diff --git a/modulation/stereo_encoder.c b/modulation/stereo_encoder.c
index 662c6fc..6c21e63 100644
--- a/modulation/stereo_encoder.c
+++ b/modulation/stereo_encoder.c
@@ -37,7 +37,7 @@ float stereo_encode(StereoEncoder* st, uint8_t enabled, float left, float right,
 
     *audio = (mid*half_audio);
     if(st->stereo_hilbert) {
-        float stereo = (crealf(stereo_hilbert) * signalx2) + (cimagf(stereo_hilbert) * signalx2cos);
+        float stereo = (crealf(stereo_hilbert) * signalx2) - (cimagf(stereo_hilbert) * signalx2cos);
         *audio += (stereo * half_audio);
     } else *audio += ((side*signalx2) * half_audio);
     return (signalx1*st->pilot_volume);