How do i know how much voltage is coming out the RCA's

finkle636 · Post by **finkle636** » Thu Nov 06, 2008 6:44 pm

How do i know how much voltage is coming out the RCA's ?

If my head unit puts out 4v and i increase it with a line driver that puts out 8 volts will i end up with 8 or 12?

Or can i measure it with a meter somehow ?

deathcloud · Post by **deathcloud** » Thu Nov 06, 2008 6:54 pm

You have to go and get a Digital Multimeter

http://www.amazon.com/gp/product/B0002YFD1K

With this you hold one of the probes on the tip of the RCA (thing that looks like a rounded point) and then hold the other probe to the shield (the thing that looks like a metal sourround that shields/protects the rounded point)

When you do this, it shows you the voltage that the RCA is producing. There is a whole thread containing how to set gains ect if you search and ive been in a few threads of how to do it. Maka had a great write up somewhere if you do a little search. Stipud is the main genious though props to him.

***EDIT***

Found the good thread

http://phoenixphorum.com/problem-x200-4-vt7570-25.html

When I had the volume up on my headunit CDA-9855 and my dads Pioneer 6000UB when measuring the RCAs that run to the back not hooked up to the line driver it always reads 1 and never got higher even at 3/4 volume. Is that bad? I thought for sure his would read at least 4 volts but i dunno. Its measuring after the line driver when it actually goes up.

finkle636 · Post by **finkle636** » Thu Nov 06, 2008 7:03 pm

Does the voltage remain the same for all volume levels?

It's DC current, yes?

What should I be aiming for going into my amp (8v max limit i think on the RSD)

finkle636 · Post by **finkle636** » Thu Nov 06, 2008 7:41 pm

I have read the post you sent the link to, makes sense

Post by **stipud** » Fri Nov 07, 2008 7:40 am

finkle636 wrote:Does the voltage remain the same for all volume levels?

It's DC current, yes?

What should I be aiming for going into my amp (8v max limit i think on the RSD)

No, it's A/C current, and it changes depending on volume. Every 3 decibels less is half the power... so at max volume you'd push, say, 8 volts... 3dB down it would be 4, 3dB down from that it would be 2, etc.

So just play a 50Hz test tone (since that is the frequency of your A/C outlets in the UK), turn the volume to 3/4 on your headunit, and then measure the RCAs with the + on the RCA pole and the - on the RCA shield. Easy!