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On Fri, 14 Oct 2005 22:08:14 -0500, (bob wald)
wrote:

10v..lol is too much 90% of amps cant handle it.

Just about any amp out there will handle 10V just fine - you just have
to turn down the input gain on the amplifier. Depending on the
particular amp, using 10V preouts might mean that you won't have a
very wide range of adjustment on the input gain before you start
clipping the amp, but it will work just fine, and you'll still be able
to drive the amp to its maximum power.

It helps if you understand the several stages of amplification that
take place in your car stereo system. I'll use a system with a CD
player as an example. The laser reads the digital information from
the disc, and the digital-to-analog converter changes it to a
low-voltage analog signal (somewhere around a few millivolts). Then,
the preamplifier in the head unit amplifies it to the preout voltage,
like 0.7V, 2V, 7V or whatever.

Then, the input gain control of the amplifier increases the voltage
even more, and feeds it to the amplification stage. The amplification
stage then does the final amplification, and gives you your 200W or
whatever the maximum is that the amp is designed to produce.

Let's do an example using some easy numbers. These numbers aren't
necessarily exactly what you'd find in an amplifier - I'm just picking
them to make the math easy:

Let's say that the amplification stage of your amp can only produce a
maximum of 200W, and to produce that 200W, it needs an input to the
amplification stage of 20V. Assume that your head unit can only put
out a maximum of 2V. To drive your amplifier to its max power, you
need to adjust the input gain on the amplifier to raise the 2V preout
voltage up to the 20V that the amplification stage needs. This is a
"gain factor" of 10.

If you use the same amp, but your head unit (or EQ) has 10V preouts,
you need to turn the amplifier input gain factor down to 2, so that
the 10V preout voltage gets increased to the 20V that the
amplification stage needs to provide its full 200W.

So, even with the 10V preouts, the amp is still only producing its
maximum 200W. In fact, since the amplification stage of the amp is
still seeing the same 20V that it saw before, it has no idea whether
you have 2V, 7V, or 10V preouts.

In conclusion, if you have high-voltage preouts, all that means is
that you're going to have to turn the amplifier input gain down so
that you keep the maximum voltage to the amplification stage constant.
Higher preout voltages won't let your amp produce any more clean power
than low-voltage preouts, and any increase in the signal-to-noise
ratio from using higher preout voltages is theoretical at best.

--
Scott Gardner

"After things go from bad to worse, the cycle will repeat itself."