I'm trying to figure out the best way to connect a subwoofer to my PC. I have 2 monitor speakers (BX5a's) that attach via the stereo output of my soundcard on my Windows 7 PC. They attach to the green 3.5 mm output that has the picture of the headphones. I cannot figure out a good way to connect a subwoofer to this mix.
I know traditional subwoofers use the Red/Black Speaker wire, basically run speaker wire from a receiver/amplifier to the subwoofer, then speaker wire from subwoofer to speakers.
In this case the speakers are already connected via the aforementioned 3.5 mm "Green" output on the PC. How can I add a subwoofer to this mix?
Any and all helpful comments are appreciated, thanks!
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Are you using the on-board motherboard audio or a add on sound card? What sound card or what motherboard are you using? Some newer MBs have a subwoofer output.
And what is your subwoofer? Some subs can use just the stereo output and filter it to the subwoofer frequencies. Others are dedicated subs and use a sub output from a surround sound amp or maybe from a PC sub output.
The output from your soundcard is a stereo line level signal. It goes to the monitors which have built in amplifiers. Or one of them may contain a stereo amplifier which is used to power it's own speaker while the other speaker is connected to it via speaker cable, although it probably doesn't look like the red/black speaker wire you referred to.
Stereo speakers with a sub often have the amps built into the sub. Left, right and sub. The stereo line level signal from the soundcard goes to the sub, the left and right channels are amplified by the built in amps and sent to the left and right speakers via speaker wire. The low frequencies are separated inside the sub and amplified by the sub amp.
A sub could have just it's own amp. It'd require a line level signal from the soundcard containing just the sub frequencies. Your soundcard probably has spare outputs which could be used for that. Mine uses a single "stereo" output for centre channel and sub (similar to left and right channels but it's centre and sub instead).
If the sub doesn't need to be powered, it has no built in amp. It'd normally rely on being connected to an amplifier with a speaker output for a sub. Or maybe connected to one of the stereo speakers if one contains an amp for a sub. Yours don't. The soundcard's output can't be connected directly to a speaker (aside from headphones). It needs to be connected to an amplifier, even if that amplifier is inside the speaker box.
Thanks for the replies. I have an Asus P8Z77-VLK MOBO. The BX5a's are both independently powered. I currently have connected them to the PC using a dual XLR Male to 3.5 MM stereo cable.
I'm still not sure how to add a subwoofer to the mix. Assuming a powered subwoofer has RCA input/output, is the idea that I connect a 3.5 mm stereo to RCA cable from the PC to the inputs on the subwoofer and then use a RCA to dual XLR cable to run from the output of the subwoofer to the speakers? Would that work or am I still totally missing the boat here?
Thanks again for the replies!
Another possibility is to use a sub with only line level inputs and use y adapters to split the signal from the computer to both the sub and the speakers. That's less than optimal though.
Cool, thanks for the advice everyone!
It seems exceedingly difficult to find any subwoofers with line level inputs and outputs. Besides the one from MonoPrice I have found only 1 other that was in the $400+ range.
Are you aware of any other models? Admittedly the MonoPrice subwoofer looks like the one I will go with, but I hoped to at least find some other selections.
Thanks again for all the help.