Jörn Nettingsmeier <netti...@stackingdwarves.net> a écrit : > On 07/10/2011 03:41 AM, Marc Lavallée wrote: > > I'm waiting for a pair of > > very directional speakers that should (hopefully) help me enjoy > > conventional stereo. > > then the manger might be for you: > http://manger-msw.de/index.php?language=en > > this is a speaker that has been optimized for very good impulse > response behaviour (at the expense of almost everything else).
Then a fast amplifier is required. > in addition to its quick reaction, it's beaming like mad, which means > that it practically eliminates early reflections over a wide band (a > lot wider than conventional dome tweeters). its stereo reproduction > is stunning. That's the idea: instead of adding tons of acoustic treatment in my listening room, I prefer to invest in directive speakers. > if you can do with very little efficiency (sorry tube amp fans) The sensitivity of Manger speakers is about 88dB; that's not so bad. > and don't mind around 10% THD in the low frequencies (which is not as > bad as it sounds, but also not as good as manger make it sound), Most listeners can't detect 10% THD if the level of the distorted signal is low compared to the non-distorted signal. > then you should try it. I can't try Manger speakers since they are not distributed in North America. Also, I can't afford them. I already made my choice, and it's a horn based loudspeaker. Good enough compression drivers are cheap; the magic (and the money) is in the horn. > which none of the above claims to do. home listeners are consumers. > there is no point in promoting something to consumers when (as you > point out) there is no product. you have to promote it to _producers_. Right. But I'm a listener, not a consumer. I'm not a producer, but I might become a non-professional one, when I'll have a working ambisonics system at home. Why is Ambisonics well known in the scientific community and not much elsewhere? Why and how to promote Ambisonics to hobbyists and poor students who don't have access to institutional labs and studios? Are they a lost cause? With Internet, we now can do things differently without the classic producer/consumer mediation. If your target audience is only the producers, Ambisonics will just be patented again and sold under new names; it's just a matter of finding new tricks related to Ambisonics. I know that's exactly what you're trying to avoid... I will follow your tutorial to install my home system; without it, I'd be lost. Your other tutorial (for producer) shows Ambisonics as a spatialization tool for rendering stereo and 5.1 outputs; as a "consumer" (I hate this word), why would I want to install a 10 speakers periphonic system if producers just keep their amb files as masters? There's a missing link... > > If you could help me understand spherical harmonics, I'd be a "MAG > > fanboy" in no time. > > anyone who can grasp m/s stereo can grasp arbitrary order ambisonics. > i'm talking "understand the principle", not "grok all the > calculations and their implications to the nth degree". I grasp it, but I don't understand it. After reading many articles, I'm still lost, and I think it's important to understand part of the maths. HOA sounds like a nice marketing acronym (it carries a lot of mysticism and good vibes), but I can't just "believe"... > > The best didactic resource I found is a very > > strange article titled "Notes on Basic Ideas of Spherical > > Harmonics". It's so good that I barely understand 10% of it. > > isn't that a text by robert greene? i think i've read it. yeah, mr > greene is a mathematician, and they like it rigorous. It's a fine text, but it reminded me how little math education I had. > but you don't need that level of understanding to use ambisonics. you > don't have to understand electronics to use an amplifier, and you > don't have to understand acoustics to use a microphone. some insight > helps, and the more you know the better, but being able to build some > piece of gear from scratch is not a prerequisite to get started. True: there's no need to understand just to "use". But it's always nice to know *why* to use! There's no satisfaction in being just a "user" (or a consumer). > check out the link i posted earlier, it tries to introduce the > concept of spatial sampling to practical sound engineers. there's one > (intentional) gap in the logic, in that it starts with the > kirchhoff-helmholtz integral (which strictly speaking is the basis > for wfs, not ambisonics) and then jumps to spherical sampling. it's > not 100% kosher from a mathematical POV, but hopefully easier to > understand. and as the order goes up, the area of correct > reproduction expands, so that it ultimately approaches the KH surface > from the inside. if you're in a hurry, there are slides as well, > which are a lot more compact: > http://stackingdwarves.net/public_stuff/linux_audio/tmt10/TMT2010_J%c3%b6rn_Nettingsmeier-Higher_order_Ambisonics-Slides.pdf I already read your aticles, they are really good to intuitively understand Ambisonics. I'll read them again and again, then try to review my old maths and learn new ones. Thanks! -- Marc _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
