Hey, sorry for the delay on responding to this, and thanks for asking about xformer. xformer is a strange module, and I agree it’s not well documented – neither in the official documentation, nor within our internal notes. We are actively doing R&D for a newer, more suitable module to accomplish transformer-style saturation with clearer documentation/controls/sonic output, though I can’t comment on when that might be released to the public. There aren’t any sigfiles you can view which use the xformer module. For the time being, I recommend you keep area set constant to 1 and saturation set to -1. Then n1 becomes the number of primary turns (lower turns = the system saturates quicker, and the volume increases) and ratio can be used to match the output level (higher ratio = louder output). A quick technical note: xformer is only valid for a sample rate of 48k. Weird things can happen when you move off of 48k. We are actively working to fix this.
There is an interesting and computationally efficient approach to transformer saturation modelling here – https://www.ntnu.edu/documents/1001201110/1266017954/DAFx-15_submission_68.pdf. If I have some free time I might try to implement it in VSIG or RNBO
