Author Options:

VU meters between PC and external speakers Answered

Hope someone can help. I want to place two analog VU meters (L and R) in-line with my external PC speakers. I want them to be between the PC tower sound card output and the speakers themselves (1/8" mini jack), so the speaker volume controls don't affect the meters. I'm trying to get the truest reading from the sound output level coming from my PC and video editing program, without building some monstrosity. I'm planning to build a small box to house the meters, so I just need help with the actual wiring between the mini jacks and the VU meter leads. Can anyone help with how to wire this with instructions or a wiring diagram?



8 years ago

I'm guessing that the VU meters are, essentially, voltmeters. If so, they would bridge between signal and ground for each channel. On a tip/ring/sleeve "phone connector" such as the ones you show in your diagram , sleeve is ground, tip is one channel and ring is the other.

Depending on the meters, you may also need a resistance in line with them... or you may need an amplifier driving them. (Actually, unless they already have suitable electronics, I'd suggest an op-amp to minimize the load they place on the signal wires, with the amplification of that op-amp set to generate results in the appropriate range for the meter.)

Hope that helps.

Simpler solution: Get a junker cassette deck with VU meters. Feed from sound card to Record In, and from Play Out to the speakers. Put the deck in record-pause mode. Use the recording level controls to set the deck's VU meters to the appropriate range, then set speaker volume appropriately. This will also leave you ready to actually record your PC's audio output at a moment's notice.

(I actually have a small stereo system hooked into the loop, so I can also easily record from tapes to the PC. I'm slowly dubbing off some of my rarer recordings. Eventually I plan to transfer my grandfather's old 78's as well.)


Answer 8 years ago

Hi Ork, Thanks for the quick reply. I probably should have mentioned that the speakers are AC powered to the right speaker that plugs into the wall outlet, and then there is a minijack cable that goes from the right speaker to the left speaker to power that one. But it sounds like you're saying that once I determine which minijack leads coming from the PC are the ground/left/right, I should be able to solder them properly onto the VU meter and then continue them to the OUTPUT minijack receptacle on the VU housing to plug the speakers into. Is that right?
Also, one confirmation: Are you saying that the VU is essentially a volt meter and gets wired to the ground and the respective left/right lead?