The sound engineering jargon "mixing with eyes" means using visual displays from frequency spectrum analyzers and loudness meters such as VU (volume unit), dBFS, LUFS, K-Weighted meters, Sonograms, etc. to make audio mixing decisions. The same meaning applies to "mastering with your eyes" except this would be in the context of audio post-production.
Although this technique can be useful in some cases, however, at the end of the day people listen to music without frequency analyzers and loudness meters in front of them. It eventually comes down to how everything sounds in a pair of ears.
Thusly, it's always advised to "mix with your ears" first before reaching for any frequency analyzer to figure out what's going on, and not to stress too much about certain sounds being at a specific dBFS level e.g. - 6 dBFS, -9 dBFS, etc. Long story short: if it sounds good, it sounds good, that's all.
Although this technique can be useful in some cases, however, at the end of the day people listen to music without frequency analyzers and loudness meters in front of them. It eventually comes down to how everything sounds in a pair of ears.
Thusly, it's always advised to "mix with your ears" first before reaching for any frequency analyzer to figure out what's going on, and not to stress too much about certain sounds being at a specific dBFS level e.g. - 6 dBFS, -9 dBFS, etc. Long story short: if it sounds good, it sounds good, that's all.
