# Selecting the Nyquist rate for a combination of signals

If several sine waves were combined but each had a separate frequency, for example 10 Hz, 20 Hz and and 30 Hz, what would the required Nyquist rate be for analysis? From my research, it suggests that Nyquist rate should be double the maximum frequency and for this case it should be 60 Hz. Is this correct or does the fact that it is a combined signal change this concept?

• I recommend this guide from @TimWescott wescottdesign.com/articles/Sampling/sampling.pdf
– Ben
Apr 14 at 18:51
• Just to follow up on Fat32's answer: The fact that multiple sines are combined does not change this concept. This presumes, however, that combined means added, in contrast to multiplied or another strange - or, more specific: nonlinear, thing. Apr 14 at 19:01
• Also following up on Fat32's answer: the formulation "Nyquist rate [...] for analysis" is a little odd. The Nyquist rate is a theoretical thing that is crucial to develop the sampling theorem, but for practical use the sample rate is essential. Apr 14 at 19:04