Target keyword: audio to MIDI Audio-to-MIDI conversion analyzes a recording and produces note events that can be edited in a piano roll. It can turn a hummed idea into a synth melody, help double a bass line, reveal the harmony of a sample or provide a starting point for transcription. The phrase “turn any melody into MIDI” needs one qualification: detection quality depends on the source. A clean single-note melody is easier than a full stereo mix. Pitch slides, vibrato, distortion, reverb, chords and drums introduce ambiguity. The best workflow combines automatic analysis with human review. HyperION Ultimate includes Track to MIDI inside the DAW, allowing detected notes to move directly into arrangement, sound selection and editing. ## What the conversion system listens for A note has pitch, start time, duration and intensity. Audio contains continuous changes rather than neat MIDI events, so an analyzer must decide when a note begins, which pitch best represents it, when it ends and whether a new event has started. The fundamental frequency suggests pitch, but many instruments contain stronger harmonics than fundamentals. A bass note may be detected one octave high. A breathy vocal may temporarily lose a clear pitch. Guitar bends and vocal slides travel between semitones instead of remaining at one keyboard key. Onset detection finds attacks, while pitch tracking follows the dominant note through time. The system then converts frequency to MIDI note numbers and estimates note lengths. Every step contains thresholds, which is why short false notes or split sustained notes can appear. ## Start with the simplest source Use a dry, isolated recording whenever possible. A solo vocal, bass, flute, lead synth or single-note guitar line is ideal. Reduce background noise and avoid clipping. If the melody exists only inside a full mix, use EQ or stem separation to reduce competing elements. [AI stem separation](https://www.hyperiondaw.com/blog/ai-stem-separation-guide) can make a melodic target clearer, though separation artifacts may create their own false notes. Choose a section with one musical idea and process that first. Analyzing an entire five-minute song creates more cleanup than learning from an eight-bar phrase. Once settings work, expand the range. ## Confirm tempo and alignment Set the project tempo before editing detected notes. If the source was recorded without a click, determine whether its tempo drifts. Forcing a live performance onto a rigid grid too early can destroy phrasing. Place the audio at a known bar and align its first intended attack. Keep the original track audible while editing MIDI. A waveform is useful, but the ear decides whether the note begins at the right musical moment. If tempo is unknown, tap along, identify repeated downbeats and test a short loop. A half-time or double-time estimate can still align beats while making the grid visually inconvenient, so choose the tempo that matches the musical subdivision. ## Run Track to MIDI Select the source track or clip, open Track to MIDI and choose the relevant analysis options. If the tool offers sensitivity, pitch range, scale or quantization controls, begin conservatively. Restricting the expected range can prevent octave errors. A bass part rarely needs the complete piano. A vocal analysis benefits from a range centered on the singer. Scale restriction can reduce impossible notes, but it should not erase intentional chromatic movement. Avoid strong quantization during detection. First capture the performance, then decide how much timing correction the new part needs. ## Compare note by note Solo the detected instrument with the original audio at a comfortable level. Begin at the first clear phrase and inspect: - missing attacks; - extra short notes; - octave jumps; - notes split by vibrato; - one detected note covering two performed notes; - note endings that overlap the next phrase; - velocity values that do not match emphasis. Correct pitch before choosing a final sound. A bright synth can hide some timing problems and exaggerate others. Use a simple piano or sine-like patch so note relationships remain obvious. ## Fix octave errors Octave errors are common because a harmonic may dominate the spectrum. If a note sounds correct in pitch class but wrong in register, move it by 12 semitones and compare. Do not automatically move every detected note together. A recording can alternate between correct and incorrect octaves. Look for sudden jumps that the original performance does not contain. Bass detection benefits from listening on speakers or headphones that reproduce low frequencies accurately. If the fundamental is weak, the analyzer may follow upper harmonics. A gentle low-pass filter on a duplicate analysis copy can sometimes help, but preserve the original audio track. ## Remove false notes Short notes often appear around consonants, pick noise, drum leakage or separation artifacts. Zoom in and compare with the waveform. Delete events that have no musical counterpart. Set a minimum useful duration only after understanding the style. Fast ornaments may be real. A blanket deletion of every short event can remove grace notes and rhythmic articulation. Repeated false notes at the same frequency may indicate hum, a resonant room tone or another instrument. Cleaning the source and analyzing again can be faster than deleting hundreds of events. ## Preserve or correct timing MIDI does not need to sit exactly on the grid to be useful. Human phrasing often places notes slightly ahead of or behind beat divisions. For a doubled synth, tighter timing may be required so the new sound reinforces the original. For a replacement performance, preserving the source timing may feel more natural. For a new arrangement inspired by the source, full requantization may be appropriate. Try quantizing note starts at a moderate strength while leaving endings flexible. Then adjust obvious outliers manually. Use the smallest grid that represents the phrase without turning every detail into a separate edit. ## Shape note lengths and velocity Detected duration describes the analyzer's view of continuous pitch, not necessarily the articulation a new instrument needs. Shorten overlapping notes for a monophonic synth. Extend notes for pads. Leave gaps when a bass patch needs clear attacks. Velocity should follow musical emphasis rather than waveform amplitude alone. Compression in the source may make every note similar in level even when the performance accents certain beats. Edit velocities as a phrase: identify the main accents, supporting notes and pickups. Randomization is not a substitute for performance. Deliberate patterns sound more human than arbitrary changes. ## Choose a sound after cleanup Once pitch and rhythm are reliable, select the instrument that serves the arrangement. A detected vocal melody can become: - a subtle synth double; - a string or brass response; - a bass countermelody; - a MIDI guide for harmony; - a visual reference for pitch correction. A guitar phrase can trigger a different articulation, but continuous bends may not translate without pitch-bend data. Recreate important slides manually or choose a sound that does not depend on them. Layering works best when each sound has a role. If the MIDI copy competes with the original, change octave, rhythm, timbre or section placement instead of simply turning both up. ## Convert chords carefully Polyphonic audio-to-MIDI is harder than monophonic detection because several pitches occur at once. Dense voicings, distortion and reverb create many overlapping harmonics. If Track to MIDI is optimized for melodies, separate chord work into smaller tasks. Identify the bass note first, then the top melody, then fill inner voices by ear. Slow the source without changing pitch if needed. For samples, determine whether the chord includes extensions or non-chord tones. Automatic output may prod
