Brizm
Ear training
Theory only becomes useful when you can hear it. Five minutes a day here will do more for your productions than an hour of reading. Start on the easiest level and move up when you're scoring above 80%.
Sing or hum the two notes before answering, and link each interval to its feeling from the intervals lesson. For chords, listen first for major versus minor (bright or dark), then for the 7th (smooth or tense), then for the 9th (extra shimmer on top).
Why it pays off in the studio
Naming what you hear is how you copy a bassline from a record, pick the chord under a vocal or notice that a stab is a minor 9th rather than a plain minor chord. The quizzes play the same keys sound as the chord builder in the chords lesson, so you can check any answer there by building the chord yourself.