diff --git a/Cargo.lock b/Cargo.lock
index 0daa718..bbef3b2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -11,6 +11,28 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "alsa"
+version = "0.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2562ad8dcf0f789f65c6fdaad8a8a9708ed6b488e649da28c01656ad66b8b47"
+dependencies = [
+ "alsa-sys",
+ "bitflags 1.3.2",
+ "libc",
+ "nix",
+]
+
+[[package]]
+name = "alsa-sys"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "db8fee663d06c4e303404ef5f40488a53e062f89ba8bfed81f42325aafad1527"
+dependencies = [
+ "libc",
+ "pkg-config",
+]
+
 [[package]]
 name = "anstream"
 version = "0.6.4"
@@ -71,6 +93,26 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
+[[package]]
+name = "bindgen"
+version = "0.68.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "726e4313eb6ec35d2730258ad4e15b547ee75d6afaa1361a922e78e59b7d8078"
+dependencies = [
+ "bitflags 2.4.1",
+ "cexpr",
+ "clang-sys",
+ "lazy_static",
+ "lazycell",
+ "peeking_take_while",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "rustc-hash",
+ "shlex",
+ "syn 2.0.39",
+]
+
 [[package]]
 name = "bit-set"
 version = "0.5.3"
@@ -86,12 +128,71 @@ version = "0.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "349f9b6a179ed607305526ca489b34ad0a41aed5f7980fa90eb03160b69598fb"
 
+[[package]]
+name = "bitflags"
+version = "1.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
+
+[[package]]
+name = "bitflags"
+version = "2.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "327762f6e5a765692301e5bb513e0d9fef63be86bbc14528052b1cd3e6f03e07"
+
+[[package]]
+name = "bumpalo"
+version = "3.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f30e7476521f6f8af1a1c4c0b8cc94f0bee37d91763d0ca2665f299b6cd8aec"
+
+[[package]]
+name = "bytes"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a2bd12c1caf447e69cd4528f47f94d203fd2582878ecb9e9465484c4148a8223"
+
+[[package]]
+name = "cc"
+version = "1.0.84"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0f8e7c90afad890484a21653d08b6e209ae34770fb5ee298f9c699fcc1e5c856"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "cesu8"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d43a04d8753f35258c91f8ec639f792891f748a1edbd759cf1dcea3382ad83c"
+
+[[package]]
+name = "cexpr"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6fac387a98bb7c37292057cffc56d62ecb629900026402633ae9160df93a8766"
+dependencies = [
+ "nom",
+]
+
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
+[[package]]
+name = "clang-sys"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c688fc74432808e3eb684cae8830a86be1d66a2bd58e1f248ed0960a590baf6f"
+dependencies = [
+ "glob",
+ "libc",
+ "libloading",
+]
+
 [[package]]
 name = "clap"
 version = "4.4.7"
@@ -123,7 +224,7 @@ dependencies = [
  "heck",
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.39",
 ]
 
 [[package]]
@@ -138,6 +239,97 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "acbf1af155f9b9ef647e42cdc158db4b64a1b61f743629225fde6f3e0be2a7c7"
 
+[[package]]
+name = "combine"
+version = "4.6.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "35ed6e9d84f0b51a7f52daf1c7d71dd136fd7a3f41a8462b8cdb8c78d920fad4"
+dependencies = [
+ "bytes",
+ "memchr",
+]
+
+[[package]]
+name = "core-foundation"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "194a7a9e6de53fa55116934067c844d9d749312f75c6f6d0980e8c252f8c2146"
+dependencies = [
+ "core-foundation-sys",
+ "libc",
+]
+
+[[package]]
+name = "core-foundation-sys"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e496a50fda8aacccc86d7529e2c1e0892dbd0f898a6b5645b5561b89c3210efa"
+
+[[package]]
+name = "coreaudio-rs"
+version = "0.11.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "321077172d79c662f64f5071a03120748d5bb652f5231570141be24cfcd2bace"
+dependencies = [
+ "bitflags 1.3.2",
+ "core-foundation-sys",
+ "coreaudio-sys",
+]
+
+[[package]]
+name = "coreaudio-sys"
+version = "0.2.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d8478e5bdad14dce236b9898ea002eabfa87cbe14f0aa538dbe3b6a4bec4332d"
+dependencies = [
+ "bindgen",
+]
+
+[[package]]
+name = "coremidi"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1a7847ca018a67204508b77cb9e6de670125075f7464fff5f673023378fa34f5"
+dependencies = [
+ "core-foundation",
+ "core-foundation-sys",
+ "coremidi-sys",
+]
+
+[[package]]
+name = "coremidi-sys"
+version = "3.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "79a6deed0c97b2d40abbab77e4c97f81d71e162600423382c277dd640019116c"
+dependencies = [
+ "core-foundation-sys",
+]
+
+[[package]]
+name = "cpal"
+version = "0.15.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d959d90e938c5493000514b446987c07aed46c668faaa7d34d6c7a67b1a578c"
+dependencies = [
+ "alsa",
+ "core-foundation-sys",
+ "coreaudio-rs",
+ "dasp_sample",
+ "jni 0.19.0",
+ "js-sys",
+ "libc",
+ "mach2",
+ "ndk",
+ "ndk-context",
+ "oboe",
+ "once_cell",
+ "parking_lot",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+ "windows 0.46.0",
+]
+
 [[package]]
 name = "crossbeam-deque"
 version = "0.8.3"
@@ -171,6 +363,12 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "dasp_sample"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0c87e182de0887fd5361989c677c4e8f5000cd9491d6d563161a8f3a5519fc7f"
+
 [[package]]
 name = "dm42"
 version = "0.1.0"
@@ -186,6 +384,12 @@ version = "1.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a26ae43d7bcc3b814de94796a5e736d4029efb0ee900c12e2d54c993ad1a1e07"
 
+[[package]]
+name = "equivalent"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
+
 [[package]]
 name = "fancy-regex"
 version = "0.11.0"
@@ -196,12 +400,130 @@ dependencies = [
  "regex",
 ]
 
+[[package]]
+name = "glob"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
+
+[[package]]
+name = "hashbrown"
+version = "0.14.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f93e7192158dbcda357bdec5fb5788eebf8bbac027f3f33e719d29135ae84156"
+
 [[package]]
 name = "heck"
 version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"
 
+[[package]]
+name = "indexmap"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d530e1a18b1cb4c484e6e34556a0d948706958449fca0cab753d649f2bce3d1f"
+dependencies = [
+ "equivalent",
+ "hashbrown",
+]
+
+[[package]]
+name = "jni"
+version = "0.19.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c6df18c2e3db7e453d3c6ac5b3e9d5182664d28788126d39b91f2d1e22b017ec"
+dependencies = [
+ "cesu8",
+ "combine",
+ "jni-sys",
+ "log",
+ "thiserror",
+ "walkdir",
+]
+
+[[package]]
+name = "jni"
+version = "0.20.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "039022cdf4d7b1cf548d31f60ae783138e5fd42013f6271049d7df7afadef96c"
+dependencies = [
+ "cesu8",
+ "combine",
+ "jni-sys",
+ "log",
+ "thiserror",
+ "walkdir",
+]
+
+[[package]]
+name = "jni-sys"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8eaf4bc02d17cbdd7ff4c7438cafcdf7fb9a4613313ad11b4f8fefe7d3fa0130"
+
+[[package]]
+name = "js-sys"
+version = "0.3.65"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "54c0c35952f67de54bb584e9fd912b3023117cbafc0a77d8f3dee1fb5f572fe8"
+dependencies = [
+ "wasm-bindgen",
+]
+
+[[package]]
+name = "lazy_static"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+
+[[package]]
+name = "lazycell"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "830d08ce1d1d941e6b30645f1a0eb5643013d835ce3779a5fc208261dbe10f55"
+
+[[package]]
+name = "libc"
+version = "0.2.150"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "89d92a4743f9a61002fae18374ed11e7973f530cb3a3255fb354818118b2203c"
+
+[[package]]
+name = "libloading"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b67380fd3b2fbe7527a606e18729d21c6f3951633d0500574c4dc22d2d638b9f"
+dependencies = [
+ "cfg-if",
+ "winapi",
+]
+
+[[package]]
+name = "lock_api"
+version = "0.4.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3c168f8615b12bc01f9c17e2eb0cc07dcae1940121185446edc3744920e8ef45"
+dependencies = [
+ "autocfg",
+ "scopeguard",
+]
+
+[[package]]
+name = "log"
+version = "0.4.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b5e6163cb8c49088c2c36f57875e58ccd8c87c7427f7fbd50ea6710b2f3f2e8f"
+
+[[package]]
+name = "mach2"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d0d1830bcd151a6fc4aea1369af235b36c1528fe976b8ff678683c9995eade8"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "memchr"
 version = "2.6.4"
@@ -224,6 +546,22 @@ dependencies = [
  "midly",
 ]
 
+[[package]]
+name = "midir"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a456444d83e7ead06ae6a5c0a215ed70282947ff3897fb45fcb052b757284731"
+dependencies = [
+ "alsa",
+ "bitflags 1.3.2",
+ "coremidi",
+ "js-sys",
+ "libc",
+ "wasm-bindgen",
+ "web-sys",
+ "windows 0.43.0",
+]
+
 [[package]]
 name = "midly"
 version = "0.5.3"
@@ -233,6 +571,177 @@ dependencies = [
  "rayon",
 ]
 
+[[package]]
+name = "minimal-lexical"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
+[[package]]
+name = "ndk"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "451422b7e4718271c8b5b3aadf5adedba43dc76312454b387e98fae0fc951aa0"
+dependencies = [
+ "bitflags 1.3.2",
+ "jni-sys",
+ "ndk-sys",
+ "num_enum",
+ "raw-window-handle",
+ "thiserror",
+]
+
+[[package]]
+name = "ndk-context"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "27b02d87554356db9e9a873add8782d4ea6e3e58ea071a9adb9a2e8ddb884a8b"
+
+[[package]]
+name = "ndk-sys"
+version = "0.4.1+23.1.7779620"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3cf2aae958bd232cac5069850591667ad422d263686d75b52a065f9badeee5a3"
+dependencies = [
+ "jni-sys",
+]
+
+[[package]]
+name = "nix"
+version = "0.24.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa52e972a9a719cecb6864fb88568781eb706bac2cd1d4f04a648542dbf78069"
+dependencies = [
+ "bitflags 1.3.2",
+ "cfg-if",
+ "libc",
+]
+
+[[package]]
+name = "nom"
+version = "7.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
+dependencies = [
+ "memchr",
+ "minimal-lexical",
+]
+
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+source = "registry+https://github.com/rust-lang/crates.io-index"
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+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "39e3200413f237f41ab11ad6d161bc7239c84dcb631773ccd7de3dfe4b5c267c"
+dependencies = [
+ "autocfg",
+]
+
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+checksum = "1f646caf906c20226733ed5b1374287eb97e3c2a5c227ce668c1f2ce20ae57c9"
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+]
+
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+dependencies = [
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+ "num-derive",
+ "num-traits",
+ "oboe-sys",
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+
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+checksum = "7f44155e7fb718d3cfddcf70690b2b51ac4412f347cd9e4fbe511abe9cd7b5f2"
+dependencies = [
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+
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+dependencies = [
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+ "parking_lot_core",
+]
+
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4c42a9226546d68acdd9c0a280d17ce19bfe27a46bf68784e4066115788d008e"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "redox_syscall",
+ "smallvec",
+ "windows-targets 0.48.5",
+]
+
+[[package]]
+name = "peeking_take_while"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "19b17cddbe7ec3f8bc800887bab5e717348c95ea2ca0b1bf0837fb964dc67099"
+
+[[package]]
+name = "pkg-config"
+version = "0.3.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26072860ba924cbfa98ea39c8c19b4dd6a4a25423dbdf219c1eca91aa0cf6964"
+
+[[package]]
+name = "proc-macro-crate"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f4c021e1093a56626774e81216a4ce732a735e5bad4868a03f3ed65ca0c3919"
+dependencies = [
+ "once_cell",
+ "toml_edit",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.69"
@@ -251,6 +760,12 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "raw-window-handle"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2ff9a1f06a88b01621b7ae906ef0211290d1c8a168a15542486a8f61c0833b9"
+
 [[package]]
 name = "rayon"
 version = "1.8.0"
@@ -271,6 +786,15 @@ dependencies = [
  "crossbeam-utils",
 ]
 
+[[package]]
+name = "redox_syscall"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4722d768eff46b75989dd134e5c353f0d6296e5aaa3132e776cbdb56be7731aa"
+dependencies = [
+ "bitflags 1.3.2",
+]
+
 [[package]]
 name = "regex"
 version = "1.10.2"
@@ -300,18 +824,56 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c08c74e62047bb2de4ff487b251e4a92e24f48745648451635cec7d591162d9f"
 
+[[package]]
+name = "rustc-hash"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
+
+[[package]]
+name = "same-file"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "93fc1dc3aaa9bfed95e02e6eadabb4baf7e3078b0bd1b4d7b6b0b68378900502"
+dependencies = [
+ "winapi-util",
+]
+
 [[package]]
 name = "scopeguard"
 version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
+[[package]]
+name = "shlex"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7cee0529a6d40f580e7a5e6c495c8fbfe21b7b52795ed4bb5e62cdf92bc6380"
+
+[[package]]
+name = "smallvec"
+version = "1.11.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4dccd0940a2dcdf68d092b8cbab7dc0ad8fa938bf95787e1b916b0e3d0e8e970"
+
 [[package]]
 name = "strsim"
 version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "73473c0e59e6d5812c5dfe2a064a6444949f089e20eec9a2e5506596494e4623"
 
+[[package]]
+name = "syn"
+version = "1.0.109"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72b64191b275b66ffe2469e8af2c1cfe3bafa67b529ead792a6d0160888b4237"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
 [[package]]
 name = "syn"
 version = "2.0.39"
@@ -323,6 +885,53 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "synth"
+version = "0.1.0"
+dependencies = [
+ "anyhow",
+ "cpal",
+ "midir",
+ "midly",
+]
+
+[[package]]
+name = "thiserror"
+version = "1.0.50"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f9a7210f5c9a7156bb50aa36aed4c95afb51df0df00713949448cf9e97d382d2"
+dependencies = [
+ "thiserror-impl",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "1.0.50"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "266b2e40bc00e5a6c09c3584011e08b06f123c00362c92b975ba9843aaaa14b8"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.39",
+]
+
+[[package]]
+name = "toml_datetime"
+version = "0.6.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3550f4e9685620ac18a50ed434eb3aec30db8ba93b0287467bca5826ea25baf1"
+
+[[package]]
+name = "toml_edit"
+version = "0.19.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b5bb770da30e5cbfde35a2d7b9b8a2c4b8ef89548a7a6aeab5c9a576e3e7421"
+dependencies = [
+ "indexmap",
+ "toml_datetime",
+ "winnow",
+]
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.12"
@@ -335,13 +944,169 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "711b9620af191e0cdc7468a8d14e709c3dcdb115b36f838e601583af800a370a"
 
+[[package]]
+name = "walkdir"
+version = "2.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d71d857dc86794ca4c280d616f7da00d2dbfd8cd788846559a6813e6aa4b54ee"
+dependencies = [
+ "same-file",
+ "winapi-util",
+]
+
+[[package]]
+name = "wasm-bindgen"
+version = "0.2.88"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7daec296f25a1bae309c0cd5c29c4b260e510e6d813c286b19eaadf409d40fce"
+dependencies = [
+ "cfg-if",
+ "wasm-bindgen-macro",
+]
+
+[[package]]
+name = "wasm-bindgen-backend"
+version = "0.2.88"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e397f4664c0e4e428e8313a469aaa58310d302159845980fd23b0f22a847f217"
+dependencies = [
+ "bumpalo",
+ "log",
+ "once_cell",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.39",
+ "wasm-bindgen-shared",
+]
+
+[[package]]
+name = "wasm-bindgen-futures"
+version = "0.4.38"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9afec9963e3d0994cac82455b2b3502b81a7f40f9a0d32181f7528d9f4b43e02"
+dependencies = [
+ "cfg-if",
+ "js-sys",
+ "wasm-bindgen",
+ "web-sys",
+]
+
+[[package]]
+name = "wasm-bindgen-macro"
+version = "0.2.88"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5961017b3b08ad5f3fe39f1e79877f8ee7c23c5e5fd5eb80de95abc41f1f16b2"
+dependencies = [
+ "quote",
+ "wasm-bindgen-macro-support",
+]
+
+[[package]]
+name = "wasm-bindgen-macro-support"
+version = "0.2.88"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c5353b8dab669f5e10f5bd76df26a9360c748f054f862ff5f3f8aae0c7fb3907"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.39",
+ "wasm-bindgen-backend",
+ "wasm-bindgen-shared",
+]
+
+[[package]]
+name = "wasm-bindgen-shared"
+version = "0.2.88"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0d046c5d029ba91a1ed14da14dca44b68bf2f124cfbaf741c54151fdb3e0750b"
+
+[[package]]
+name = "web-sys"
+version = "0.3.65"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5db499c5f66323272151db0e666cd34f78617522fb0c1604d31a27c50c206a85"
+dependencies = [
+ "js-sys",
+ "wasm-bindgen",
+]
+
+[[package]]
+name = "winapi"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
+dependencies = [
+ "winapi-i686-pc-windows-gnu",
+ "winapi-x86_64-pc-windows-gnu",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+
+[[package]]
+name = "winapi-util"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f29e6f9198ba0d26b4c9f07dbe6f9ed633e1f3d5b8b414090084349e46a52596"
+dependencies = [
+ "winapi",
+]
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
+
+[[package]]
+name = "windows"
+version = "0.43.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "04662ed0e3e5630dfa9b26e4cb823b817f1a9addda855d973a9458c236556244"
+dependencies = [
+ "windows_aarch64_gnullvm 0.42.2",
+ "windows_aarch64_msvc 0.42.2",
+ "windows_i686_gnu 0.42.2",
+ "windows_i686_msvc 0.42.2",
+ "windows_x86_64_gnu 0.42.2",
+ "windows_x86_64_gnullvm 0.42.2",
+ "windows_x86_64_msvc 0.42.2",
+]
+
+[[package]]
+name = "windows"
+version = "0.46.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cdacb41e6a96a052c6cb63a144f24900236121c6f63f4f8219fef5977ecb0c25"
+dependencies = [
+ "windows-targets 0.42.2",
+]
+
 [[package]]
 name = "windows-sys"
 version = "0.48.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "677d2418bec65e3338edb076e806bc1ec15693c5d0104683f2efe857f61056a9"
 dependencies = [
- "windows-targets",
+ "windows-targets 0.48.5",
+]
+
+[[package]]
+name = "windows-targets"
+version = "0.42.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e5180c00cd44c9b1c88adb3693291f1cd93605ded80c250a75d472756b4d071"
+dependencies = [
+ "windows_aarch64_gnullvm 0.42.2",
+ "windows_aarch64_msvc 0.42.2",
+ "windows_i686_gnu 0.42.2",
+ "windows_i686_msvc 0.42.2",
+ "windows_x86_64_gnu 0.42.2",
+ "windows_x86_64_gnullvm 0.42.2",
+ "windows_x86_64_msvc 0.42.2",
 ]
 
 [[package]]
@@ -350,53 +1115,104 @@ version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9a2fa6e2155d7247be68c096456083145c183cbbbc2764150dda45a87197940c"
 dependencies = [
- "windows_aarch64_gnullvm",
- "windows_aarch64_msvc",
- "windows_i686_gnu",
- "windows_i686_msvc",
- "windows_x86_64_gnu",
- "windows_x86_64_gnullvm",
- "windows_x86_64_msvc",
+ "windows_aarch64_gnullvm 0.48.5",
+ "windows_aarch64_msvc 0.48.5",
+ "windows_i686_gnu 0.48.5",
+ "windows_i686_msvc 0.48.5",
+ "windows_x86_64_gnu 0.48.5",
+ "windows_x86_64_gnullvm 0.48.5",
+ "windows_x86_64_msvc 0.48.5",
 ]
 
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.42.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "597a5118570b68bc08d8d59125332c54f1ba9d9adeedeef5b99b02ba2b0698f8"
+
 [[package]]
 name = "windows_aarch64_gnullvm"
 version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2b38e32f0abccf9987a4e3079dfb67dcd799fb61361e53e2882c3cbaf0d905d8"
 
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.42.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e08e8864a60f06ef0d0ff4ba04124db8b0fb3be5776a5cd47641e942e58c4d43"
+
 [[package]]
 name = "windows_aarch64_msvc"
 version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dc35310971f3b2dbbf3f0690a219f40e2d9afcf64f9ab7cc1be722937c26b4bc"
 
+[[package]]
+name = "windows_i686_gnu"
+version = "0.42.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c61d927d8da41da96a81f029489353e68739737d3beca43145c8afec9a31a84f"
+
 [[package]]
 name = "windows_i686_gnu"
 version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a75915e7def60c94dcef72200b9a8e58e5091744960da64ec734a6c6e9b3743e"
 
+[[package]]
+name = "windows_i686_msvc"
+version = "0.42.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "44d840b6ec649f480a41c8d80f9c65108b92d89345dd94027bfe06ac444d1060"
+
 [[package]]
 name = "windows_i686_msvc"
 version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8f55c233f70c4b27f66c523580f78f1004e8b5a8b659e05a4eb49d4166cca406"
 
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.42.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8de912b8b8feb55c064867cf047dda097f92d51efad5b491dfb98f6bbb70cb36"
+
 [[package]]
 name = "windows_x86_64_gnu"
 version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "53d40abd2583d23e4718fddf1ebec84dbff8381c07cae67ff7768bbf19c6718e"
 
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.42.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26d41b46a36d453748aedef1486d5c7a85db22e56aff34643984ea85514e94a3"
+
 [[package]]
 name = "windows_x86_64_gnullvm"
 version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b7b52767868a23d5bab768e390dc5f5c55825b6d30b86c844ff2dc7414044cc"
 
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.42.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9aec5da331524158c6d1a4ac0ab1541149c0b9505fde06423b02f5ef0106b9f0"
+
 [[package]]
 name = "windows_x86_64_msvc"
 version = "0.48.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ed94fce61571a4006852b7389a063ab983c02eb1bb37b47f8272ce92d06d9538"
+
+[[package]]
+name = "winnow"
+version = "0.5.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "829846f3e3db426d4cee4510841b71a8e58aa2a76b1132579487ae430ccd9c7b"
+dependencies = [
+ "memchr",
+]
diff --git a/Cargo.toml b/Cargo.toml
index 8fbe631..5a21d32 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,9 +5,10 @@ edition = "2021"
 
 [workspace]
 resolver = "2"
-members = ["midi"]
+members = ["midi", "synth"]
 
 [dependencies]
 anyhow = "1.0.75"
 clap = { version = "4.4.7", features = ["derive"] }
 fancy-regex = "0.11.0"
+
diff --git a/synth/Cargo.toml b/synth/Cargo.toml
new file mode 100644
index 0000000..c71d22b
--- /dev/null
+++ b/synth/Cargo.toml
@@ -0,0 +1,10 @@
+[package]
+name = "synth"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+anyhow = "1.0.75"
+cpal = "0.15.2"
+midir = "0.9.1"
+midly = "0.5.3"
diff --git a/synth/src/main.rs b/synth/src/main.rs
new file mode 100644
index 0000000..f636ef1
--- /dev/null
+++ b/synth/src/main.rs
@@ -0,0 +1,162 @@
+use std::{
+    f32::consts::PI,
+    sync::{Arc, Mutex},
+    thread,
+};
+
+use anyhow::Result;
+use cpal::traits::{DeviceTrait, HostTrait, StreamTrait};
+use midir::MidiInput;
+use midly::{live::LiveEvent, MidiMessage};
+
+fn main() -> Result<()> {
+    let input = MidiInput::new("42synth input")?;
+    let ports = input.ports();
+    let port = ports.iter().next().ok_or("No ports found").unwrap();
+    let port_name = input.port_name(&port)?;
+
+    println!("Opening connection with `{port_name}`");
+    let synth = Arc::new(Synth::new());
+    let _connection = input.connect(&port, "42synth", on_event, synth.clone())?;
+
+    let host = cpal::default_host();
+    let device = host.default_output_device().unwrap();
+    println!("Default output device: {}", device.name().unwrap());
+
+    let mut supported_configs_range = device.supported_output_configs().unwrap();
+    let supported_config = supported_configs_range
+        .next()
+        .unwrap()
+        .with_max_sample_rate();
+    let sample_rate = supported_config.sample_rate().0 as f32;
+
+    let stream = device
+        .build_output_stream(
+            &supported_config.into(),
+            move |data: &mut [f32], _: &cpal::OutputCallbackInfo| {
+                let mut voices = synth.voices.lock().unwrap();
+                // dbg!(&voices);
+                for sample in data.iter_mut() {
+                    *sample = 0.0;
+                    let mut i = 0;
+                    while i < voices.len() {
+                        let voice = &mut voices[i];
+                        if let Some(s) = voice.oscillator.next(sample_rate) {
+                            if voice.playing {
+                                *sample += s;
+                            }
+                            i += 1;
+                        } else {
+                            voices.remove(i);
+                        }
+                    }
+                }
+            },
+            move |err| eprintln!("an error occurred on output stream: {}", err),
+            None,
+        )
+        .unwrap();
+    stream.play()?;
+
+    loop {
+        thread::park()
+    }
+}
+
+struct Synth {
+    voices: Mutex<Vec<Voice>>,
+}
+
+#[derive(Debug)]
+struct Voice {
+    key: u8,
+    playing: bool,
+    oscillator: Oscillator,
+}
+
+#[derive(Debug)]
+struct Oscillator {
+    i: usize,
+    tone: f32,
+    duration: Option<usize>,
+}
+
+fn on_event(_time: u64, data: &[u8], synth: &mut Arc<Synth>) {
+    let event = LiveEvent::parse(data).unwrap();
+    match event {
+        LiveEvent::Midi { channel, message } => match message {
+            MidiMessage::NoteOn { key, .. } => {
+                println!("hit note {} on channel {}", key, channel);
+                synth.note_on(key.as_int());
+            }
+            MidiMessage::NoteOff { key, .. } => synth.note_off(key.as_int()),
+
+            _ => {}
+        },
+        _ => {}
+    }
+}
+
+impl Synth {
+    fn new() -> Self {
+        Self {
+            voices: Mutex::new(Vec::new()),
+        }
+    }
+
+    fn note_on(&self, key: u8) {
+        const NOTE_MAP: [(u8, f32); 11] = [
+            (76, 1000.0), // 9
+            (75, 888.0),  // 8
+            (74, 800.0),  // 7
+            (73, 727.0),  // 6
+            (71, 615.0),  // 5
+            (69, 571.0),  // 4
+            (68, 533.0),  // 3
+            (67, 470.0),  // 2
+            (66, 470.0),  // 2
+            (64, 421.0),  // 1
+            (62, 320.0),  // 0
+        ];
+
+        let note = match NOTE_MAP.iter().find(|(k, _)| *k == key) {
+            Some((_, v)) => *v,
+            None => return,
+        };
+
+        self.voices.lock().unwrap().push(Voice {
+            key,
+            playing: true,
+            oscillator: Oscillator::new(note),
+        });
+    }
+
+    fn note_off(&self, key: u8) {
+        let mut voices = self.voices.lock().unwrap();
+        let note = voices.iter_mut().rev().find(|v| v.key == key);
+        if let Some(i) = note {
+            i.playing = false;
+        }
+    }
+}
+
+impl Oscillator {
+    fn new(tone: f32) -> Self {
+        Self {
+            i: 0,
+            tone,
+            duration: None,
+        }
+    }
+
+    fn next(&mut self, sample_rate: f32) -> Option<f32> {
+        self.i += 1;
+
+        match self.duration {
+            Some(d) if self.i > d => return None,
+            _ => {}
+        }
+
+        Some((self.i as f32 * self.tone * 2.0 * PI / sample_rate).sin())
+    }
+}