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Posted By: Ray E. Strode PRE-AMPLIFIERS - 11/10/19 05:04 PM
Today or in past applications there are about 3 different applications of Pre-Amplifiers

1. In Conjunction with a Condenser Microphone.
2. With or in a Amplifier or Receiver for a Magnetic Phono Cartridge.
3 A Tape head deck with no electronics.

In each case the voltage isn't strong enough on it's own to power a main amplifier without mass distortion.

Ampex made some tape decks with no electronics so you would have to get a pre-amp to play the tapes.
If you buy a Receiver or Amplifier with a Phono input the electronics are built in and no extra pre-amp is needed.
Sometimes with a condenser microphone the pre-amp is included with the Mic.

The RIAA Curve. When cutting a master disc to make a vinyl record there is a comensating circut that reduces the base frequencies so the cutting lathe doesn't cut back in the grove that has just been cut. This probably needs some adjustment of the levels.
This compension is added back in the electronics in a phono pre-amp so it all sounds ok. This curve is still used today.

A main amplifier circut needs about 1 volt peak to peak to drive it to normal levels. All other inputs on a receiver or amplifier is is set to use the 1 volt input without extra amplification.

I have seen where some people want a pre-amp that colors the sound. No such pre-amp is made. The only place where adjustments are made is with the tone controls on a receiver or amplifier.
Posted By: R&M Re: PRE-AMPLIFIERS - 12/31/20 02:15 AM
I had a cassette karaoke that I used to start. Along with an all in one stereo with a delay pedal.
Did not have much to mix on outside of a reverb unit.
Had a stereo delay pedal for compression.
I would like to learn analog the proper way.
Digital technology reveals all the sins.
Everything is a lot fatter with it.
A whole new way of learning and perception.
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