Instruction: Given a question and the related document, and generate the answer to the question based on the information provided in the document.

Input:
Question: I'm running this mic for a car audio setup, and I already have a 12v supply as well as a 5v supply as options. What voltage should I supply to it? Thx
Document: I have this microphone set up outside and connected to the 'audio in' on a 7&#34; LCD TV. The sensitivity is good, it can pick up a conversation clearly out to about 40ft. I've left it out in the elements, rain and lots of sunshine and it continues to work well. Remember you'll need a power source and cable for it to work. A 12v DC power supply sold in the 'security cameras' section of Amazon will work as will any of the RCA video/power cables sold in that section.
For this reason, I only give it three stars. If you are a mind reader, or have used this product before, then you know it requires a 12v DC power supply. If you are a first time user, then you have to stumble upon this with lot's of research. No where in the description here on Amazon does it state this. I'm sure the seller gives the descriptions to Amazon so I can't really fault Amazon for this.For this reason, I only give it one star... but, the price gives back two so it nets a three star review.
Lost... How do you run with camera that already has mic? And how do you plug it in? Please help
Just as stated this is a sensitive audio pickup. I have it on the front porch and that makes the audio 'bassy', but I can hear a car coming anywhere on the block. I've run it through a CAT5e pair and there is some noise (to be expected on a 50' unbalanced cable run) but overall it is quite acceptable.
I got this mic to use for a baby monitor, and it has been working well! We can hear the baby really well, even when using a white noise machine. great product, especially for the price!
I attached this mic to my ACTi camera that I use as a baby monitor and it works better than I could have ever imagined. It works so well that I can hear my son breathing from across the room and can hear the clock ticking. Highly recommend this mic.
For the price, I'm happy with this.This came with large (hand sized) red security monitoring warning stickers (nicer than shown in the picture).For a dollar more, the same company makes a version with 2 DC power connections (male and female), that allows you to share the 12V connection with the camera if you wish;  I also purchased one of these versions.I'd recommend this for security system audio recording.
VideoSecu High Sensitive Audio Pickup Device External Amplified Tiny SpyGot it to use with a Swann system for the one audio channel it has. It works very well so far.
Surprisingly strong and clear audio when I mounted this in a antique metal outdoor incandescent light fixture reflector dome 125 feet from the Pyle PF200 60 watt amplifier. Mic power is from a 9 VDC wall wart. Cable is a combo of 100' of XLR cable and 25' of Belden 8723 2 pair twisted and shielded 22 ga signal cable with RCA connectors at each end of the run. The two pairs are combined to make 2 conductors. In building the cable I maintained the twists, soldered the splices, taped each conductor separately, covered each splice with heavy duty aluminum foil to maintain 100% coverage and finished with Scotch 33 Electrical tape.
It did not work at all. I am very disappointed because I expected it to enhance my surveillance capabilities on my cameras. Although I have not returned it I would advise you consider all options when it comes to this device. The price should have told me it was a fluke.
Answer: I'd say use a variable with it as the noise level at 12 volt is high