☢ How to Create Base OTOs ☢

A comprehensive guide on writing base configuration files (otos) for UTAU and other DIY vocal synths. This resource assumes at least a basic knowledge of UTAU. If you need help with terminology or linguistic concepts, check the vocabulary page.

☆ What is a Base OTO? ☆

A base oto is a template for an UTAU voicebank configuration file, or oto.ini. Essentially, they do the work of splitting up a string into samples ahead of time so that this does not have to be done manually during the configuration process. They also often, but not always, provide numerical values for parameters with fixed values and rough estimates for those which will be adjusted later.

They are not meant to serve as a replacement for manual oto'ing; most samples will still need to be adjusted (human speech is imperfect, after all). Rather, they exist to make the process faster and easier.

There are a lot of benefits to creating a base oto, and they are not terribly difficult to set up. Having the samples already split into their own lines and named takes care of one of the more tedious parts of oto'ing, and if a certain parameter's value is going to be the same for every string, it can save a lot of time to have it already in place. This is especially true if you plan to use the same reclist for multiple voicebanks, multiple pitches in the same voicebank, or to release a reclist publically for other people's usage.