Overview of all final sample stars' signal-to-noise ratio (S/N) from serval, temperature from Gaia DR2, and evolutionary phase according to MIST photometry (color coded; the legend shows the number of stars per phase). Top left: Distribution of S/N over temperature within the sample. The circle size corresponds to the number of observations for that star. The dashed, horizontal lines mark S/N values of 100, 200, and 300. Top right: S/N for the coadded spectra in the sample. Bottom left: Distribution of temperatures within the sample.