Contour Enthusiasts Group Archives Forums Modifications Audio Myth or not?

Here's a question for you car audio fanatics:
What is your opion about high voltage pre outs on a deck??? People say that the higher voltage pre out helps alot, but then other people say that it's just mumbo jumbo!!!
So what do you guys say about this???

i've heard high voltage outputs are very helpful too - i know you need to adjust to amp's levels according to the voltage of the signal.. but i dont know why. im just as interested in knowing the answer as you are, so i guess this is just an extended

BUMP

higher voltage pre-outs are better in complex systems...in a simple h.u. 1 amp setup, you might not notice the difference, but with multiple lines running, they do offer better signal transfer, and they are much easier for your amp to deal with...To try to paint a picture of this, imagine a slope from low to high...with, say a 1.8V output, your slope is very steep, the amp not having much room between zero power and full power...with a 4 or 5V. output, the slope is much more gentle...Keeps your amps cooler and with you longer....

HTH

Hi-volt pre-outs are primarily for eliminating noise from the system with a "stronger" signal with less noise making it to the amp (higher S/N ratio).

I don't believe it has any effect on the amp's life or its heat dissipation. Those are traits inherent to the amp. It'll amplify noise just as well as it will amplify the signal. It doesn't know the difference.

I agree that they eliminate noise (see previous post), but they also give more headroom...thus the gain settings...setting the amp's gain at 1.8V with a 5V pre-out would waste most of the amp's available power...
KnuKoncepts explained this very well in a thread a couple weeks ago...pretty much the amp will be running at full power when the input voltage and gain settings match...if they are different, your amp is gonna be off kilter..(Gawd, I love the phrase "off-kilter") :p

It depends greatly on the amp that you are using. 4v outputs with an amp with only a 2v max input would be automatically driving the amp into clipping. That is why line drivers are virtually useless unless you have an amp with a very high input voltage.

Actually, you've got it reversed.

As long as the HU can produce at least the minimum input of the amp, the amp will be able to produce its maximum output.

For example, let's say your HU only puts out 2V and your amp's input range is 1-4V. Therefore, you set the gain on your amp to 2V and your amp will produce its full potential.

If you set your amp's gain to 1V, like Dave said, you'd be driving it into clipping and risk damaging your equipment.

The gain setting on the amp is ONLY to match the voltage between the HU and the amp. I believe you're referring to the post where Knu was explaining how to set the gains by ear without knowing the actual voltages.

So there! :p

The higher the output V on a HU( w/an amp with equal or greater input V ) can yield a more precise and sensitive adjustment - but yeah your only trying to match the two in the long run ( since all or most amps/HUs are different ), higher Vs just give you more headroom to work with.

My question is why hasn't anybody ( company ) made a set of balanced outputs/inputs for hardware?! Is that what alpine has done? I have a ALP 4V HU to ALP V12 amp that is switchable nom/4V but is the HU always pumping out 4Vs?..anyway they should just make everything digital coaxial RCA so theres no "levels/clipping" to worry about~ yah know!

you caught me being wrong on that one...Thanks for not bi+ch-slapping me into last week for it!

No worries. I figured it was just a typo or something.