Tell me something

[fwb_1234 10+ year member]

OK. So.

What does the voltage on the signal matter?

I know higher is better, but is there really a difference in an 8V preout and a 5V preout?

How does this all work out when setting the gain/sensitivity.

Right now I have a stock HU and a LOC w/ sensitivity set on .9V.

If I get an eclipse HU (w/ 8V preout), to what should I set it, and will I notice a difference?

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[fwb_1234 10+ year member]

help?

 

[BoomBoomBoy 10+ year member]

Here is how it works. The higher the voltage of the signal, the lower the gain voltage you need to set on your amplifier. Remember, the goal is to have the cleanest S/N possible. It's always better to have a clean signal than to try and amplify a 'dirty' signal.//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[SeanDub 10+ year member]

Yeah, if I am thinking correctly basically the higher the preout voltage on the headunit the lower you can set the gain on the amp while still getting similar output. And the lower you can set the gain on the amp the lower the S/N ratio, as said by BoomBoomBoy above.

So is an 8v preout better than a 5v preout? Yes because theoretically you can set the gain on the amp lower and get the same output and have low S/N.

Is 8v or 5v better than 0.9v? Clearly.

 

[DRANGED 10+ year member]

He's pretty close to the truth. Most decks only put out the highest voltage at max volume, which basically is distortion. The higher the signal output the cleaner the signal you amps can receive which in turn your amps will run cooler and more efficiently. To set your gains on your amps, get a test tone disc and run it on repeat on a 50herts test tone and measure the output voltage A/C of your deck and then measure your voltage A/C of your amps and adjust your gains so that , that voltage is the same. So watch you meter as your adjusting you gains.

 

[fwb_1234 10+ year member]

What?

How do I do that?

 

[helotaxi 5,000+ posts]

The higher the signal output the cleaner the signal you amps can receive which in turn your amps will run cooler and more efficiently.

The voltage of the input signal has no bearing on the efficiency of the amp. Higher signal voltage will lower the system noise floor. Nothing more, nothing less. If you do not have noise problems with a .5V signal with the gains set to the point where you can get full output from the amp, then going to a higher signal voltage will gain you nothing.

To set your gains on your amps, get a test tone disc and run it on repeat on a 50herts test tone and measure the output voltage A/C of your deck and then measure your voltage A/C of your amps and adjust your gains so that , that voltage is the same. So watch you meter as your adjusting you gains.

WTF are you talking about?!? You have no idea how to set gains if you think that is how it works.

To the OP, read the gain setting tutorial in the amplifier forum.