Remove un-needed mutex, up the latency

Author: OpenSauce

presets/metal.json

@@ -1,9 +1,9 @@
 {
-  "gain": 2.0,
+  "gain": 5.0,
   "drive": 50.0,
   "gate_threshold": 0.02,
   "lowpass_cutoff": 6000.0,
   "highpass_cutoff": 120.0,
-  "mode": "Polynomial",
-  "level": 0.5
+  "mode": "DiodeLike",
+  "level": 1
 }

src/amp.rs

@@ -103,17 +103,14 @@ impl Amp {
             DistortionMode::WaveFold => foldback(gated, 1.0),
         };
 
-        // Highpass filter (removing DC or very low freq)
         let highpassed =
             self.highpass_alpha * (self.highpass_prev + distorted - self.distorted_prev);
         self.distorted_prev = distorted;
         self.highpass_prev = highpassed;
 
-        // Lowpass filter (smooth out harshness at very high freq)
         let filtered = self.lowpass_prev + self.lowpass_alpha * (highpassed - self.lowpass_prev);
         self.lowpass_prev = filtered;
 
-        // Apply final level
         filtered * self.level
     }
 }

src/main.rs

@@ -5,7 +5,7 @@ use std::io::BufReader;
 use std::{
     env,
     sync::{
-        Arc, Mutex,
+        Arc,
         atomic::{AtomicBool, Ordering},
     },
     thread,
@@ -34,7 +34,7 @@ struct Args {
 
 fn main() {
     unsafe {
-        env::set_var("PIPEWIRE_LATENCY", "64/48000");
+        env::set_var("PIPEWIRE_LATENCY", "128/48000");
         env::set_var("JACK_PROMISCUOUS_SERVER", "pipewire");
     }
 
@@ -57,8 +57,7 @@ fn main() {
     let sample_rate = client.sample_rate() as f32;
     let amp = Amp::new(config, sample_rate);
 
-    let amp = Arc::new(Mutex::new(amp));
-    let (processor, writer) = Processor::new(&client, Arc::clone(&amp), recording);
+    let (processor, writer) = Processor::new(&client, amp, recording);
     let process = processor.into_process_handler();
 
     let _active_client = client

src/processor.rs

@@ -6,12 +6,12 @@ use rubato::{
 };
 use std::fs::File;
 use std::io::BufWriter;
-use std::sync::{Arc, Mutex, MutexGuard};
+use std::sync::{Arc, Mutex};
 
 pub type RecordingWriter = Option<Arc<Mutex<Option<WavWriter<BufWriter<File>>>>>>;
 
 pub struct Processor {
-    amp: Arc<Mutex<Amp>>,
+    amp: Amp,
     writer: RecordingWriter,
     in_port: Port<AudioIn>,
     out_l: Port<AudioOut>,
@@ -21,7 +21,7 @@ pub struct Processor {
 }
 
 impl Processor {
-    pub fn new(client: &Client, amp: Arc<Mutex<Amp>>, recording: bool) -> (Self, RecordingWriter) {
+    pub fn new(client: &Client, amp: Amp, recording: bool) -> (Self, RecordingWriter) {
         let in_port = client.register_port("in", AudioIn).unwrap();
         let out_l = client.register_port("out_l", AudioOut).unwrap();
         let out_r = client.register_port("out_r", AudioOut).unwrap();
@@ -53,7 +53,7 @@ impl Processor {
         let channels = 1;
         let oversample_factor: f32 = 2.0;
 
-        let max_chunk_size = 64;
+        let max_chunk_size = 128;
 
         let interp_params = SincInterpolationParameters {
             sinc_len: 256,
@@ -106,7 +106,7 @@ impl Processor {
         self,
     ) -> impl FnMut(&Client, &ProcessScope) -> Control + Send + 'static {
         let Processor {
-            amp,
+            mut amp,
             writer,
             in_port,
             mut out_l,
@@ -137,12 +137,9 @@ impl Processor {
                 eprintln!("Upsampler returned an empty buffer");
             }
 
-            {
-                let mut amp_guard: MutexGuard<'_, Amp> = amp.lock().unwrap();
-                let upsampled_channel = &mut upsampled[0];
-                for sample in upsampled_channel.iter_mut() {
-                    *sample = amp_guard.process_sample(*sample);
-                }
+            let upsampled_channel = &mut upsampled[0];
+            for sample in upsampled_channel.iter_mut() {
+                *sample = amp.process_sample(*sample);
             }
 
             let downsampled = match downsampler.process(&upsampled, None) {