Home Amp/Preamp Asylum

Looking for a new Amp or Preamp? If you're after tubes, post over here.

RE: 'Loading' a preamp with a poweramp, input impedance, and the load resistor

"I achieved your goal and my goal of decreasing the Voltage gains of several poweramps by adding a resistor in series. That does indeed increase the resistance, decrease the preamp's load, and decrease the Voltage gain of the poweramp."

This is completely incorrect or stated in such a way as to make no sense.

The power amp's gain is fixed by the internal circuit topology. Nothing you do to the signal BEFORE the input to the amp will change the gain of the amp IN ANY WAY. It is already fixed. If you reduce the amplitude of the signal BEFORE the input of the amp you will get less signal out of the amp because the gain of the amp is constant. A smaller signal in will result in a smaller signal out.

This, of course, has nothing to do with the input impedance, this is simply attenuating a signal using a resistor in SERIES forming a voltage divider with the load resistor. This, naturally, adds noise to the signal and degrades the sound; so is not recommended unless you can find a "perfect" resistor.


This post is made possible by the generous support of people like you and our sponsors:
  Kimber Kable  


Follow Ups Full Thread
Follow Ups

FAQ

Post a Message!

Forgot Password?
Moniker (Username):
Password (Optional):
  Remember my Moniker & Password  (What's this?)    Eat Me
E-Mail (Optional):
Subject:
Message:   (Posts are subject to Content Rules)
Optional Link URL:
Optional Link Title:
Optional Image URL:
Upload Image:
E-mail Replies:  Automagically notify you when someone responds.