# Doepfer A-104 Trautonium Formant Filter drillable.com › eurorack › makers › doepfer-de › a-104. As of the capture of 9 Sep 2026; the index built 17 Sep 2026, 21:11 UTC · [cites, never asserts](/standing). Source: https://doepfer.de/a100_man/A104_man.pdf · quotes only, no licence recorded. Search `/eurorack/makers/doepfer-de/a-104?q=…` · MCP https://mcp.drillable.com · [html](/eurorack/makers/doepfer-de/a-104?format=html) · [markdown](/eurorack/makers/doepfer-de/a-104?format=md) · [json](/eurorack/makers/doepfer-de/a-104?format=json) · [discovery](/.well-known/drillable.json) · [guide](/llms.txt) ## Records read from it (13) By drillable.com ([llm-extract/3](/standing#methods)); scored precision 1.00, recall 0.36 on the harness's last sample of 50. ### [a 104](/eurorack/makers/doepfer-de/a-104) (5 records) - **description** = replica of the Formant Filter of the "Mixtur Trautonium" by Oskar Sala · as [a 104 · a 104](/eurorack/makers/doepfer-de/a-104) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=73&end=166) · [sha256:c81962e482ce7ab8…](/hashes/sha256:c81962e482ce7ab8251f5e4057fa8442249f22bdc02a22f8aa2760b1b25976c8) - **architecture** = four parallel resonance filters with common input and output · as [a 104 · a 104](/eurorack/makers/doepfer-de/a-104) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=167&end=265) · [sha256:a849905083c43666…](/hashes/sha256:a849905083c4366694594cc3a9c33421032f3059087d6d84a0984ba5b4c2befd) - **controls** = input level for all filters is controlled by an attenuator · as [a 104 · a 104](/eurorack/makers/doepfer-de/a-104) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=511&end=574) · [sha256:ceeb17f1bd5848eb…](/hashes/sha256:ceeb17f1bd5848eb8110dff36b0f8e75e94e796c47eb784d1e51e1664f1e5906) - **website** = www.doepfer.com · as [a 104 · a 104](/eurorack/makers/doepfer-de/a-104) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=993&end=1091) · [sha256:c07e6aa28f845640…](/hashes/sha256:c07e6aa28f8456405eda1ccf1237fdbdf199fdf6b238fb3679727e9f2be0fc51) - **function** = used in the first place for the simulation of resonances · as [a 104 · a 104](/eurorack/makers/doepfer-de/a-104) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=3849&end=3922) · [sha256:a200a33489831f79…](/hashes/sha256:a200a33489831f7928728c866538953d9d1553560f2fee871a7b251c94fc3ae2) ### [audio in](/eurorack/makers/doepfer-de/a-104/audio-in) (1 record) - **io** = Common filter audio input · as [a 104 · audio in](/eurorack/makers/doepfer-de/a-104/audio-in) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=1533&end=1571) · [sha256:465c3d17ae567f82…](/hashes/sha256:465c3d17ae567f82acd369c0f2cdd33f3a0633bc0138c13ab3b4f7a3b20ae510) ### [audio out](/eurorack/makers/doepfer-de/a-104/audio-out) (1 record) - **io** = Common filter audio output · as [a 104 · audio out](/eurorack/makers/doepfer-de/a-104/audio-out) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=1572&end=1612) · [sha256:9100e83feab06a28…](/hashes/sha256:9100e83feab06a28cfb723e231dc7b8894889a7d43cc4fa65aa2939e1eb6cc3e) ### [frq](/eurorack/makers/doepfer-de/a-104/frq) (1 record) - **function** = Frequency control · as [a 104 · frq](/eurorack/makers/doepfer-de/a-104/frq) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=1338&end=1364) · [sha256:a2d5ac0a66db6df7…](/hashes/sha256:a2d5ac0a66db6df7153c9d009dd4d46e9b94573d9fb0a85b5c03acd3b423ca4c) ### [input level](/eurorack/makers/doepfer-de/a-104/input-level) (1 record) - **function** = Attenuator for audio input signal (effective for all filters) · as [a 104 · input level](/eurorack/makers/doepfer-de/a-104/input-level) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=1246&end=1323) · [sha256:0e5aff1c400e858b…](/hashes/sha256:0e5aff1c400e858bbb7e335e2e7914e82d9d6c61d99d2b87ef0bead37ba08fda) ### [level](/eurorack/makers/doepfer-de/a-104/level) (1 record) - **function** = Level control (share of the filter signal in the mix output) · as [a 104 · level](/eurorack/makers/doepfer-de/a-104/level) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=1447&end=1517) · [sha256:98046792736f78ef…](/hashes/sha256:98046792736f78ef71a3ea1952aed9d462ffcbf3e6f0342b1372dab425b32793) ### [mode](/eurorack/makers/doepfer-de/a-104/mode) (1 record) - **function** = Mode switch (band/off/low) · as [a 104 · mode](/eurorack/makers/doepfer-de/a-104/mode) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=1411&end=1446) · [sha256:714a526983a56a22…](/hashes/sha256:714a526983a56a22fd866a323f1bf7a8624404097f1a6efd82d3859fef0defac) ### [resonance](/eurorack/makers/doepfer-de/a-104/resonance) (1 record) - **function** = Resonance control (Q, emphasis) · as [a 104 · resonance](/eurorack/makers/doepfer-de/a-104/resonance) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=1365&end=1410) · [sha256:702e4d5145892117…](/hashes/sha256:702e4d5145892117a4420c6ae87eeaba19e685d2918f32ba978d56e650d68c24) ### [vcf](/eurorack/makers/doepfer-de/a-104/vcf) (1 record) - **features** = can be switched to low pass or band pass or off · as [a 104 · vcf](/eurorack/makers/doepfer-de/a-104/vcf) · [quote](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b?trace&start=266&end=326) · [sha256:7dba073a1ff39a7f…](/hashes/sha256:7dba073a1ff39a7f906383b848d5db8360c46286d1e7f8e097a12741f7bfad53) ## Captures (1) - 9 Sep 2026, 00:04 UTC · https://doepfer.de/a100_man/A104_man.pdf · quotes only (no licence recorded) · 0 revisits · [text](/hashes/sha256:d6b99ad308a25d3e487ba2b34315e9b837e0bbde455c01c6912ff2d57211b38b) (pdfium/7881, 5643 bytes), [older text](/hashes/sha256:fbfa5ad7d9aa0afe439ec4ff3883acc4cb92b62cb67c40d674320c9aa1d4642d) (pdfium/7881, 12 bytes) · capture [sha256:7a97e6660c4e1e75…](/hashes/sha256:7a97e6660c4e1e75075751633733789e039705d37bb6ea3ae91b265cdae60e4c) A capture is what the source served at that moment; a later change at the source is a new capture, never an edit to this one. --- [standing](/standing) · Drillable™ is a trademark of Drillable LLC.