diff --git a/app/src/main/kotlin/net/jeena/pacer/AudioEngine.kt b/app/src/main/kotlin/net/jeena/pacer/AudioEngine.kt
index 7017918..58f7b9e 100644
--- a/app/src/main/kotlin/net/jeena/pacer/AudioEngine.kt
+++ b/app/src/main/kotlin/net/jeena/pacer/AudioEngine.kt
@@ -22,6 +22,11 @@ class AudioEngine {
     companion object {
         private const val BEEP_DURATION_MS = 40
         private const val SILENCE_CHUNK_MS = 10
+
+        // Apply a square curve so the slider feels linear to human hearing.
+        // AudioTrack.setVolume() takes a linear amplitude; our 0-1 slider
+        // value is perceived as "all the volume at the bottom" without this.
+        private fun toAmplitude(linear: Float): Float = linear * linear
     }
 
     private val mainHandler = Handler(Looper.getMainLooper())
@@ -69,7 +74,7 @@ class AudioEngine {
             .setTransferMode(AudioTrack.MODE_STREAM)
             .build()
 
-        audioTrack?.setVolume(currentVolume)
+        audioTrack?.setVolume(toAmplitude(currentVolume))
         audioTrack?.play()
 
         handlerThread = HandlerThread("PacerAudio").also { it.start() }
@@ -94,7 +99,7 @@ class AudioEngine {
 
     fun setVolume(volume: Float) {
         currentVolume = BpmCalculator.clampVolume(volume)
-        audioTrack?.setVolume(currentVolume)
+        audioTrack?.setVolume(toAmplitude(currentVolume))
     }
 
     private fun audioLoop() {