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Richard Kuschel
 
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Default input sensivity / headroom on amplifier


hi

i've a question about the input sensitivity of the amplifier electrovoice
P3000

data sheet EvP3000:

www.electrovoice.com/electrovoice/EVfiles.nsf/lookup/P3000/$File/p3000-eds.p
df
( ..../p3000-eds.pdf )


input sensitivity=0dbu (0,775 Vrms)
maximum input level=+20 dbu (7,75 Vrms)

i have two meter before the amplifier input:
-Rms Vu meter that display 0dbVU whit a 1 khz sine @ 0 dbu
(max display=+3dbVU)
-Peak led meter that display 0db whit a 1 khz sine @ 0 dbu
(max display=+24db)

i work in live (much peak and not much rms), so i wish to put a
maximizer/compressor @ L/R, after the maximizer a
RMS limiter (set@0 dbu), and after all a peak limiter (set@+19 dbu)....
.... al before the meter (Vu and Peak), so i can keep under control in every
time the signal that go to the EvP3000, a signal where the rms don't go up
0dbVu and peak don't go up +19db.

what did you think about this?
is a correct way to take the full 1200Wrms @4ohm from the Ev3000
without distorsion, or a stupid way to crash all the system?

thank's a lot, and excuse my very bad english.

marco



I was unable to access the page, but this is what your specifications mean.

The amplifier is capable of putting out its rated power with a 0.775 volt
signal (0dBu) You will need to turn down the input attenuation on the of the
power amp if the rest of your system is capable of putting out +19dBu

Very Important!!! This does not adjust the power of the amplifier, only the
amount of voltage necessary to drive the amplifier to full output


The amplifier should be set so that every component in your system clips at the
same time.

In other words, when your preamp input clips, the channel should clip, the
output from your board should clip and the power amp should hit clipping.

Now put in your limiter just before the power amp and set it so that it kicks
in just before the power amp clips, preventing the power amp from clipping.

Turn down input gain on the board just a little bit the board a little bit and
you will be just fine.

If you are looking for more RMS output, set the RMS compressor closer to the
value of the peak limiter. Try +6dbu instead of 0dBu. and make up the gain
reduction from the compresssor with the output level of the compressor.

Richard H. Kuschel
"I canna change the law of physics."-----Scotty