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trunks9_us
09-06-2007, 10:59 PM
How can i tell how much preamp voltage my hu is putting out when i have it up at certain volume so i know what to go over and not. My hu says its 2 volts but i want to know if it is really putting out 2 volts or 1 volt it would be a big help if someone can guide me to a tool or somthing.

And plz do not say get a hu with high preamp outs cause i am using a zapco sldin-t.f line driver to multiply times 4 then a slb-u to multiply it again. i just want to get max voltage to my amp that i can get so i dont have to turn up my gain hardly at all to get my best sq for my amp. I am using a kenwood kvt-719dvd. My zapco amp can take up to 16volts input so this is why i am asking.

trunks9_us
09-07-2007, 12:29 PM
can anyone not answer this simply question its either theres something to use or not.

ShakesAllDay
09-07-2007, 12:40 PM
I've wondered how to measure pre-amp voltage, as well.

JT1979
09-07-2007, 12:40 PM
Use a volt meter. You will have to have RCA's hooked up and touch the red to the prong out of RCA's and then touch the black to the outside of the RCA's. I have never done this, but it seems as it should work.

Sry if it dont work, but this is all I can think to do

adam71
09-07-2007, 12:57 PM
How can i tell how much preamp voltage my hu is putting out when i have it up at certain volume so i know what to go over and not. My hu says its 2 volts but i want to know if it is really putting out 2 volts or 1 volt it would be a big help if someone can guide me to a tool or somthing.

And plz do not say get a hu with high preamp outs cause i am using a zapco sldin-t.f line driver to multiply times 4 then a slb-u to multiply it again. i just want to get max voltage to my amp that i can get so i dont have to turn up my gain hardly at all to get my best sq for my amp. I am using a kenwood kvt-719dvd. My zapco amp can take up to 16volts input so this is why i am asking.

They handle 16 volts "balanced" voltage right?? And your line driver is the one that takes an unbalanced signal from a headunit and turns it into the balanced and sends it to the amp?? If this is so then why worry about the actual voltage output of your head unit?? Your amp will get the voltage it needs regardless. I guarantee your deck will put out 2 volts but most likely only at full volume. Knowing the voltage of your deck isn't going to help you out anyway. If this is a huge concern of yours then you ARE going to have to get a higher voltage head unit. There is no way around that. Also, I highly doubt lowering the gains on those Zapco amps from say 1/4 turn down to 1/8 turn will be an audible difference.

My advice to you is to not worry about it. It'll be fine.

kross
09-08-2007, 07:38 AM
The advertised preamp voltage is the maximum voltage possible. To produce it, you need a test tone recorded at 0dB, and play it at full volume. Then measure the output with a DMM.

ShakesAllDay
09-08-2007, 02:31 PM
I tried using my DMM to measure my RCA voltage.

* please note: I'm not an expert DMM'er.

Method:

- had the DMM set to AC volts @200
- I put a 40hz 0db test tone on (testing sub pre-amp) @ 30/35 volume (Alpine 9883)
- I put the pos. test lead on the inner plug, and the neg. test lead on the outer jacket

I could never get any volts to register... I even tried DC volts... nothing.

Please help.

Sunfire01
09-08-2007, 04:13 PM
Maybe I'll try this when I get my PG line driver fixed. I have a high end multimeter that should tell me something!

trunks9_us
09-09-2007, 12:48 PM
plz do i would like to know how much my kenwood is.

Atimm693
09-09-2007, 02:45 PM
Multiplying your HUs voltage over and over again is going to have the same affect of turning up the gain to compensate for a lower voltage. Remember you can only multiply a signal to a certain point until the once clean signal is clipped.

Id say sell the line driver and the other thing and save the money, unless you really need the line driver for multiple amps.

luvinthebass
09-12-2007, 02:42 AM
I tried using my DMM to measure my RCA voltage.

* please note: I'm not an expert DMM'er.

Method:

- had the DMM set to AC volts @200
- I put a 40hz 0db test tone on (testing sub pre-amp) @ 30/35 volume (Alpine 9883)
- I put the pos. test lead on the inner plug, and the neg. test lead on the outer jacket

I could never get any volts to register... I even tried DC volts... nothing.

Please help.

unplug the rca's from the amp and do your reading from there to get the voltage, not when they are connected lol...