diff --git a/crates/dctortion/src/lib.rs b/crates/dctortion/src/lib.rs
index b895dce..681a3de 100644
--- a/crates/dctortion/src/lib.rs
+++ b/crates/dctortion/src/lib.rs
@@ -10,12 +10,18 @@ baseplug::model! {
         #[model(min = 0.0, max = 1.0)]
         #[parameter(name = "offset")]
         offset: f32,
+        #[model(min = 0.0, max = 1.0)]
+        #[parameter(name = "alternate")]
+        alternate: f32,
     }
 }
 
 impl Default for GainModel {
     fn default() -> Self {
-        Self { offset: 0.0 }
+        Self {
+            offset: 0.0,
+            alternate: 0.0,
+        }
     }
 }
 
@@ -42,8 +48,13 @@ impl Plugin for Gain {
         let output = &mut ctx.outputs[0].buffers;
 
         for i in 0..ctx.nframes {
-            output[0][i] = input[0][i] + model.offset[i];
-            output[1][i] = input[1][i] - model.offset[i];
+            if model.alternate[i] < 0.5 {
+                output[0][i] = input[0][i] + model.offset[i];
+                output[1][i] = input[1][i] - model.offset[i];
+            } else {
+                output[0][i] = input[0][i] - model.offset[i];
+                output[1][i] = input[1][i] + model.offset[i];
+            }
         }
     }
 }