Building Your Own KVM Switch...With Audio Connectors? 80
Michael B asks: "I recently bought an 8 port KVM to switch between various workstations and servers at home, and I'm realizing what I can't switch is audio! I've seen 4 port audio/video type switches (for things like switching between video console systems) but this doesn't address more than 4 ports and having the adding RCA/S-Video is a waste. I've thought of building one from scratch using Radio Shack parts, but can't find any info, such as a schematic, online. Does anyone have any ideas or sources of info for this one? Belkin seems to make a 4 port KVM with audio, which would be nice, but I need more than 4 ports. Thanks for any help!" After a bit of digging, I found this monster, which does 8-port KVM and audio, but that weighs in at a hefty $500USD, which is rather expensive. Has anyone managed to find schematics to such switchers so that folks, who aren't afraid of soldering irons, can build their own?
cheaper solution (Score:5, Informative)
Re:cheaper solution (Score:5, Informative)
Re:cheaper solution (Score:1)
Re:cheaper solution (Score:2)
The added benefit here is that you can keep the audio going on one machine while switching to the other. If you're listening to MP3s this is nice. Or, if you're waiting for a really long process to finish and it has a sound queue, then you can leave that audio channel open.
I agree with parent poster, this'd likely be a better option for ya.
Re:cheaper solution (Score:4, Insightful)
Re:cheaper solution (Score:2)
James
PS for really cheap people with 2 computers use that input on your sound card
the easy way (Score:2)
Re:the easy way - true story (Score:4, Funny)
Re:the easy way - true story (Score:2)
No, it's because they're a retail outlet and most of their business is appliances. They employ people based on retail experience only and it's a lucky coincidence if any of their staff can even recognise a capacitor.
Re:the easy way - true story (Score:3, Informative)
Re:the easy way - true story (Score:2)
Re:the easy way (Score:3, Funny)
Re:the easy way (Score:5, Funny)
Mix instead? (Score:5, Interesting)
Re:Mix instead? (Score:2)
Stupid Idea (Score:1)
Re:Stupid Idea (Score:1)
I tried this before with a 4 port kvm and 2 port kvm with horrible results...
Although it looks like some of the higher end kvm's can be daisy chained through a special connector i don't think even the highest end ones will work as suggested in parent.
Here's an idea (Score:5, Informative)
Each of the relays would gate the respective sound signals onto a common bus. Use a double pole relay for stereo. 2N2222 (npn) and 2N2907 (pnp) are available from Fairchild through Digikey in TO-92 packages and would be a good choice for a relay driver.
Likewise, an Omron TX2-5V is a reasonably priced DPDT telecom relay with a 5v coil, also available from Digikey.
Re:Here's an idea (Score:3, Informative)
sometimes simpler is better (Score:1)
If you're looking for higher end sound (music, et all) then you're probably better off dropping the $5C.
I am waitng for the telepathic models to come out. (Score:1, Troll)
USB KVM (Score:4, Insightful)
I haven't tried this myself, but it seems like it should work.
Re:USB KVM (Score:3, Informative)
Re:USB KVM (Score:3, Informative)
I know how KVMs work, or at least how they are supposed to work
Re:USB KVM (Score:1, Interesting)
(I say "in theory" because I just had to reboot windows to see a new mouse.)
Re:USB KVM (Score:2)
Not much you could expect the system to do if the sound device disappears while sound is playing other than to abort. So much for flipping to another machine for a moment and expecting the MP3 to still be playing when you flip back.
Alternative (Score:2)
KVM (Score:3, Funny)
get a mixer. there is probably little reason you'd want to play music on more than one computer at a time, so just get a mixer and put them all into the mixer and out the speakers right in front of you.
Don't switch audio -- mix it. (Score:3, Informative)
Re:Don't switch audio -- mix it. (Score:2)
I want to be able to have stereo inputs 1 to 6 and mix those into either of stereo outputs A or B, output C might be useful too. If anyone has any suggestions.....?
I'm quite happy to build my own, I just don't have the knowledge to design it or the time to acquire that knwledge, but I can probably build it.
Read Piquan's post above (Score:2)
You can build mixers pretty easily using op-amps, and Forrest Mims' "Engineer's Notebook" has quite a few useful designs.
Where to get it? Rat Shack, although these days it's often not stocked (just like their 150-2160 UHF-only TV antennna grumble grumble)... RS is going downhill.
RS is definately not the optimum place to get electronic components, but when you need something fast and you aren't buying that much, it's quick. Digi-Key is far better, but keep in mind that DK sucks for small o
Consolodate (Score:1)
Get thee ass to a radio shaK (Score:2)
Seperate switch (Score:2, Interesting)
Re:Seperate switch (Formatted right) (Score:2, Informative)
I built a 2X2 for switching two computers to either earphones or speakers.
Two DPDT switches, one controls input, one controls output.
(ASCII art deleted because Slashdot can't deal with it.)
1 and 2 are connected together, i and o are inputs and outputs, left and right. Tie all grounds together, switch L+R. I guess doing that could cause a ground loop hum, but it hasn't caused a problem for me. There isn'
Probably you don't want that. (Score:2)
Any recomendations for mixers? (Score:2, Interesting)
Re:Any recomendations for mixers? (Score:5, Informative)
Re:Any recomendations for mixers? (Score:2, Informative)
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewIt
http://cgi.ebay.com/w
on the high end: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ite
DJ Aaron Z
Re:Any recomendations for mixers? (Score:1)
DG
Not too hard... (Score:3, Informative)
If you care about sound quality or having the device look nice, just get a desktop mixer. That's perfect for having multiple computers driving a single stereo.
Re:Not too hard... (Score:2)
Here's an idea ... (Score:2)
Belkin SOHO (Score:2, Informative)
_
Re:Belkin SOHO (Score:2)
Worse, they are riddled with mouse control bugs, and its noticably annoying when using Linux. You need to use the mouse while switching, or you'll lose mouse scroll or any mouse control, or freak out the xwindows session. (In which case, you need to do an ctrl-
Re: (Score:2)
Re:Belkin SOHO (Score:2)
Its not the motherboard or the power supply. It has to do with the fact that the SOHO is overpriced but cheap assed in quality. Instead of storing and maintaining every mouse setting before hopping to the next machine, it feeds a mouse reset code when it hops back to the old machine. This freaks out any Xwindows version besides the latest, and as one AC said, its no good for wheel mice. I'll sooner chuck the SOHO than my wheelmouse.
2 KVMs (Score:2)
mixer (Score:4, Informative)
CCTV (Score:1)
seporate audio switch, who knows
just an idea
Audio, Video, Keyboard and Mouse Switching (Score:2, Informative)
Just how much bandwidth is in a video signal? Well, if you have a screen of 1024x7
1600*1200*75 = 144 MegaHertz. (Score:2)
19 inch CRT monitors with a 1600 x 1200 resolution cost as little as $225, so that resolution is becoming a standard.
It is a big technical achievement to switch 1600 x 1200 resolution without video degradation. IO Gear [iogear.com] does
Note that IO Gear plays games with cables. (Score:2)
Also, the keyboard controls for switching may not be well considered.
IO Gear does seem to be the best for video quality.
Re:Audio, Video, Keyboard and Mouse Switching (Score:1)
With regards to relays, this statement is simply wrong. A good quality relay is infinitely superior to any electronic switch. For instance, reed relays are available which will switch from DC up to microwave frequencys at useable power levels and have 'on' resistance values which are magnitudes better than an elctronic switch. Bear in mind that
Cheap Mixing with Daisy chain (Score:2, Interesting)
Re:Cheap Mixing with Daisy chain (Score:1)
Found a 2-port KVM switch with audio!! (Score:4, Informative)
It's 2 ports, supports audio & is only about 90$.
Do it in software (Score:4, Informative)
Machine you work on:
cat
Machine you plug your speakers in:
nc -l -p 48050 >
You don't need 8 port audio switching (Score:3, Interesting)
It just doesn't seem worth the effort to try to find a solution to this "problem" when it doesn't even seem to be much of a problem. But you're certainly free to spend your free time doing whatever you want, including trying to hack together your own KVM switch.
Good luck.
Re:You don't need 8 port audio switching (Score:1)
Did you read the question? He said that he wanted the audio to run through the KVM switch too. This would imply that the only sounds that he'd be hearing would be coming from the one machine that he's switched to currently--just like the only video that he sees is the video
Just get more speakers (Score:1)
I built my own passive selector using .... (Score:2, Informative)
3x female 1/8" stereo jacks
4x female RCA mono jacks
4x SP/DT slide switches (3/16" x 1/2")
2' jumper wire
1x plastic electrical junction box
1x clear plastic picture cover from picture frame. (3"X5")
First 4 parts are available from RadioShack for a total less than $10. The junction box is available at Lowe's for $1.66. The picture cover you can get with any cheap picture frame.
step 1: lay the junction box upside down on a piece of paper and trace. Cut out the outline.
step 2: lay out the jack
Don't build a switch, build a passive mixer (Score:2)
I actually just daisy chain the inputs of my PCs. Take the line out of one. Plug it into the line in of the
Mixer is the way to go. (Score:1)