# Total Harmonic Distortion

If a specific project specification says "...amplifier must be linear such that the harmonic distortions are maintained below -40dB...", does that mean that a THD of -30dB would meet the requirements or would something like -50dB be correct?

I ask this because I know with gain, $A_v$, we usually take absolute values so it's a little hard to understand which one is correct. Any ideas?

For power, -40dB is a ratio of $\frac{1}{10,000}$ while -50dB is a ratio of $\frac{1}{100,000}$.