Optimizing amplifier for specific frequency bands?

[AndrewT]

Hi,
the question makes sense.
It is inherent in linear systems that 1mV input will give xmV output.
Raise the input to 2mV and out comes 2xmV and so on up the volume scale.
A wideband amp will keep this linearity across a wide frequency range as well as across the level range.

This law of linearity only breaks down when the amplifier becomes non linear eg when it clips or when the level becomes excessively contaminated by noise/distortion.
There are some circuits that deliberately become non linear with level and or frequency. FM radio gain adjustment, Dolby noise reduction and Dbx compressors are three more common examples.

 

[lumanauw]

Hi, bob_v5

The electronics may give same amplification factor, but the sound that our ear experience wouldn't be the same. Some because of loudspeaker behavior and some because of our hearing system's behavior (Fletcher Munson curve).

 

[bob_v5]

lumanauw-- this is why volume pots are usualy nonlinear right? But would it still sound right? I mean the system wouldnt (for example) give too much treble when the volume was adjusted?

 

[lumanauw]

Hi, bob_v5

I don't know, but it seems for low listening levels, a "loudness" curve (more bass and more treble) is preferable. For higher listening level, my ears prefers flat response (without loudness curve).

 

[bob_v5]

oh dear. I prefer to always keep the signal "clean", and cant think of a way around this! Any ideas anyone?

 

[Brett]

AndrewT is correct. Set your system gains up so all the amps clip at the same level, and providing they're reasonably linear, will sound much the same.