amp when i get the parts for it

the schematic i've used:

R channel ------R1-------|-------- line in
gnd ---------------------------|-------- line in
L channel --------R2------|---------- line in

where R1 and R2 are 1mega ohm, and R4 and R5 is 10Kohm
going to try the shoutcast now, wich if works is very usable since im going to setup a PC for hosting stuff like that (teamspeak for example)

ugh, instructables messed up my improvised schematics
the R5 and R4 are supposed to be where the | are, so behind R1 and R2

i've got that cable working, thought that if i changed R1&2, i'd get more volume
so i experimented a bit, and changed R1&2 for 10Kohm resistors
no distortion, squeeking or interference whatsoever, and a normal volume (max=too loud, min=too low)

Seconded ork's suggestions -- use 'line out' if you have one, and/or line in on the other end.

Turn the output on the laptop WAY down (to about 25%) and the tv to no more than 50%, then use the actual stereo to amplify. If the TV has the option, use 'passive audio' or the like that makes the tv line out exactly the same as the line ine.

Software, pretty much anything you 'stream' will have a lag, which is no good for you probably, unless it's just for music.
Winamp has support for 'shoutcast' servers. I recommend AnalogX SimpleServer: Shout. Free, and 1 button operation.
Basically, you use winamp to play your music, (or mix in a line in from microphone and stream that, etc), and change the output plugin from 'your speakers' to 'the stream server'. From there just point the audio software on the other machines to the IP address of your laptop, bam, network audio. Quality is controllable, and over a local network you can afford to use extremely high quality without a lot of network traffic.

even when the laptop's volume is off, i get this interference/squeeking

going to check that software you mentioned, becouse it's indeed only music and as long as it doesnt have a HUGE lag, it's prolly workable

okay, i got it running (winamp and simpleserver) but how do i listen to it?
i've tried the adress that stood at the top of simpleserver (in itunes and firefox) but didnt get anything at all
guess that's the wrong way2go, and on analogX's site, it doesnt say anything about tuning in

use another copy of windows media player or winamp, and say play: internet location, then put in the IP address.

i prolly won't buy one, gotta do it cheaply :P

and both my laptop and desktop are plugged in the same outlets, so according to what ork said, its not possible

hmm, i just tried disconnecting my laptop from the mains, and all the squeeking is gone
so aparently that problem is there, but it doesnt fit the description of 2 different outlets...
going 2 look into that isolation thingie, maybe i can DIY one xD

.  If you want to go the audio cable route, you can get an attenuating audio cable at most electronics stores.
.  Personally, I'd just set up file sharing (Google yourOS file sharing, eg, "Windows file sharing", "Linux file sharing") and use standard Ethernet crossover cable.
.  You should be able to find instructions for all that right here at Instructables. Google The search bar is your friend.

as i said, with the cable (that i already own) i get alot of squeeking, interference and all that crap

i should have mentioned i can't use file sharing becouse i wanna listen to that music during a game, but be able to switch it off quickly without switching programs

i really need something that only streams the audio (cable or cabless, i dont care) to my PC, realtime