[LAU] ecasound/nama signal path queries

Hi all, I have a few questions about using ecasound and/or nama with slightly more complex, 'non-linear' chains of audio effects. By this I mainly mean 'forking' chains - such as highpassing a signal and applying a delay loop to the high-frequency components of the sound, and a distortion to the rest, for example. This kind of thing would generally be straightforward enough to implement in hardware with physical cables, but elegant implementations in DSP seem rarer -- at least in linux. One of the reasons I am interested in ecasound is that I gather from its 'examples' webpage that it handles exactly this kind of thing quite elegantly: 'Ok, let's next do some parallel processing: two chains are created and the input and output files are connected to them. As a result, the input signal is processed with two sets of effects, and then mixed back together. You can create as many chains this way as you want.' ( http://www.eca.cx/ecasound/Documentation/examples.html#effects) However, I suspect that ecasound in its raw form could be somewhat unwieldy for the sort of work I'd like to do, so I'd like to be able to use nama instead. Would this sort of 'forking' signal chain be as easy to set up in nama as it seems to be in ecasound? Also, in nama, is it possible/easy to adjust and play with the effects path (and effect parameters) on the fly, without interrupting playback? Relatedly, another thing I'd like to be able to do is a delay effect, with effect(s) (i.e. filters or certain kinds of distortion, followed by a gain reduction) applied 'inside' the delay loop, such that the effect is recursively, cumulatively applied to the looped material. Might sound like a strange requirement, I know, but it's actually a fairly central effect to the kind of music I'd like to make (dub reggae). Unfortunately, this is difficult to achieve easily in Linux. Since no delay plugin that I know of includes the kind of internal effects that I want, the only way to achieve this is with some kind of 'circular' DSP chain, which most programs don't allow. Does anyone know if this kind of 'circular' DSP chain might be achievable in any way in ecasound - for example, by feeding a track's output back to itself? Any tips on achieving either of the above with other programs welcomed, too! Thanks, all! James