music is not loud enough

using Audacity 2.3.2 on Windows 10

I recorded some music from the internet. But the original recording was too quiet and the result is also too quiet. How do I go about making it louder?

The Youtube speaker setting is at %100
The Audacity playback volume is at %100.
The Windows speaker setting was already at %100.
The Windows volume mixer shows speaker at %100. (probably some of these are redundant)

The first thing would be to use the Amplify or Normalize effects to “maximize” the volume. (The default settings are OK for either effect.)

If they are not loud enough after that it gets “complicated” because you are limited by the peaks, but the peaks don’t correlate well with perceived loudness. i.e. If you normalize/maximize all of your files they won’t sound equally loud.

You can use compression and/or limiting with make-up gain to bring-up the volume more but this reduces the dynamic contrast in the music.

Many of the online streaming sites are using volume matching. They are not using compression & limiting and many/most songs, including quiet-sounding songs, are already normalized so they can’t be boosted without clipping. That means the only way to volume-match is to turn-down the louder tracks, and most songs end-up being reduced in volume. (ReplayGain and other similar volume-matching tools do the same thing.)