Additional frequencies?

[pcl]

According to the README, echoprint-codegen's algorithm processes samples at 11025 Hz. I'm interested in using additional frequencies to increase match accuracy, decrease the length of the sample required, and possibly handle recordings that are more active in lower frequencies.

So... I'm curious about the choice of 11025 Hz. Is there anything fundamental to the algorithm that depends on this choice of frequency? Are there things about lower or higher frequencies that make them less attractive, in your experience? Are there any constants etc. in the code that I should make parameterizable to properly handle other frequencies?