ACE-Step 1.5 XL Save up to 17%ace-step-1-5-xl
Type
Spec
Rate
Music generation
per generated second
$0.0003$0.00025
ACE-Step 1.5 XL and Stable Audio 2.5 side by side: specs, capabilities, parameters, and live pricing from the EmpirioLabs catalog.
ACE-Step 
Stability AI Audio GenerationACE-Step 1.5 XL from ACE-Step and Stable Audio 2.5 from Stability AI are both in the Audio Generation category, available through the EmpirioLabs API.
| Spec | ACE-Step 1.5 XL | Stable Audio 2.5 |
|---|---|---|
| Model ID | ace-step-1-5-xl | stable-audio-2-5 |
| Author | ACE-Step | Stability AI |
| Released | Apr 2, 2026 | Sep 10, 2025 |
| Input | Text | Text |
| Output | Audio | Audio |
| Endpoints | POST /v1/audio/generations | POST /v1/audio/generations |
| Capabilities |
Live rates from the EmpirioLabs catalog for both models. Each rate card always matches what the API charges.
Request parameters each model lists on EmpirioLabs, with the allowed values or range where one applies. A dash marks a parameter the model does not list.
| Parameter | ACE-Step 1.5 XL | Stable Audio 2.5 |
|---|---|---|
| prompt | string | string |
| lyrics | string | - |
| audio_duration | 10 to 600 Default: 30 | - |
| num_inference_steps | 1 to 20 Default: 8 | - |
| guidance_scale | 0 to 20 Default: 1 | - |
| shift | number | - |
| seed | integer | number |
| format | flac, wav, ogg, mp3 Default: flac | - |
| response_format | url, b64_json Default: url | - |
| return_base64 | boolean Default: false | - |
| mode | - | text-to-audio, audio-to-audio, audio-inpaint Default: text-to-audio |
| output_format | - | mp3, wav Default: mp3 |
| duration | - | 1 to 190 Default: 190 |
| steps | - | 4 to 8 Default: 8 |
| cfg_scale | - | 1 to 25 Default: 1 |
| strength | - | 0.01 to 1 Default: 1 |
Supports lyrics, prompt/description, 10-600s duration, seed, shift, and URL or base64 output mode.
Adds audio-inpaint mode (regenerate a time window) on top of Stable Audio 2.0.
ACE-Step 1.5 XL runs through POST /v1/audio/generations. The request returns a job_id right away; poll GET /v1/jobs/{job_id} until the job completes and read the output URLs from the result. Both models are called through the same endpoint. Set model to ace-step-1-5-xl or stable-audio-2-5. Get an API key from the EmpirioLabs dashboard.
curl https://api.empiriolabs.ai/v1/audio/generations \
-H "Authorization: Bearer $EMPIRIOLABS_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "ace-step-1-5-xl",
"prompt": "Describe what you want ACE-Step 1.5 XL to generate."
}'Prompt tests and comparison runs that cover both models.
ACE-Step 1.5 XL is the newer release (Apr 2, 2026); Stable Audio 2.5 was released on Sep 10, 2025. Capabilities listed only for ACE-Step 1.5 XL: lyrics, text to music, seed control, commercial ready. Capabilities listed only for Stable Audio 2.5: text to audio, sound effects. The specs, rate cards, and parameters on this page come from the live EmpirioLabs catalog.
ACE-Step 1.5 XL is the newer release (Apr 2, 2026); Stable Audio 2.5 was released on Sep 10, 2025.
The two models are priced on different units or tiers, so compare the live rate cards on this page. They always match what the API charges.
Yes. Both models use POST /v1/audio/generations with the same EmpirioLabs API key, so most integrations switch by changing the model value. Check the parameters table on this page first if you rely on a model-specific parameter.
Yes. Open each model in the EmpirioLabs playground and run the same prompt on both, with the parameters the API exposes.
Check out our pricing or reach out if you want your own model deployed on our stack.
