Chapter 13: Making Some Noise — Crash BASIC - Make Cross Platform 2D Games in BASIC

Example Assets Needed:
To follow along with this chapter's examples, you'll need these sound files:

Sound Effects (.wav): jump.wav, land.wav, hurt.wav, coin.wav, pickup.wav, laser.wav, explosion.wav, shoot.wav

Music (.mp3): background_music.mp3 or game_music.mp3

You can find free sound effects at OpenGameArt.org, Freesound.org, or use tools like BFXR/SFXR to generate retro game sounds. For music, check out Incompetech or the Free Music Archive.

What's the difference between a game and an experience?

Sound.

Think about it. Picture Mario without the jump sound. Sonic without the ring ding. Zelda without that triumphant chest-opening fanfare. Half the magic would be GONE.

Sound isn't just decoration—it's feedback. It tells players "yes, you did that!" It builds tension. It creates atmosphere. It makes your game feel ALIVE.

And guess what? Adding sound to Crash BASIC is super easy. Let's get LOUD!

The Simplest Sound: BEEP

Let's start with the most basic sound possible:

SCREEN 13

PRINT "Press any key to BEEP!"
PAUSE
BEEP

PRINT "You beeped!"
PAUSE

BEEP does exactly what you think—it makes a beep. It's not exciting, but it's SOMETHING. Great for quick feedback when you don't have custom sounds yet.

SOUND: Old-School Synthesized Tones

Want more control? SOUND lets you specify a frequency and duration:

SCREEN 13

' SOUND frequency, duration (in milliseconds)
SOUND 440, 500     ' A4 note for half a second
SOUND 880, 500     ' A5 note (one octave higher)
SOUND 220, 1000    ' A3 note (one octave lower) for 1 second

PAUSE

This creates pure synthesized tones—like an old computer! Here are some musical frequencies to play with:

Note	Frequency
C4 (Middle C)	262
D4	294
E4	330
F4	349
G4	392
A4	440
B4	494
C5	523

A Simple Melody

SCREEN 13

PRINT "Playing a scale..."

' C major scale
SOUND 262, 300    ' C
SOUND 294, 300    ' D
SOUND 330, 300    ' E
SOUND 349, 300    ' F
SOUND 392, 300    ' G
SOUND 440, 300    ' A
SOUND 494, 300    ' B
SOUND 523, 600    ' C (hold longer)

PRINT "Done!"
PAUSE

Real Sound Effects: WAV Files

Okay, synthesized beeps are fun for retro games, but you probably want REAL sounds—explosions, laser blasts, footsteps, the works!

That's where WAV files come in. WAV is a standard sound format that works great for short sound effects.

Loading and Playing WAV Files

SCREEN 13

' First, load the sound (do this at the start of your program)
LOADWAV "laser.wav", "laser"
LOADWAV "explosion.wav", "boom"
LOADWAV "coin.wav", "ding"

PRINT "Press L for laser, E for explosion, C for coin!"
PRINT "Press Q to quit."

DO
    k$ = INKEY$

    IF k$ = "l" OR k$ = "L" THEN
        PLAYWAV "laser"
    END IF

    IF k$ = "e" OR k$ = "E" THEN
        PLAYWAV "boom"
    END IF

    IF k$ = "c" OR k$ = "C" THEN
        PLAYWAV "ding"
    END IF

    DELAY 16
LOOP UNTIL k$ = "q" OR k$ = "Q"

The pattern is simple:

LOADWAV "filename.wav", "nickname" — Load the file and give it a short name
PLAYWAV "nickname" — Play it whenever you want!

Why Load First?

Loading sounds takes time—the computer has to read the file from disk. If you loaded sounds in your game loop, there'd be a tiny pause every time you played one. Yuck!

By loading everything at the START of your program, all your sounds are ready to go instantly. No lag, no stutter.

' ===== LOADING PHASE (do this ONCE at startup) =====
LOADWAV "jump.wav", "jump"
LOADWAV "land.wav", "land"
LOADWAV "hurt.wav", "ouch"
LOADWAV "pickup.wav", "item"

' ===== GAME LOOP (sounds play instantly!) =====
DO
    ' ... game logic ...

    IF playerJumped THEN
        PLAYWAV "jump"
    END IF

    ' ... more game logic ...
LOOP

Background Music: MP3 Files

WAV files are great for sound effects, but they're BIG. A 3-minute song as a WAV file could be 30+ megabytes!

For music, use MP3 files. They're compressed, so a whole song might only be 3-5 megabytes.

SCREEN 13

' Load the music
LOADMP3 "background_music.mp3", "bgm"

' Start playing (the 1 means LOOP forever)
PLAYMP3 "bgm", 1

PRINT "Music is playing!"
PRINT "Press S to stop, P to play again, Q to quit."

DO
    k$ = INKEY$

    IF k$ = "s" OR k$ = "S" THEN
        STOPMP3 "bgm"
        PRINT "Music stopped."
    END IF

    IF k$ = "p" OR k$ = "P" THEN
        PLAYMP3 "bgm", 1
        PRINT "Music playing!"
    END IF

    DELAY 16
LOOP UNTIL k$ = "q" OR k$ = "Q"

STOPMP3 "bgm"

The Loop Parameter

PLAYMP3 "bgm", 0    ' Play once, then stop
PLAYMP3 "bgm", 1    ' Loop forever (for background music)

For background music, you almost always want 1 (loop). For a victory fanfare or game over jingle, use 0 (play once).

MML: Music Macro Language

Here's something really cool—you can write music directly in your code using MML (Music Macro Language)! It's like a mini programming language just for music.

SCREEN 13

' Play a simple tune
PLAY "C D E F G A B >C"

PAUSE

The > means "go up one octave." The < means "go down one octave."

MML Commands

Command	Meaning	Example
C D E F G A B	Notes	`PLAY "C D E"`
R	Rest (silence)	`PLAY "C R E"`
>	Octave up	`PLAY "C >C"`
<	Octave down	`PLAY ">C <C"`
O	Set octave (1-8)	`PLAY "O4 C"`
L	Note length (1=whole, 4=quarter, 8=eighth)	`PLAY "L8 C D E"`
T	Tempo (beats per minute)	`PLAY "T120 C D E"`
+ or #	Sharp	`PLAY "C+ D"`
-	Flat	`PLAY "B- C"`
I	Instrument (0-66)	`PLAY "I5 C D E"`
V	Volume (0-15)	`PLAY "V10 C D E"`

Synthesized Instruments

Here's where MML gets REALLY fun. The I command lets you choose from 67 different synthesized instruments! These are all generated in real-time—no sound files needed.

Basic Waveforms (I0-I9):

#	Instrument	Sound
I0	Sine beep	Pure, clean tone
I1	Square chiptune	Classic retro game sound
I2	Square + vibrato	Warbling chiptune
I3	Pulse narrow	Thin, bright
I4	Pulse wide	Fuller pulse
I5	Sawtooth	Buzzy, bright
I6	Sawtooth + vibrato	Expressive sawtooth
I7	Triangle	Mellow, flute-like
I8	Triangle + vibrato	Expressive triangle
I9	Square + tremolo	Volume modulation

Lead Instruments (I10-I19):

#	Instrument	Sound
I10	Sawtooth bass	Deep, rich low-end
I11	Square lead	Bright lead
I12	Sine pitch sweep	Swooping attack
I13	Sawtooth lead	Sharp melodic lead
I14	Triangle chorus	Spacious triangle
I15	Noise channel	Percussion/effects
I16	Bell	Sine with harmonics
I17	Organ	Multiple harmonic layers
I18	Pluck	Fast decay (string-like)
I19	Pad	Slow attack (atmospheric)

Advanced Synthesis (I20-I29):

#	Instrument	Sound
I20	FM synthesis	Complex frequency modulation
I21	Distorted square	Overdriven chiptune
I22	Brass-like	Rich harmonic content
I23	String-like	Bowed string simulation
I24	Flute-like	Airy woodwind
I25	Choir-like	Multiple voice layers
I26	Synth bass	Electronic bass
I27	Acid bass	Filtered sawtooth
I28	PWM	Pulse width modulation
I29	Vocoder-like	Formant synthesis

Percussion & Drums (I30-I39):

#	Instrument	Sound
I30	Kick drum	Deep bass drum
I31	Snare drum	Snappy with noise
I32	Hi-hat	Crisp high-frequency
I33	Crash cymbal	Sustained crash
I34	Tom drum	Pitched tom
I35	Rim shot	Sharp rim click
I36	Clap	Hand clap
I37	Wood block	Percussive wood
I38	Cowbell	Metallic bell tone
I39	Shaker	High-frequency rhythm

Special Effects (I40-I50):

#	Instrument	Sound
I40	Laser zap	Sci-fi laser
I41	Explosion	Dramatic explosion
I42	Power-up	Ascending game sound
I43	Coin pickup	Classic arcade coin
I44	Jump sound	Character jump
I45	Damage sound	Hit/damage effect
I46	Door creak	Slow creaking
I47	Wind sound	Atmospheric wind
I48	Water drop	Liquid drop
I49	Bubble pop	Small bubble burst
I50	Alien voice	Otherworldly vocal

Futuristic NES Patches (I51-I58):

#	Instrument	Sound
I51	Futuristic Lead	Authentic NES 12.5% duty
I52	Futuristic Arpeggio	Fast triad cycling
I53	Futuristic Bass	Triangle wave, punchy
I54	Futuristic Kick	Triangle pitch drop
I55	Futuristic Pulse Bass	NES 25% duty
I56	Futuristic Snare	Noise burst with pitch
I57	Futuristic Echo Lead	50% duty with delay
I58	Futuristic Tom	Tuned triangle drum

Gothic NES Patches (I59-I66):

#	Instrument	Sound
I59	Gothic Lead	Dramatic square vibrato
I60	Gothic Strings	Sawtooth with vibrato
I61	Gothic Bass	Deep, dark triangle
I62	Gothic Organ	Church organ harmonics
I63	Gothic Melody	NES 25% + gentle vibrato
I64	Gothic Bell	Clock tower atmosphere
I65	Gothic Pad	Atmospheric background
I66	Gothic Accent	Sharp dramatic attack

Using Instruments

SCREEN 13

' Play a chiptune melody
PLAY "I1 T140 L8 O4 C E G >C <G E C"

' Drum beat
PLAY "I30 L4 C P4 I31 C P4 I30 C I32 L8 C C"

' Sound effect
PLAY "I43 L16 C E G >C"    ' Coin pickup!

PAUSE

A Real Melody

SCREEN 13

' "Mary Had a Little Lamb" in MML
PLAY "T120 L4 E D C D E E E R D D D R E G G R"
PLAY "E D C D E E E E D D E D C"

PAUSE

Background MML Music

By default, PLAY waits until the music finishes. But what if you want the music to play while your game runs? Use the BACKGROUND keyword:

SCREEN 13

' Start music in the background
PLAY BACKGROUND "T120 L8 O4 C D E F G A B >C <B A G F E D C"

' Game can run while music plays!
FOR i = 1 TO 100
    PRINT "Game running... "; i
    DELAY 50
NEXT i

' Stop the background music when done
STOP PLAY

PAUSE

Stopping Sounds

Sometimes you need to stop a sound—maybe the player paused the game, or the background music needs to change.

' Stop specific sounds
STOPWAV "laser"       ' Stop a WAV sound
STOPMP3 "bgm"         ' Stop MP3 music
STOP PLAY             ' Stop MML music

' Sounds can be played again after stopping
PLAYMP3 "bgm", 1      ' Resume music

Real Example: A Game with Sound

Let's put it all together! Here's a simple dodge game with full audio:

SCREEN 13

' =============================================
' LOADING PHASE - Load all sounds up front!
' =============================================
LOADWAV "jump.wav", "jump"
LOADWAV "coin.wav", "coin"
LOADWAV "hurt.wav", "ouch"
LOADMP3 "game_music.mp3", "music"

' Start background music
PLAYMP3 "music", 1

' =============================================
' GAME SETUP
' =============================================
playerX = 160
playerY = 180
playerVY = 0
onGround = TRUE
score = 0
lives = 3

coinX = INT(RND * 280) + 20
coinY = INT(RND * 100) + 50

enemyX = 320
enemyY = 180
enemySpeed = 3

' =============================================
' GAME LOOP
' =============================================
DO
    ' --- INPUT ---
    IF KEYDOWN("LEFT") AND playerX > 10 THEN
        playerX = playerX - 4
    END IF

    IF KEYDOWN("RIGHT") AND playerX < 310 THEN
        playerX = playerX + 4
    END IF

    IF KEYDOWN("SPACE") AND onGround THEN
        playerVY = -12
        onGround = FALSE
        PLAYWAV "jump"    ' JUMP SOUND!
    END IF

    ' --- PHYSICS ---
    playerVY = playerVY + 1    ' Gravity
    playerY = playerY + playerVY

    IF playerY >= 180 THEN
        playerY = 180
        playerVY = 0
        onGround = TRUE
    END IF

    ' --- ENEMY MOVEMENT ---
    enemyX = enemyX - enemySpeed
    IF enemyX < -20 THEN
        enemyX = 340
        enemySpeed = enemySpeed + 0.2    ' Get faster!
    END IF

    ' --- COLLISION: Coin ---
    IF ABS(playerX - coinX) < 15 AND ABS(playerY - coinY) < 15 THEN
        PLAYWAV "coin"    ' COIN SOUND!
        score = score + 10
        coinX = INT(RND * 280) + 20
        coinY = INT(RND * 100) + 50
    END IF

    ' --- COLLISION: Enemy ---
    IF ABS(playerX - enemyX) < 15 AND ABS(playerY - enemyY) < 15 THEN
        PLAYWAV "ouch"    ' HURT SOUND!
        lives = lives - 1
        enemyX = 340      ' Reset enemy

        IF lives <= 0 THEN
            STOPMP3 "music"    ' Stop music on game over
            CLS
            PRINT "GAME OVER!"
            PRINT "Final Score: "; score
            PAUSE
            END
        END IF
    END IF

    ' --- RENDER ---
    BEGIN FRAME
    CLS

    ' Ground
    LINE (0, 190)-(319, 199), 2, BF

    ' Player (yellow circle)
    CIRCLE (playerX, playerY), 10, 14, 14

    ' Coin (gold circle)
    CIRCLE (coinX, coinY), 8, 14

    ' Enemy (red square)
    LINE (enemyX - 10, enemyY - 10)-(enemyX + 10, enemyY + 10), 4, BF

    ' UI
    LOCATE 1, 1
    PRINT "Score: "; score; "  Lives: "; lives

    END FRAME
    DELAY 16
LOOP

Notice how sound makes the game feel so much more responsive:

Jump sound confirms the player's action
Coin sound provides satisfying feedback for collecting
Hurt sound makes damage feel impactful
Background music keeps the energy up

Sound Best Practices

1. Load Everything at the Start

' GOOD: Load once, play many times
LOADWAV "shoot.wav", "shoot"

DO
    IF shooting THEN PLAYWAV "shoot"
LOOP

' BAD: Loading in the game loop causes stuttering!
DO
    IF shooting THEN
        LOADWAV "shoot.wav", "shoot"    ' DON'T DO THIS!
        PLAYWAV "shoot"
    END IF
LOOP

2. Use WAV for Effects, MP3 for Music

WAV: Sound effects (short, need instant playback)
MP3: Music (long, can afford slight delay, much smaller files)

3. Keep Sound Effects Short

Sound effects should be 1-3 seconds max. Long sounds can overlap weirdly and eat up memory.

4. Don't Overlap the Same Sound Too Much

If the player fires 10 lasers per second, you might get weird audio artifacts. Consider limiting how often a sound can play:

lastLaserTime = 0

IF shooting AND TIMER - lastLaserTime > 100 THEN
    PLAYWAV "laser"
    lastLaserTime = TIMER
END IF

5. Stop Music When Appropriate

Don't let background music play during menus or cutscenes if it doesn't fit:

' Pause menu
STOPMP3 "game_music"
' ... show pause screen ...
PLAYMP3 "game_music", 1    ' Resume when unpaused

Quick Reference

Command	What It Does
`BEEP`	Play a simple beep
`SOUND freq, duration`	Play a tone (frequency in Hz, duration in ms)
`LOADWAV "file", "name"`	Load a WAV file
`PLAYWAV "name"`	Play a loaded WAV
`STOPWAV "name"`	Stop a playing WAV
`LOADMP3 "file", "name"`	Load an MP3 file
`PLAYMP3 "name", loop`	Play MP3 (loop: 0=once, 1=forever)
`STOPMP3 "name"`	Stop playing MP3
`PLAY "notes"`	Play MML music
`PLAY BACKGROUND "notes"`	Play MML in background
`PLAY "I# notes"`	Play with instrument (0-66)
`PLAY "V# notes"`	Set volume (0-15)
`STOP PLAY`	Stop background MML

Try It Yourself!

Create a "Simon Says" style game where you have to repeat a sequence of tones using SOUND
Add sound effects to one of your earlier games—jump, shoot, collect, die
Write a short song using MML notation
Create a jukebox program that lets the player switch between different MP3 tracks
Make a "sound board" with buttons that play different sounds

Your games are about to sound AMAZING!

See you in Chapter 14!

Next Chapter: We'll learn about saving and loading—because losing all your progress is NO fun!

# The Simplest Sound: BEEP

# SOUND: Old-School Synthesized Tones

# A Simple Melody

# Real Sound Effects: WAV Files

# Loading and Playing WAV Files

# Why Load First?

# Background Music: MP3 Files

# The Loop Parameter

# MML: Music Macro Language

# MML Commands

# Synthesized Instruments

# Using Instruments

# A Real Melody

# Background MML Music

# Stopping Sounds

# Real Example: A Game with Sound

# Sound Best Practices

# 1. Load Everything at the Start

# 2. Use WAV for Effects, MP3 for Music

# 3. Keep Sound Effects Short

# 4. Don't Overlap the Same Sound Too Much

# 5. Stop Music When Appropriate

# Quick Reference

# Try It Yourself!