8.2 Chords

# Ackord

Sonic Pi has built-in support for chord names which will return lists. Try it for yourself:

```
play chord(:E3, :minor)
```

Now, we're really getting somewhere. That looks a lot more pretty than the raw lists (and is easier to read for other people). So what other chords does Sonic Pi support? Well, a *lot*. Try some of these:

* `chord(:E3, :m7)`
* `chord(:E3, :minor)`
* `chord(:E3, :dim7)`
* `chord(:E3, :dom7)`

## Arpeggios

We can easily turn chords into arpeggios with the function `play_pattern`:

```
play_pattern chord(:E3, :m7)
```

Ok, that's not so fun - it played it really slowly. `play_pattern` will play each note in the list with a call to `sleep 1` after each call to `play`. We can use another function `play_pattern_timed` to specify our own timings and speed things up:

```
play_pattern_timed chord(:E3, :m7), 0.25
```

We can even pass a list of times which it will treat as a circle of times:

```
play_pattern_timed chord(:E3, :m13), [0.25, 0.5]
```

This is the equivalent to:

```
play 52, sustain: 0.25
sleep 0.25
play 55, sustain: 0.5
sleep 0.5
play 59, sustain: 0.25
sleep 0.25
play 62, sustain: 0.5
sleep 0.5
play 66, sustain: 0.25
sleep 0.25
play 69, sustain: 0.5
sleep 0.5
play 73, sustain: 0.25
sleep 0.25
```

Which would you prefer to write?

Note that `play_pattern` and `play_pattern_timed` alter the sustain of the notes to fill the times. You can remove this behavior by setting the `sustain:` opt to `0`:

```
play_pattern_timed chord(:E3, :m13), [0.25, 0.5], sustain: 0
```
