[linux-audio-announce] Mic-In-Room Simulator

Greetings to all, Announcing grad_Boxster for creating impulse response functions (IR's) for rectangular parallelepipeds --- for example concert halls modelled as giant boxes --- but using the *gradient* of the solution field projected on a direction specified by the user, similar to the operation of a pressure-gradient microphone --- in a room. At the URL below is a link to this package for downloading as well as a NON-optimized, alternating demo of grad_Boxster versus Boxster (i.e. "ordinary stereo versus binaural" or even "speakers versus headphones"): http://home.earthlink.net/~davidrclark grad2_Boxster is also available for simulating second-order mics in rooms. Extending grad_Boxster, the gradient of the first-order projection is computed and projected onto a second direction specified by the user. By combining IR's from Boxster (pressure mic), grad_Boxster (first-order mic), and grad2_Boxster (second-order), it should be possible to simulate any type of mic setup and combination of setups in any room that could be considered to be a box. Starting with dry, monophonic recordings made in a dead room, one should be able to simulate very sophisticated mic setups in a concert hall, then assemble them into a mix, simulating an ensemble recording, all with a physically consistent model. The demo contrasts simulation of nearly coincident pressure- gradient mics (grad_Boxster) in a 12,500 m3 concert hall versus binaural omni pressure mics (Boxster, no HRTF) in the same hall with the same separation between mics for both. The only difference for the first half of the demo is whether or not the gradient is computed, yet the sounds are very different both with speakers and with headphones (esp. the latter). In the second half, the positions of the guitars are slightly different (maximal separation for either). --------------------------- In short, grad_Boxster can be used to simulate ordinary stereo recordings (Blumlein, etc.) in the same manner that Boxster can be used for simulating binaural recordings, complete with reverb, echo, stereo separation, and so on --- but with physical consistency. As a side effect, both new programs provide other "knobs" for extending sample generation capability. All programs can be run either from a PyGtk GUI or from the command line. Regards to all, Dave Dave Clark