2 PCs + 2 Laptops to 1 headset

[peng$ter]

Hi folks,

Not sure which forum to ask my question. pls excuse.
How can I get audio from 4 computers to my headset simultaneously?
Is there a h/w device or s/w app to do that?

I've tried the following already,..
- an audio selector/switch : not simultaneous, switches one output at a time
- winamp + shoutcast: not realtime, buffered, works if only listening to music tho
- ventrillo/teamspeak : not realtime enough, theres always a 1 sec lag
- audio mixer : very expensive

What I want to do is listen to music without annoying my MMORPG buddies.
Get notified by skype (alarm) when my gl calls my laptop.
While waiting for game loads I can hit a macro key to watch the news.
Each of those things runs on a different computer simultaneously

Would be a bonus if I can also switch my mic between the computers too
right now, I'm just plgging n unplugging my mic jack between my game and skype computers.

thanks in advance
peng$ter

 

[royalcrown]

even if there is no lag due to 4 machines, your internet connection WILL "lag" or delay your teamspeak without a proper switch and nic that do QOS.

You might want a KVM, that shares audio. or use a headphone splitters and jury rig them.

 

[Twoboxer]

Can your PC's audio combine Aux-in with PC sound to output (both combined) to speakers? If so, you could try daisy-chaining the audio, PC1Out = PC2LineIn, etc.

 

[505090]

radio shack has 2>1 splitters and couplers for headpones

 

[xtc28]

twoboxer is on it I think...... it works for me

 

[Twoboxer]

505090's idea, done from the parts bin:

http://smphoto.wordpress.com/2007/04/09/super-simple-audio-combiner/

 

[xtc28]

I think its a good Idea........ BUT, have you ever heard the ground noise of a setup as such? splittersand suchare not designed to split that many times. Signal degredation and the emminent high pitched whine are intolerable for me. For my setup I use line out to line in one after another to attain near perfect sound the shorter your wires also will play a part in your sound output. Your wires should be as short as possible (without stretching the line)

 

[peng$ter]

Thanks for all the great replies, folks.

I was hoping this is old news to somebody and he/she could just say "peng$ter, you just need a so-and-so thingy from BestBuy". At one point I was ready to lay down $199 for a cheapo mixer, but I figured in this day and age. Some manufacturer might see a niche from multi-computer owners like me to make a specific plug-n-play type device

Surprisingly, teamspeak does not lag so much. Maybe because my LAN is gigabit. But it is still too weird to watch movie from another computer. Yeah, I watch the news from my laptop while playing games.

At least 1 of my desktops can (or have software) to mix multiple audio streams. But what does daisy-chaining mean? Splice all the wires and simply twist their coppers together? don't I need to have something to filter for noise and ground humm and such?

I have actually found the "Super Simple Sound Combiner" webpage in Twoboxer's reply during my own research. Alas, I'm not geeky enough to know how to make use of that excellent schematic by samlimlister, even if I got my rust-encrusted solder to work. Does radioshack sell those resistors too? Nevertheless, thx twoboxers

505090, Whats a "coupler"? Is that like a reverse 2-way splitter?

peng$ter

 

[123urpked]

Do you really need to watch the news, listen to music, talk on skype, and play games all the same time? How can you even process all that going on at once lol ? Anyways.. Why can't you just mute your mic on skype while listening to music and you can still hear your friends.

 

[Twoboxer]

For laughs, I put this together from that schematic. This $15 project might be within your Geekiness:

4 x Stereo mini-plugs, with 6' wire @ $2.70 each
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=CP-2207-ND

6 x 10k, 1/4W, 5% resistor
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=10KQBK-ND

We will make a cable to combine the stereo output from 3 PCs, and feed it into your 4th PC as "Aux In". From there it would mix with sound from your 4th PC, and be available in your headphones.

Look at the plug-and-wire picture at the link. Click on the picture to enlarge it. You see a red wire, a black wire of the same thickness, and a thicker black wire (that we will now call the "shield").

Step 1) Take one of the stereo min-plugs and wire assemblies, and mark it "Output".

Step 2) Take the OTHER three plugs and connect one resistor (doesn't matter which end) to each red wire and each black wire (not the "shield"). Cover the connection from wire up to the resistor body with electrical tape. We now have 3 Red and 3 Black wires that end with a bare resistor lead.

Step 3) Join the 3 Red wires with resistors attached by twisting the open leads from their resistors together. Then connect the Red wire from the output plug (Step 1) to the joined resistors. Cover this entire connection, including resistor bodies, with black electrical tape.

Step 4) Repeat Step 3 using the Black wires with resistors.

Step 5) Connect the 4 Shield wires together, and cover with electrical tape.

Done. Plug the one you labeled "Output" into the Input Jack on the PC that has your headphones, plug the others into the Output Jacks of your other PCS. $15, enjoy.

You can also wrap aluminum foil around the part of your new cable that is electrical tape, shielding it. Then wrap the aluminum foil with electrical tape to protect the shield.

 

[peng$ter]

wow Twoboxer,

Nice guide. I'm motivated to try it now. Guess I better go buy another solder. I take it when you said "join" that I should solder the wires together. But I have a question. Would this setup/circuit eliminate noise? When I tried using an audio selector, I got terrible grounld-humm from my laptops. Nevertheless, thank you very much for putting the guide together.

123urpked, of course I do not do all that simultaneously all the time. But, its fun to get my computers to do exactly what I desire. Instead of the other way around. But think of it this way. I would be perfectly happy to let all audio come from the pc speakers themselves. But unfortunately my kids are sleeping in the next room. So I have to duplicate all that inside my headphone. So skype is not the only thing I'm trying to solve. But thanks for the suggestion anyway.

 

[Twoboxer]

Neither you nor I know the validity of the circuit. It may be that different resistor values (for our version) may work better. But for the price and the elegant simplicity of the solution, I thought it was worth a shot. If I had your need, I'd try it lol.

Dunno about eliminating all, some, or no noise lol. I gotta believe there are $X00 mixers for a reason lol. I'm no expert, but I always thought at least some hum came from the lack of a common ground between devices. Keeping the shield wires from all four devices joined together *should* eliminate that.

If not, you could quick/cheap test jury-rigging a connection between all four cases using eg a cheap spool of "bell" wire from Radio Shack. If that works, you could then make a more appealing connection by re-running this new ground wire chain alongside (twist-tied to) the audio wire rig.

Solder isn't necessary. You can just twist-braid the connections together as you would before soldering and test the circuit. If it works, then you can solder for permanence if you want. Only tip I'd offer is buy an extra set of resistors - they are cheap enough lol - in case your twisting breaks off a lead or three. Maybe even a set of 1k Ohm resistors to try substituting if the 10k reduces volume too much. Minimum order quantities and shipping one resistor will kill you lol.

Have fun . . . and PLEASE let us know what happens.

 

[xtc28]

Some or all noise will be reduced in the plan suggested by twoboxer. With the added ground as per his last post seems to be the way to go to prevent ALL Ground noise. Or just do what WE suggested to begin with ie: out to in to out to in and soforth.

 

[Twoboxer]

Yeah, I thought daisy-chaining the PC audio together was the simplest and maybe best approach when I first mentioned it. Then I realized that all upstream PCs have to be on in order to get headphone sound from PC #4. I thought that was less than ideal.

*IF* the patch cord works, he will hear sound from any PCs he has turned on atm.

 

[peng$ter]

Hey guys,

I haven't quite got around to try twoboxer's "ideal" solution yet, cuz I still haven't found time to get my arse down to radioshack.

But I told my colleague about what you guys suggested and he said he has tried that "daisy-chain" solution on just 2 PCs before. So the last 2 nights I rummaged around in my "cables & wires" drawer and found 3 M/M 3.5mm stereo cables.
Turns out this daisy-chaining solution does work !!

But,...

Just as I suspected, I got terrible ground noise. I had a ground-loop-isolator thingy lying around from old projects. It did it's job but I can still hear some ground noise. Maybe it's because I have 4-PCs daisy chained and it cannot completely isolate all the noise (or maybe it's just a cheapo isolator). Any suggestions on isolating noise?

Also I can't seem to get audio from 1 of my PCs. When I plug my external speaker set to it, I can hear audio fine. I think one of the intermediary PC is not mixing the signal from it's mic. I have to experiment some more to try to isolate the problem.

Anyway, I just thought I'd drop in to let ppl know what I've been upto before I get bogged down with my tinkering and forget to update this thread.

peng$ter

 

[xtc28]

Well then Im glad it worked for you. I would have to say cheapo isolator.