Convert CEL to SF2

Understanding CEL and SF2 file formats

CEL files are typically associated with Affymetrix microarray data, containing raw intensity values from gene expression experiments. These files are used primarily in bioinformatics and genomics research for storing and analyzing microarray results.

SF2 files, on the other hand, are SoundFont 2 files, a format used for storing instrument sounds, samples, and presets for use in MIDI synthesizers and digital audio workstations. SF2 files are widely used in music production for realistic instrument playback.

Is direct CEL to SF2 conversion possible?

There is no direct or standard method to convert a CEL file to an SF2 file, as these formats serve entirely different purposes—one for genetic data and the other for audio samples. A conversion would only make sense if you intend to use the data from a CEL file as a basis for generating audio samples, which would require significant data processing and sound design.

How to approach CEL to SF2 conversion

If you wish to use data from a CEL file in an audio context, you would need to:

1. Extract data from the CEL file using bioinformatics tools such as Affymetrix Power Tools or R/Bioconductor packages.
2. Convert the data into audio samples using audio programming environments like Audacity or MATLAB, by mapping data values to sound parameters.
3. Create an SF2 file from the generated audio samples using a SoundFont editor such as Polyphone or Vienna SoundFont Studio.

Recommended software for the process

• Affymetrix Power Tools or R/Bioconductor – for extracting and processing CEL data.
• Audacity or MATLAB – for converting data to audio samples.
• Polyphone (free, Windows/Mac/Linux) – for creating and editing SF2 SoundFont files.

Step-by-step workflow

1. Use Affymetrix Power Tools or R/Bioconductor to export CEL data to a readable format (e.g., CSV).
2. Import the data into Audacity or MATLAB and generate audio samples by mapping data values to sound properties.
3. Export the audio samples as WAV files.
4. Open Polyphone, import the WAV files, and create a new SoundFont (SF2) by assigning samples to instruments or presets.
5. Save the project as an SF2 file.

Conclusion

While there is no direct converter for CEL to SF2 due to their different purposes, you can creatively use bioinformatics and audio tools to transform data from a CEL file into a SoundFont (SF2) for experimental or artistic projects. Polyphone is the recommended software for creating SF2 files from audio samples.