Audio AMP Power vs THD+N ratio

[glatocha]

Hi,

I am designing audio class D amp with TI TPA3125 2x10W amp.
I have found the screen as attached showing THD+N vs supply voltage and output power.
I would prefer to have lower THD+N and this 1 or 1.5W less power is ok for me. But how can I choose at which THD+N it will work?

What determines which curve is actually working.

I have the feeling that I misunderstand the whole concept of this. Can somebody help me out?
Regards

[David_AVD]

Do you have a specific operating voltage in mind?  If so, find that on the bottom of the graph.  Follow it up to where it intersects the blue line (1% THD).  Then see what max power output that corresponds to on the vertical axis of the chart.

Basically, they are telling you the maximum power output vs voltage with 1% and 10% options.

[w2aew]

THD+N is a function of supply voltage and output power. For example, for a supply of 20V, the THD+N will be 1% or less if the output power is kept below 6W. If the signal is turned up to the point where the power exceeds 7W, then the THD+N will approach 10%.   The curves are intended to show you how these three parameters are related.

[glatocha]

So, basically if the Amplifier has a constant gain it will depend on my input amplitude?

I think I am beginning to understand

[David_AVD]

yes

[glatocha]

Thank you all