> ## Documentation Index > Fetch the complete documentation index at: https://docs.unifically.com/llms.txt > Use this file to discover all available pages before exploring further. # Editing > Edit Suno clips: replace a section, crop, remove a section, fade, change speed, reverse, or stitch an extended song together. See parameters, pricing, and API examples. Edit an existing clip. Every operation returns a new clip and leaves the original untouched. All edits are free except **Replace Section**, which generates new audio. ## Models | Model | What it does | Billed | | ----------------- | ---------------------------------------------------------- | ------ | | `suno-ai/infill` | Regenerates a time range with new lyrics (replace section) | Yes | | `suno-ai/crop` | Keeps only a range, or removes a range | No | | `suno-ai/fade` | Adds a fade in, a fade out, or both | No | | `suno-ai/speed` | Changes tempo, optionally keeping pitch | No | | `suno-ai/reverse` | Reverses the clip | No | | `suno-ai/concat` | Stitches an extended clip into one full song | No | ## Replace Section Model: `suno-ai/infill` | Parameter | Type | Required | Description | | ------------------- | ------- | -------- | ---------------------------------------------------------------------------- | | `clip_id` | string | Yes | Clip to edit | | `mv` | string | Yes | Model version, see [Model Versions](/models/audio/suno/music#model-versions) | | `start_s` | number | Yes | Start of the section to replace, in seconds | | `end_s` | number | Yes | End of the section to replace, in seconds | | `lyrics` | string | No | Lyrics for the new section. Omit for instrumental | | `context_start_s` | number | No | Start of the surrounding context. Default: `start_s` | | `context_end_s` | number | No | End of the surrounding context. Default: end of the clip | | `tags` | string | No | Genre/style tags | | `title` | string | No | Title for the new clip | | `make_instrumental` | boolean | No | Replace with instrumental only | | `negative_tags` | string | No | Styles to avoid | Ranges that fall outside the clip are rejected before generation. Sections that start and end on bar boundaries blend best. ```bash theme={null} curl -X POST https://api.unifically.com/v1/tasks \ -H "Content-Type: application/json" \ -H "Authorization: Bearer YOUR_API_KEY" \ -d '{ "model": "suno-ai/infill", "input": { "clip_id": "1901ec96-72c6-4c26-8e56-91028ca6070d", "mv": "chirp-fenix", "start_s": 15, "end_s": 35, "lyrics": "Hello darkness, my old friend" } }' ``` ## Crop / Remove Section Model: `suno-ai/crop` | Parameter | Type | Required | Description | | --------- | ------- | -------- | ------------------------------------------------------------------------------------------------- | | `clip_id` | string | Yes | Clip to edit | | `start_s` | number | Yes | Range start in seconds | | `end_s` | number | Yes | Range end in seconds | | `remove` | boolean | No | `false` keeps only the range (crop). `true` cuts the range out (remove section). Default: `false` | | `title` | string | No | Title for the new clip | ```bash theme={null} curl -X POST https://api.unifically.com/v1/tasks \ -H "Content-Type: application/json" \ -H "Authorization: Bearer YOUR_API_KEY" \ -d '{ "model": "suno-ai/crop", "input": { "clip_id": "1901ec96-72c6-4c26-8e56-91028ca6070d", "start_s": 0, "end_s": 30 } }' ``` ## Fade Model: `suno-ai/fade` | Parameter | Type | Required | Description | | ------------ | ------ | -------- | ----------------------------------------- | | `clip_id` | string | Yes | Clip to edit | | `fade_in_s` | number | No\* | Fade-in length in seconds from the start | | `fade_out_s` | number | No\* | Fade-out length in seconds before the end | | `title` | string | No | Title for the new clip | \* Provide at least one of `fade_in_s` or `fade_out_s`. ```bash theme={null} curl -X POST https://api.unifically.com/v1/tasks \ -H "Content-Type: application/json" \ -H "Authorization: Bearer YOUR_API_KEY" \ -d '{ "model": "suno-ai/fade", "input": { "clip_id": "1901ec96-72c6-4c26-8e56-91028ca6070d", "fade_in_s": 3, "fade_out_s": 5 } }' ``` ## Speed Model: `suno-ai/speed` | Parameter | Type | Required | Description | | ------------------ | ------- | -------- | ----------------------------------------------------- | | `clip_id` | string | Yes | Clip to edit | | `speed_multiplier` | number | Yes | `0.25` to `4.0` | | `keep_pitch` | boolean | No | Preserve pitch while changing tempo. Default: `false` | | `title` | string | No | Title for the new clip | ```bash theme={null} curl -X POST https://api.unifically.com/v1/tasks \ -H "Content-Type: application/json" \ -H "Authorization: Bearer YOUR_API_KEY" \ -d '{ "model": "suno-ai/speed", "input": { "clip_id": "1901ec96-72c6-4c26-8e56-91028ca6070d", "speed_multiplier": 1.25, "keep_pitch": true } }' ``` ## Reverse Model: `suno-ai/reverse` | Parameter | Type | Required | Description | | --------- | ------ | -------- | ---------------------- | | `clip_id` | string | Yes | Clip to reverse | | `title` | string | No | Title for the new clip | ## Get Full Song Model: `suno-ai/concat` [Extend](/models/audio/suno/extend) returns only the new segment. Pass that extended clip here to receive one continuous song. | Parameter | Type | Required | Description | | --------- | ------ | -------- | ----------------------- | | `clip_id` | string | Yes | ID of the extended clip | ```bash theme={null} curl -X POST https://api.unifically.com/v1/tasks \ -H "Content-Type: application/json" \ -H "Authorization: Bearer YOUR_API_KEY" \ -d '{ "model": "suno-ai/concat", "input": { "clip_id": "e69f5332-af8d-489e-b6ce-4a08a7f6429a" } }' ``` ## Response ```json theme={null} { "code": 200, "success": true, "data": { "task_id": "abc123def456", "status": "processing" } } ``` The completed task returns `clips` with the edited result, the same shape as [Music Generation](/models/audio/suno/music). **Volume discounts** are available for almost all models. Reach out at [contact@unifically.com](mailto:contact@unifically.com) to discuss custom pricing.