This workflow turns text prompts into music using the ACE-Step 1.5 XL Base (4B) model inside ComfyUI. It pairs UNETLoader with the acestep_v1.5_xl_base_bf16.safetensors diffusion model and VAELoader with the ace_1.5_vae.safetensors decoder. Your prompt is encoded by TextEncodeAceStepAudio1.5, an EmptyAceStep1.5LatentAudio node creates a blank latent audio clip at your chosen duration, and KSampler performs the denoising pass to synthesize music. VAEDecodeAudio reconstructs the waveform from latents, and SaveAudioMP3 writes the final track to disk.
Under the hood, ConditioningZeroOut provides a clean fallback when the negative prompt is empty, while ModelSamplingAuraFlow configures the model’s sampler to the correct flow/schedule so KSampler can produce stable, on-style results. PrimitiveNode and PrimitiveInt nodes supply simple controls for duration, steps, guidance (CFG), and seed. The workflow is organized into clear groups (Model, Duration, Prompt) so you can quickly load the right weights, set the clip length, write a prompt, and iterate rapidly by adjusting steps, CFG, and seed.
API
Use this workflow from code
Every Comfy workflow is a JSON graph. The payload below is this workflow, exactly as ComfyUI runs it — fetch it from the URL, keep it in version control, or load it in ComfyUI and run it node by node.
GET https://comfy.org/workflows/download/536dc32faee1.jsonFetching workflow JSON…
Run it from Python or TypeScript with the Comfy SDK. The same code targets Comfy Cloud or a ComfyUI you host yourself — only the base URL changes.
# Install (beta)
pip install comfy-sdk # Python
npm i @comfyorg/sdk # TypeScript
# Run "ACE-Step 1.5XL Base: Text to Music" (Python)
from comfy_sdk import Comfy
client = Comfy(api_key="comfyui-...")
# This workflow, exported in API format (see note below)
wf = client.workflows.from_file("audio_ace_step1_5_xl_base_api.json")
job = client.run(wf)
for output in job.get_outputs("107"): # SaveAudioMP3
output.to_file(output.name)The SDK takes a workflow in API format: open this workflow in ComfyUI and use File → Export Workflow (API). API access requires a Comfy Cloud plan with an API key. SDK docs · Get an API key
FAQ
