Hi ! after i discovered LTspice and kindly got very good settings i started playing with very basic circuits
I have a CFP circuit It can be wired either as low gain line preamp or as unity gain buffer just taking out the feedback resistor
My impression after trying different resistors and voltage supply values that gain usually introduces about 10 to 20dB of 2nd order HD ...
I mean for the same 2V output the 1kHz distortion spectrum of the buffer looks much cleaner
Does this mean that generally adding gain tends to increase THD ? even if the gain is just 2 o 3 times ?
I have a CFP circuit It can be wired either as low gain line preamp or as unity gain buffer just taking out the feedback resistor
My impression after trying different resistors and voltage supply values that gain usually introduces about 10 to 20dB of 2nd order HD ...
I mean for the same 2V output the 1kHz distortion spectrum of the buffer looks much cleaner
Does this mean that generally adding gain tends to increase THD ? even if the gain is just 2 o 3 times ?
Good morning and thank you for your kind and very useful reply/advice
Clearly mine is a question from a rather ignorant person
I knew of a relationship between gain and bandwidth of a device with bandwidth decreasing as gain increases
But I knew nothing about a relationship between gain and distortion and now I know it exists
If I understand correctly the distortion comes from the lack of linearity of the transistors and that the effort that is made is in designing and building circuits that cure this lack of linearity ?
And CFP is one of the most famous I think
Also browsing the site I'm trying to understand if there are other methods
One thing I have understood very well
A low THD+noise value is the basis of a beautiful sound
And this explains all the efforts that designers make to minimize THD and noise
I think i will start from a CFP buffer and try to understand how its THD varies wihe bias and supply voltage
I am attaching the .asc file
Clearly mine is a question from a rather ignorant person
I knew of a relationship between gain and bandwidth of a device with bandwidth decreasing as gain increases
But I knew nothing about a relationship between gain and distortion and now I know it exists
If I understand correctly the distortion comes from the lack of linearity of the transistors and that the effort that is made is in designing and building circuits that cure this lack of linearity ?
And CFP is one of the most famous I think
Also browsing the site I'm trying to understand if there are other methods
One thing I have understood very well
A low THD+noise value is the basis of a beautiful sound
And this explains all the efforts that designers make to minimize THD and noise
I think i will start from a CFP buffer and try to understand how its THD varies wihe bias and supply voltage
I am attaching the .asc file