# Are preout signals all standard?

Discussion in 'Beginners, General Questions' started by Kenneth Harden, Dec 8, 2003.

1. ### Kenneth Harden Screenwriter

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As in, is 0 gain on a preamp a cartain voltage on ALL preamps?

I am asking because I am confused how a hower amp know what level to play (as in, is no gain on a preamp always a given voltage, which is full-power on all amps?)

I know this doesn't effect sould levels, just relative output on a given amp.

To clarify. Is the preout output voltages the same at a given volume level (1/4, 1/2, full volume) on all preamps?

Thanks!

2. ### Chu Gai Lead Actor

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No, it varies. And to further complicate matters a bit, you'll find that the voltage necessary for a particular amp to reach its rated power also varies. So if your preamp at a given setting is putting out some voltage, let's say 3 volts and your amp will put out its rated power at 2.5 volts, then your preamp can drive your amp into clipping. Fun, huh?

3. ### Cees Alons Moderator Moderator

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Although some standards are defined, the short answer is: no. Different pre-amps may have different output voltage levels at the same settings and different power amps may have different overall gain at equal settings.
And sources may be different: the "normal" (whatever this means) level on one CD or DVD doesn't have to be the same as on another - and it seldom is.

Cees

PS;
Ha! Great minds... etc.! Parallel posting.
C.

4. ### Kenneth Harden Screenwriter

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Though this is the 'n00b' forum, let's take it to the next level:

How do you work with that to make sure your volume control can 'see' the entire amp? Do good preamps let you adjust the voltage output to make 1/2 volume on the preamp act as 1/2 volume on the amp?

5. ### Cees Alons Moderator Moderator

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Kenneth,

Yes, good pre-amps have dials as have power amps.
The general rule is: set the first (pre-amp) dial as loud as you can without either causing distortion or having to set the next one at an idiotic low position. Then turn it back a bit. Then use the last one (on the power amp) to set the sound to your liking.

If you happen to have an extremely loud DVD- or CD track, dim it on the pre (because it may again cause distortion of the signal). And if you still have enough room then on the power amp dial, you could leave the pre-amp volume in that position.

Cees

6. ### Chu Gai Lead Actor

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And to add, it further pays for the individual to bear in mind these numbers as a mismatch in the wrong direction can prevent you reaching the full potential of your amp and conversely you can make your amp scream with agony as it in turn makes your speakers scream in agony with settings that overdrive the amp. And they say there's a lack of standardization with computer peripherals!

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