FAQ¶
File Upload & Storage¶
How do I upload files to use with Tonn API?
We provide a simple two-step process for uploading files:
1. Call our /upload endpoint with your file details to get secure upload URLs
2. Use the provided upload URL to send your file
The endpoint returns two URLs: - A signed URL for uploading your file - A readable URL to use in other API endpoints
Both URLs are valid for 1 hour. After processing, files are automatically cleaned up from our temporary storage.
What file formats are supported?
We support the following audio formats: - MP3 (audio/mpeg) - WAV (audio/wav) - FLAC (audio/flac)
Do I need to host the audio files myself?
No, you can use our /upload endpoint to temporarily store files for processing. However, if you prefer, you can still host files on your own cloud storage and provide public URLs in your API requests.
General Questions¶
What is Tonn?
Tonn API is RoEx's powerful, AI-driven audio production engine, designed for seamless integration into software, services, and platforms. With Tonn API Self-Service, you can easily integrate AI-powered multitrack mixing and mastering into your product without complex setup or high upfront costs.
RoEx’s technology is built on pioneering research from Queen Mary University of London. Tonn has been used to process over 2 million audio tracks since April 2023.
What types of audio processing does the API support?
Currently, Tonn API Self-Service provides API endpoints for mixing and mastering. We will be expanding our feature set for mix/master analysis and other use cases, so stay tuned for updates.
Additional audio processing features, including Mix Analysis and Audio Cleanup, are available to high-volume and enterprise customers. More information can be found here.
How much will it cost me to use the Tonn API?
Tonn API Self-Service operates on a credit-based system, allowing you to pay only for what you use, with volume discounts available. Please register for a Tonn API Self-Service account for further pricing details. You’ll receive 1,000 free credits to get started.
Credits are deducted each time you make an API request for a final audio track. Once you have purchased credits, you can continue to use the mixpreview and masteringpreview endpoints to request 30-second previews of mixed and mastered audio without charge.
What happens if I run out of credits?
If you run out of credits, your API requests will return an error response. You can easily top up your account with additional credits at any time via your dashboard. You can also enable Auto Top-Up to prevent service interruptions. This enables automatic re-billing, triggered when your balance falls below a threshold defined by you.
Do you offer any client libraries or SDKs?
Yes, we offer a Python client library called roex-python to make integrating with the Tonn API easier. You can install it using pip:
pip install roex-python
Find more details and usage instructions on the PyPI project page.
What support is available if I have technical issues or need help with my account?
If you encounter technical issues or have questions about your account, please reach out to us at support@roexaudio.com.
Can I upgrade to an enterprise plan later if my business grows?
Yes! We offer enterprise solutions for scaled use cases (over 500 mix/master requests per month). Get in touch with our partnerships team to discuss a tailored plan using this form: Tonn API for Enterprise.
Multitrack Mixing¶
Can I mix a whole multitrack at once?
Yes! You can mix a full multitrack session in one go using the Tonn API, provided it has a maximum of 32 tracks. If your session exceeds this limit, we recommend first mixing a subgroup (e.g., drums) before combining everything into the final mixdown.
What's the difference between an audio track and a stem?
Audio tracks are usually recordings of just one instrument. In a drum kit, you could have individual audio tracks for the kick, snare, cymbals, etc. These can be recorded in either mono or stereo.
Stems are stereo recordings sourced from mixes of multiple individual audio tracks, such as drums, vocals, and bass. For example, a drum stem will typically be a stereo audio file that sounds like all of the drum tracks mixed together (i.e., kick, snare, cymbals).
Can I get access to the audio effect settings used to mix my tracks?
Yes! We now provide access to the mix settings used in the processing of your tracks. Keep in mind that the audio effect settings we provide are unique to our proprietary signal chain, as all the DSP we use has been developed in-house. We've been able to make these settings work successfully in Ableton Live, Bitwig, and PreSonus Studio One DAWs.
Can I download the processed stems?
Yes! When you retrieve the final mix, you can also request the processed stems, meaning you’ll receive back your multitrack audio with our processing and effects. This can be useful for providing component audio stems to your collaborators or for sync licensing opportunities.
Where can I get multitracks to try out the API?
You can download free multitracks to test with on the Cambridge Music Technology website. Please note: these should not be used for commercial purposes and are solely for testing purposes.
I'm unhappy with the mix output, what can I do?
Please contact us via support@roexaudio.com, so we can investigate and provide a solution.
My mixed/mastered track link is dead, what happened?
The URL we provide for your mixed or mastered track is only valid for 24 hours.
Mastering¶
Can I master a track that I've already mixed myself?
Yes, you can. This feature is available through the Tonn API.
What loudness options are available using Tonn for mastering?
You have the option to have your track mastered to a desired loudness. With each mastering request, you can specify: - Low (≈ -16 LUFS) - Medium (≈ -14 LUFS) - High (≈ -10 LUFS without clipping)