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Preout voltage vs amplifier input sensitivity?
#409577 01/18/15 07:03 PM
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I have an AVR capable of max preout voltage of 6v rms. Nominal is stated as 1v rms. It will be connected to 3 external amplifier channels with an input sensitivity of 311mv for max output. They will be used for the left/center/right speakers. The AVR will handle the rest of the channels in the surround system.

Is the great difference between ouput voltage vs input sensitivity going to cause volume/trim issues between the onboard vs external powered speakers? I dont want to run the L/C/R preouts at -10 to match the onboard amplification.

Am I screwed up at how I'm thinking of this? confused

Re: Preout voltage vs amplifier input sensitivity?
AAAA #409579 01/18/15 07:27 PM
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I found This to be easy to understand for a simple explanation. I read the article back when I was buying my first home amp. Car amps have variable input gain so I had to study up a bit.

Last edited by Socketman; 01/18/15 07:28 PM.

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Re: Preout voltage vs amplifier input sensitivity?
AAAA #409581 01/18/15 07:59 PM
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Thanks for the link!

Ok, I see the formula used equates to a voltage gain of 35.49 for the external amps. Seems really high. The manual states a max dc offset of 15mv. Whatever that means.

148w into 8 ohms. 285 into 4 ohms. From .311v input. Crazy.


According to the article this setup might be on the verge of too much of a good thing. I may be approaching my AVR preamp noise floor to make the external amp work out. How does anyone elses setup compare?

Last edited by Serenity_Now; 01/18/15 08:03 PM.
Re: Preout voltage vs amplifier input sensitivity?
AAAA #409583 01/18/15 08:19 PM
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Yes that is quite high and may cause the preamp to introduce noise into the signal, especially with very sensitive speakers.
Another good read.






Last edited by Socketman; 01/18/15 08:21 PM.

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Re: Preout voltage vs amplifier input sensitivity?
AAAA #409592 01/18/15 11:20 PM
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Ok, I'm not so concerned now after the 2nd article. Seems the nominal 1V output is perfectly fine for the input sensitivity. I just got hung up on the 6v max figure. That must be with the trim level at +10 or so. In any case, I wont know until I try.

Thanks for the info. smile

Re: Preout voltage vs amplifier input sensitivity?
AAAA #409604 01/19/15 03:24 AM
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Originally Posted By: Serenity_Now
... In any case, I wont know until I try.

Thanks for the info. smile

Hey, at least you know you don't need to turn it up to 11 to blow the roof off. smile


Fred

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Blujays1: Spending Fred's money one bottle at a time, no two... Oh crap!
Re: Preout voltage vs amplifier input sensitivity?
AAAA #409617 01/19/15 03:26 PM
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Let us know how it goes. Hopefully they will maintain an equal volume level as things get turned up.


DOG is GOD spelled backwards.
What others think of me is none of my business.
M80 V3 MY GLOSS Cherry

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