Concatenate a folder using fluid.bufcompose

If windowing is needed, it can be done in many other objects after loading (hirt has one for instance) - I think I will vote that this object keeps doing what it does: sum 2 buffers to a 3rd one. With that and clever user-scripting, we have a new feature in max. Granularity of code is important and i think that sampling rate conversion and enveloping can be done elsewhere.