4-Note Sequences + Landing on Chord 3rds: C for Am7, F# for D7

Here's why we're doing this today. So far, we've only been playing over a single Am7 chord. But the moment Dorian really shines is when the chord moves Am7 → D7 → Am7. Today we're introducing that progression, and along with it, I'm going to show you something that'll give you chills.

First, the 4-note sequence. Yesterday we swept through 3rds, so today it's 4-note groups. You take the scale in groups of four and shift up one step at a time.

• A-B-C-D / B-C-D-E / C-D-E-F# / D-E-F#-G …

If 3rds are a "swinging leap," 4-note groups are a "rolling wave." Your fingers roll tightly through the whole scale, and starting from the third and fourth groups, F# (the major 6th) naturally rises up onto the surface of that wave. Today's warm-up rolls your hand through exactly this.

Now, the real heart of today. When the backing shifts from Am7 → D7, let's look at the 3rd of each chord:

• Am7's 3rd = C (out of A-C-E-G, C is the b3, the minor 3rd)
• D7's 3rd = F# (out of D-F#-A-C, it's F#)

See it? D7's 3rd is exactly F#. And F# is the very note we've been treasuring all week — A Dorian's major 6th (the color note). In other words, the moment the chord changes to D7, if you simply land on F# — that's targeting D7's 3rd, and at the same time it's the moment Dorian's color explodes. Two birds meet in one note. That's the secret behind why Dorian sounds so "sophisticated" over a minor progression.

So here's today's grammar in a nutshell: land on C (the b3) during the Am7 section, land on F# (the 6th = D7's 3rd) during the D7 section. The chord changes, so the landing note changes — that same sense you learned with guide tones last week, now combined with modal color.

First, here's the A Dorian 4-note sequence (2 bars, eighth notes). It rolls up starting from the 6th string. In the third and fourth groups, F# (the 6th, the color note) rises up onto the wave (highlighted).

Second, here's the Am7 vs. D7 target-3rds map. Two kinds of highlights: C (Am7's 3rd) in green and F# (D7's 3rd = the Dorian color) in yellow. See with your own eyes how F# plays double duty. The roots A and D are marked too, for reference.

Third, here's a 4-bar line that burns "chord change = landing change" into your body. The two Am7 bars land on C (the b3), the two D7 bars land on F# (the 6th). Sing each landing note with vibrato.

0–10 min · Warm-up (BPM 80) — 4-note sequence With the metronome at 80, roll through the first 4-note sequence. Keep that tight, rolling feel in your fingers, and add just a touch of clarity when F# (string 5 fret 9) rises up onto the wave. Doing it both up and back (climb, then come back down the same pattern) really loosens your hand up.

10–20 min · Brain training (mapping landing 3rds) Looking at the second map, alternate between fretting Am7's C (three spots) and D7's F# (two spots). Say it out loud as you go: "Am7 means C, D7 means F#." Finally, close your eyes: "D7 now! → the nearest F#" — if you can find it within 3 seconds, you pass. The goal is making "chord name → landing note" into a reflex.

20–40 min · Real-world improv (Am7-D7 vamp / 76–80 BPM) Put on an "Am7 D7 vamp backing track" (alternating every two bars). One mission: land on that chord's 3rd every time the chord changes. C at the end of the Am7 section, F# at the end of the D7 section. Feel free to start by dropping the third 4-bar line straight on top. Fill the space in between freely — just make sure the landing note always matches the chord.

40–50 min · Record & reflect (recommended) Record the last 30 seconds of your jam. Listen back and check two things: ① did you land on F# the moment it switched to D7? ② did the sound "sparkle" brighter right then? Slow playback to 0.75x to check whether the chord change and your landing line up.

Today's finish line: Run the 4-note sequence up and back at 80. Point to "chord name → landing note (C/F#)" within 3 seconds. Successfully land on the right 3rd at least 6 times per chord over the Am7-D7 backing track.

• Not changing the landing note when the chord changes. This is the most common mistake. If you keep landing on C no matter whether it's Am7 or D7, the D7 section falls flat. Remember: D7 = F#. This switch is everything today.
• Feeling "scared" of F#. Over Am7, F# is a color note (the major 6th); over D7, it's an actual chord tone (the 3rd). That means during the D7 section, F# is the safest note there is. Don't be afraid — lean right into F# when D7 arrives.
• Playing the 4-note groups too fast. 4-note groups are tightly packed, so even 80 can tangle your fingers. If you tangle, drop to 70 and roll through without smudging a single note — accuracy first. A smudged 4-note run is useless.
• Focusing only on landings, letting the in-between get choppy. The landing note is the destination, but the road there (the in-between notes) needs to be smooth too. In the note or two right before a landing, step in stepwise (right next to the landing note) so you glide in naturally.