5punk

I have 2 PCs at home and I'd like to use the same set of speakers for them both, they're only 2.1 so only one 3.5 jack to worry about. What I'm after is the opposite of a headphone splitter I suppose, any ideas where I can get something like that? Ideally with a switch.

My current solution involves extension cables taped to the desk top for easy plug changing. But I'd like something more elegant without being too expensive.

/edit
I've just realised I could involve gender changers, but that's still a bit messy. Is there a sound quality concern with wiring up two sound outputs to a single set of speakers?

Summat called a reverse y adapter lets you do it on the cheap. It just turns the speaker cable into 2 separate inputs.



You could also get a 3.5mm to 3.5mm cable and run it from one pc to the other and go from line out to line in to run the sound through one pc alone. If you set the line in sound levels well, then you'll be able to control everything from your speakers or desktop volume control.

The sound quality with both these methods should suffer no noticeable loss.

A fancy kvm would allow you to share mouse, keyboard, monitors and speakers for each pc, but that's lots of wires and money.

Something from here: http://www.maplin.co.uk/Search.aspx?menuno=84539

The cable pete suggested is going to cause distortion unless both sound sources have infinite impedance (unlikely).

Edit, if you want to have both sound sources going at the same time, you need a mixer. You can't just link the two sources in parallel.

If the cable's really long it will. I've used a 3.5mm to 3.5mm connector about 5 metres long before and suffered no noticeable distortion, or do you mean the splitter? they're a couple inches long and really don't do much either.

HereComesPete wrote:If the cable's really long it will. I've used a 3.5mm to 3.5mm connector about 5 metres long before and suffered no noticeable distortion, or do you mean the splitter? they're a couple inches long and really don't do much either.

I mean the actual reverse-splitter, in the picture.

Ideal signal sources (i.e. computer speaker output) have zero output impedance. This allows you to draw a theoretical infinite current to power anything. In reality they are low, not zero - and are current limited. For simplicities sake lets say it is the equivalent of a 10 Ohms resister (with no reactance)

You've got a circuit diagram of this:



Lets say Signal 1 is peak-to-peak 1v, and signal 2 is peak-to-peak 2v. You have a potential difference of 1v between the two sources which HAS to be over in the internal resistance of the two sources (the 10 Ohm resisters). Forcing a potential difference of 0.5v over the internal circuitry of each sound source is going to fuck with the sound, not to mention the sound card.

In order to sum two sources, you must use a summing amplifier, simple transistor ones will do. These have (ideally) infinite input impedance (so they draw no current) and zero output impedance (so you can drive anything).

See, I've got the opposite problem - speakers and headphones and I can't be arsed grubbing about behind my PC to switch them over.

Dog Pants wrote:See, I've got the opposite problem - speakers and headphones and I can't be arsed grubbing about behind my PC to switch them over.

Buy speakers with a headphone/microphone port on the front?

Grimmie wrote: Buy speakers with a headphone/microphone port on the front?

Replacing my rather nice speakers just because they don't have a jack on the front is a bit excessive.

Does your sound card not have a switch to headphones buttan in it's control console??

Mrh? Dunno, but unless the button magically unplugs my speakers and plugs in the headphones it ain't going to work. I think rigging my case jack to the sound card might work, other than that I can live with it for the amount of times I get to use my headset these days.

Dog Pants wrote:See, I've got the opposite problem - speakers and headphones and I can't be arsed grubbing about behind my PC to switch them over.

I solve this problem by hooking my speakers up with an optical connection.

Thanks for the info. I think I'll try a reverse Y connector first and if I get bad sound go for one of those stereo switching boxes. I don't want to hear sounds from both PCs at the same time, mostly one will be off while the other on. Ubuntu on my lower powered PC is working out better and better these days, it's really coming along nicely.

DIY Solution #1

Get a 3 way switch, as the cables will be stereo, use an 3 Pole (9 pin) 3PDT switch, like so:




Rapid Electronic's part: 75-0092 (Linky)

Basically acts as an OR switch, only one will be "on" (center position is "off"), and it'll be a complete swap seeing as stereo lines have 3 cables per jack (Left-Right-Earth).

You can mount it in a small box, use 3 jack sockets: 2 female (input) 1 male (out) I think, so you can just plug in the cables to it as you need.

Dead easy, dead simple, would be effective for your needs as like you say, you've only got 1 cable coming from each computer.

use a hammer?

Dog Pants wrote:See, I've got the opposite problem - speakers and headphones and I can't be arsed grubbing about behind my PC to switch them over.

I had this problem too, and just have a very small splitter plugged into the soundcard, so my headset sits on top of the case when I'm using the speakers, and they have their own power switch so I can turn them off when I want to use the headset. Works for me.