---
schema: 1
type: term
title: '**A-flat add nine**'
description: >-
  **A-flat add nine** — a piano chord (an A-flat chord with an added ninth) that
  appears in the channel's material as a hands-on example in _Codex Taught Me
  How to Play Piano_, where a MIDI keyboard connected to a Codex-built app is
  used to explore what you're playing.
canonical: >-
  https://liquidgold.cc/channel/everyinc/explore/term/a-flat-add-nine-6424c05b93f8
markdown: >-
  https://liquidgold.cc/channel/everyinc/explore/term/a-flat-add-nine-6424c05b93f8.md
llms: null
parent: 'https://liquidgold.cc/channel/everyinc/llms.txt'
channel: everyinc
updated: '2026-10-23T22:12:35.346Z'
language: null
children: []
---


# \*\*A-flat add nine\*\*

Canonical: https://liquidgold.cc/channel/everyinc/explore/term/a-flat-add-nine-6424c05b93f8

Parent: [Channel index](https://liquidgold.cc/channel/everyinc/llms.txt)

## Definition

**A-flat add nine** — a piano chord (an A-flat chord with an added ninth) that appears in the channel's material as a hands-on example in _Codex Taught Me How to Play Piano_, where a MIDI keyboard connected to a Codex-built app is used to explore what you're playing.

In this channel's material, **A-flat add nine** appears as a concrete musical example in the video *Codex Taught Me How to Play Piano*. That video shows how to connect a MIDI piano to a computer and have Codex build a small app that displays what you're playing — turning casual noodling into a way to explore and understand specific chords, songs, and techniques. A-flat add nine is one of the chords explored in that hands-on, AI-assisted piano setup. Evidence for its use is limited to this context; no other material in the captured set defines or discusses the chord in depth.