Tweaking to achieve timbre matching is not something that I have ever seen offered on a speaker, as too much of this is tied to fixed design choices (drivers used, crossover network, enclosure size, ported vs. sealed). The LCR speaker will have a boundary compensation switch like the one offered on the Bookshelf in addition to the vertical/horizontal crossover network switch (there's even a picture of this here from HE 2007 ). It doesn't have the high frequency switch as far as I can tell, but I don't know that either the high frequency switch or the boundary compensation switch would be likely to help achieve timbre matching - the best bet is to find a center that is voiced similarly to the Allison's to begin with, and since I'm not familiar with their sound I have no idea what speaker might fit that bill.