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## Chapter 18 – Sound and Music

Unlike its predecessors, your ZX Spectrum Next doesn't fare poorly in the audio capabilities department. From simple beeps and clicks, to complex compositions using its in-built 3 Programmable Sound Generators (*PSGs*) and full-fledged digital audio output, sound can accompany almost every program you write or software you will load. Sound is output in stereo from both the *digital video port* and an analogue 3.5mm jack output present on the back of the machine. Additionally, there is the possibility of an on-board *piezo speaker* (sold separately).

### Basic sounds with the BEEP command

The easiest way to create sounds (and the only method that works on all ZX BASIC versions including *NextBASIC*) is by using the **BEEP** statement:

**BEEP** *duration, pitch*

where, as usual, *duration* and *pitch* represent any numerical expressions. The *duration* is given in *seconds*, and the *pitch* is given in *semitones* above *middle C*. For notes below *middle C* we use negative numbers.

Here is a diagram to show the pitch values of all the notes in one *octave* on the piano:

![Fig. 17 – Pitch/note equivalents](/documentation/manual/rev3/figures/p144-fig17-pitch-note-equivalents.png)
```
   -2    1    3         6    8   10        13   15
   B♭   D♭   E♭        G♭   A♭   B♭        D♭   E♭
   A♯   C♯   D♯        F♯   G♯   A♯        C♯   D♯

 -3   -1    0    2    4    5    7    9   11   12   14   16
  A    B    C    D    E    F    G    A    B    C    D    E
```

*Fig. 17 – Pitch/note equivalents*

To get higher or lower notes, you have to add or subtract **12** for each *octave* that you go up or down.

If you have a piano in front of you when you are programming a tune, this diagram will probably be all that you need to work out the pitch values. If, however, you are transcribing straight from some written music, then we suggest that you draw a diagram of the stave with the pitch value written against each line and space, taking the key into account.

For example, type:

```
10 PRINT "Frere Gustav"
20 BEEP 1,0: BEEP 1,2: BEEP .5,3: BEEP
   .5,2: BEEP 1,0
30 BEEP 1,0: BEEP 1,2: BEEP .5,3: BEEP
   .5,2: BEEP 1,0
40 BEEP 1,3: BEEP 1,5: BEEP 2,7
50 BEEP 1,3: BEEP 1,5: BEEP 2,7
60 BEEP .75,7: BEEP .25,8: BEEP .5,7:
   BEEP .5,5: BEEP .5,3: BEEP .5,2: BEEP
   1,0
70 BEEP .75,7: BEEP .25,8: BEEP .5,7:
```