Distortion question.

[keantoken]

Hi all.

Why is it that some circuits will have really low THD that will rise rather quickly as output level increases, but others will have higher THD that will barely rise at all between output levels?

I know there is an answer to this question and I have a feeling it's OLG related.

- keantoken

[h_a]

I'm not sure there's a simple answer to that.

In general it is not obvious what the main source of distortion is and carefull investigation is necessary. I can only refer you to Douglas Self's book and webpage for more information, as he investigated the sources of distortion in detail.

In my view a rise in distortion with increasing output power is perfectly normal and also what is to be expected generally. Reason is simply that even a not perfectly linear transfer function can be linearized in a sufficiently small part; the larger the signal becomes the worse this approximation gets.

To which extend all of this applies to a particular amp also depends on negative feedback and the specific design (and a few thousand other details )

Have fun, Hannes