michael_d,
The controlling device is your (stereo or multichannel) preamp--either a separate one or the preamp section inside your AV receiver.
The level control in the preamp meters out the low varying voltage to its pre-outs, depending on the level setting, then to the amplifier inputs. Where you set the "volume" control adjusts the preamp circuitry to send a signal that will vary (with the dynamics of the music signal) from a few millivolts to perhaps 1 volt or more. As JohnK mentioned, most amplifiers have 28 to 30 dB of gain, which means that if the amp section in your outboard power amp or inside your AV receiver is getting a 1-volt input signal, it will be close to delivering its full output to the speakers.
Alan
Alan,
Thanks, but I’m still confused. When I referred earlier to the sine wave input signal I was referring to what you are, the pre-amp output to the “amp”. The “amp”, whether it is an actual physical device or component in the receiver (amplifier or transistor) or if it is working sum of all components is where my confusion lies.
John has stated that a receiver has one power supply and one amplifier. He also states (and so does Chris), that these “transistors” act as gates for current flow to each channel and that share a common “pool” of power which is supplied by the power supply.
I need a block diagram. Anyone know where one might reside on the web?
