On Mon, 20 Nov 2006 10:46:05 -0500 Gene Heskett <gene.heskett@xxxxxxxxxxx> wrote: > On Monday 20 November 2006 10:07, Sergei Steshenko wrote: > >On Mon, 20 Nov 2006 08:03:04 +0100 > > > >BISSON Frédéric <zigazou@xxxxxxx> wrote: > >> If possible I'd like 12 dB/octave because that's what the Gemini CX-1 > >> crossover has and it suits my needs. > > > >You probably know that a crossover made of 12db/octave LPF + HPF has a > >+3db bump at crossover frequency. > > > Mmm, does that not disappear when the vector additions are done, > disappearing due to the phase angle errors near the crossover freq? I'd say the opposite - it DOES appear because vector addition is done and there is a 90 degrees phase shift. Linkwitz-Riley crossover has filter that are in phase at crossover frequency, and they add up flatly. Linkwitz-Riley crossover LPF is two same Butterworth LPFs connected back to back, the same applies to HPH, LPF and HPF orders are the same, so Linkwitz-Riley crossover can be made of existing LADSPA plugins. All this is widely available knowledge; you can try running models in 'octave' or 'scilab' or simply find the info on the WEB. --Sergei. -- Visit my http://appsfromscratch.berlios.de/ open source project. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
