Hi
Can anyone help please.
I need something (if there is such a thing) that I can listen to my audacity recording from my computer and play along on my keyboard with it without having to wear two sets of headphones (physically impossible? lol)
Like some thing so i can plug two devices into one set of headphones… have I explained that properly?
Thanks…
That’s a built-in service that Audacity has called Overdubbing. If you set up for that, Audacity will play your old tracks (as many as you select) into your headphones – or speaker system at the same time you can play along and record that on a fresh, new track under all the old ones.
http://manual.audacityteam.org/o/man/tutorial_recording_multi_track_overdubs.html
But.
As a rule, you can’t hear yourself at the same time. I called doing that “Perfect Overdubbing.” To get perfect overdubbing usually requires special hardware or expensive software. Any time you send your voice into the computer and bring it back out again, it will come out late. Yes, this messes up playing with yourself and it’s permanent.
I wrote about three different ways to get around it and they all require special hardware to run the headphones. All three provide a mix of old and new. For example:
http://www.kozco.com/tech/audacity/pix/peaveyUCA202Lenovo.jpg
Windows people have the option of WASAPI software about which I know very little, but it’s supposed to give better of management of sound inside the computer.
You can only do Overdubbing on speakers if you’re playing an instrument with a pickup or a sound generator (keyboard). If you’re going to sing, good, sealed headphones are required.
http://kozco.com/tech/audacity/wynonna2.jpg
Koz
No nothing that complicated… i just wanna listen to two audio outputs the same time thru one set of headphones. 
OIC.
OK. One of these “Y” cables:
http://www.radioshack.com/product/index.jsp?productId=2272476
Or equivalent.
Two of these, one to the computer and one to the keyboard.
http://www.kozco.com/tech/audacity/pix/stereoJumper.jpg
Buy from anybody. Connect one to each branch of the “Y” cable.
One of these to connect the “Y” cable to your headphones.
http://www.radioshack.com/product/index.jsp?productId=2102697&znt_campaign=Category_CMS&znt_source=CAT&znt_medium=RSCOM&znt_content=CT2032231
Several people make these. It connects two male plugs together.
Some systems put up with this and some don’t.
If it sounds fuzzy when you do that, you may have to use an actual mixer.
Koz
Many sound cards (but certainly not all) can do the mixing you want internally. You would connect the output of your keyboard to the “line in” connection on your computer (usually blue) and connect your headphones to the computer normally. Then find the “mixer control panel” for the headphone/line out and if you are lucky there will be sliders for both “line in” and for computer sound output. Describing exactly how to find these controls is difficult as it varies wildly depending on what operating systems you have, and what sound hardware you have.
If your sound card doesn’t have this capability the best answer is to buy a small mixer like the Peavey PV6 that is very popular among users of this forum. (There a plenty of other options as well, looking at the fullcompass website for mixers I found at least a dozen products under $100 that would fit the bill, but afraid I don’t have any direct experience with any of them). You will still need suitable adapter cables if you go this route. At the very least a stereo mini phone to dual RCA cable to connect the computer to the mixer such as http://www.radioshack.com/product/index.jsp?productId=3452165, and likely possibly a pair of RCA-Phono to 1/4"Phone plug adapters like http://www.amazon.com/Hosa-Cable-GPR101-Inch-Adaptor/dp/B000068O3S. You may need a similar setup to connector keyboard to the mixer, or you might just need a 1/4" phone cable, depending on the connections available on your keyboard. Finally you will probably need a 1/4" stereo to 1/8" stereo adapter (Your headphones probably came with one of these if you can find it…).
I would be a bit cautious about directly connecting the two headphone outputs directly together as Koz suggests. The odds are high that it will be just fine, but in the small chance that both your keyboard and your computer actually have low-output-impedance, designed-to-drive-8-ohms amplifiers in them then you could potentially overheat and/or damage one, the other or both. (It’s far
more likely that the keyboard’s output will simply over power the computer and you won’t be able to get an acceptable balance between the two.)
Excellent… Thank you very much
… I will order these straight away.
Thanks again
Many sound cards (but certainly not all) can do the mixing you want internally.
But most not in real time. This is a serious problem with people overdubbing.
“How come my voice has an echo or is delayed in my headphones.”
The three hardware solutions in the overdubbing tutorial were reviewed as an example of how to get around this problem.
http://manual.audacityteam.org/o/man/tutorial_recording_multi_track_overdubs.html
“Generally, purpose-built hardware is needed to hear your live recording without unacceptable playthrough latency - without that hardware you will hear what you are recording too late.”
Koz
Good grief, this is complicated eh.
Best I just chuck the other members of the house out and live on my own, I wouldn’t need headphones then lol.
True. But that only works if you never intend to sing or have a live microphone. Then headphones are required. Koz
It only sounds complicated because there’s lots of ways to skin this particular cat.
Some cards will add a delay in mixing the analog input with the computer sound, some don’t. For those that do have a delay, the delay is usually pretty small and may, or may not, be an issue in your keyboard playing.
Another option you should check is that many keyboards have “accessory” or “line” or “auxiliary” inputs. If yours does then you could probably connect the computer’s sound output to that and then just plug your phones into the keyboard.