Everything you need to know before your first conversion.
An arranger keyboard style file is a MIDI-based file that contains the auto-accompaniment data for a particular musical genre or rhythm. It includes multiple sections (intros, mains, fills, endings) each with separate MIDI tracks for drums, bass, chords, and melody. Yamaha uses .sty files, Korg uses .sty or .prs files, and Ketron uses .aks files.
Live conversion pairs are Yamaha→Korg, Yamaha→Ketron, and Korg→Ketron. Additional pairs are in development.
No. The conversion pipeline is fully automatic. You upload a file, select source and target keyboard models, and the engine does the rest. The review UI shows you the suggestions in plain language — you can approve everything with one click, or override individual mappings if something doesn't sound right.
Most conversions complete within 15–45 seconds depending on the complexity of the style and the number of sections. Priority processing (Pro and Studio plans) places your job at the front of the queue, typically reducing wait times to under 10 seconds.
Drum mapping
How the drum detection and remapping engine works.
Confidence is low when a source percussion note doesn't have a clear equivalent on the target keyboard. This commonly happens with proprietary ethnic percussion sounds, or with sounds that appear only occasionally in a style and don't match any known rhythmic template. These mappings are flagged for you to review and override.
DROP means that MIDI note will be silenced in the converted file — its events are removed entirely. This is the appropriate choice when a source sound has no reasonable equivalent on the target keyboard and any replacement would sound worse than silence.
Yes, on Pro and Studio plans. After confirming a conversion you are offered the option to save the drum mappings as a named drum map. On future conversions you can select this saved map from the dropdown and it will be applied automatically.
Yes, with caveats. The engine's three-pass approach identifies ethnic percussion channels correctly in most cases. Mapping quality depends on how closely the target keyboard's drum kit matches the source. For highly specialised sounds, some manual overrides in the review UI will usually be needed.
Root key detection
How chord root keys are detected and corrected.
Arranger keyboards use NTT (Note Transposition Tables) to respond to chord input and play chord voices in the correct key. If the root key is wrong, the chord voices play out of tune when you press keys on the keyboard. Correct root key detection ensures the converted style responds to your playing just like the original did.
Yes. In the Review UI, the root key detections table shows every section and channel with its detected key and confidence score. Click the override dropdown on any row to select the correct key. Your override is applied when you click "Confirm and generate file."
Some styles use chromatic chord voicings that don't imply a single root key. In these cases the analyser will report lower confidence scores and may detect different keys across sections. This is normal — the converted file will behave the same way.
Billing & plans
Subscriptions, credits, and payment questions.
One conversion is one uploaded style file processed through the full pipeline. The number of sections or tracks inside the file does not affect the count — it's per file. A conversion is counted when you click "Start conversion", regardless of whether you subsequently download the result.
No. Monthly conversions from your subscription plan reset on your billing renewal date. However, credit pack conversions never expire and are separate from your monthly allowance.
Yes. Cancel from your billing settings at any time. You keep full access until the end of your current billing period. No partial-month refunds are issued, and you will not be charged again after cancellation. Your account reverts to Free tier at the end of the period.
No. Once purchased, credit packs are non-refundable as per our terms of service. Unused credits in a pack never expire.
Not yet. Team plans with shared conversion pools and centralised billing are on the roadmap. If you need a volume arrangement now, contact us at [email protected] to discuss options.
Formats & compatibility
File format questions and known limitations.
No. rearranger.ai specifically processes arranger keyboard style files, which have a proprietary structure beyond standard MIDI. A regular MIDI file (.mid) cannot be converted because it lacks the section markers, CASM data, NTT tables, and other metadata that the conversion pipeline requires.
The converted style will play structurally identically — the same sections, the same rhythm and chord patterns — but the sound will reflect the target keyboard's internal voices. The musical content and groove are preserved; the timbre changes with the keyboard.
Both the original uploaded file and the generated output file are automatically deleted 24 hours after the conversion job completes. See our privacy policy for full details on data retention.
Still need help?
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