# Alternate lab — any shape, strict DUDU

> Interactive page: [`alternate-lab.html`](alternate-lab.html) · Lessons: [`alternate.html`](alternate.html)

Build a **drill cell** or **scale shape** run with alternate (or economy) picking. Defaults: **alternate** + **minor pentatonic** + **6 strings**.

**Scales intention:** load real systems under DUDU — see [Alternate · scales job](alternate.md#scales-job) and [Scales](scales.md).

**4/4:** Up-then-down **repeats the peak** so note counts stay even (bars of 4/4 on eighths). Stats show bar count.

**String expansion:** presets **2 / 4 / 6** (2–4 start on D; 6 starts on low E). Drill modes: **NPS cell** (2 / 3 / 4NPS spider) or **Crawl** (outside/inside across the chosen strings).

**Controls:** picking toggle · Drill cell / Scale shape · string presets · direction · start stroke · subdivision · prefer fret · from string · num strings · (drill) NPS or crawl side · (scale) root · system · shape.

TAB updates live (`#pl-tab`). **Play loop** follows the sounding note. X row: `o` / `i` / `=`.

**Path:** [Alternate lessons](alternate.md) → this lab → [Economy lab](economy-lab.md) → [Solo drills · alternate](drills-solo.md#alt)