This is well-known and one reason some audiofools are rightfully laughed at for not doing when comparing speakers or cables or whatever they want to wax lyrical

This is well-known and one reason some audiofools are rightfully laughed at for not doing when comparing speakers or cables or whatever they want to wax lyrical with flowery descriptions about. All AB testing of audio equipment should be done with volume matched. Even 0.1dB difference can skew results I believe. Also the switching should be as quick as possible because auditory memory is short. More bass also corresponds to better reported listening tests. Harman did a lot of great blind testing on this and came up with preferred frequency response curves and speaker characteristics (smooth directivity rolloff and a target in-room response).