Amen, brother! Your argument is further supported by the evolution of the state of high-power silicon. Once upon a time a 200w/c amplifier was a mammoth. There are power amplifiers now that can deliver 90%+ of the power available from the line to the load. These sorts of amps made their debut in bandwidth limited applications like subs, but have migrated all the way to full-band applications in recent years. While I might be inclined to generalise in describing them as "digital amplifiers," some are in fact, analog amps but with digital tracking power supplies. Quite recently I read about a multi-channel power amp for home theater applications that requires 2 x 15 A circuits. It delivers 7 channels capable of 300 w/c each. Things can be done with the express purpose of reproducing music, or for effect. Getting < 40 Hz seems to be more about effect. Michael --------- Original Message --------- Subject: Re: [Sursound] Infra sound & Sub bass From: "Richard Lee" <rica...@justnet.com.au> Date: 4/25/15 3:27 am To: "'Surround Sound discussion group'" <sursound@music.vt.edu>
The question isn't whether 'music' has frequencies below 1/zillion Hz. It's whether such content adds to the MUSIC. This is the case ONLY with organs reproduced properly. You can check this with DBLTs. The speaker that has come out top in every single DBLT it has been in nearly 2 decades (some dozen tests in all) was a small 6.5 ltr reflex with 70Hz cutoff. It was usually up against MUCH larger & expensive speakers. No one has complained about its bass though some remark it's a bit down. As we did ABC (33% chance if guessing) rather than ABX (50% chance) tests, the probability that this result is chance is extremely small. There's also a lot of myth about how to design speakers for "better defined & more energetic beat". None of this comes out in DBLTs and this little ported box with "terrible LF ringing" always has comments like "tuneful, well defined bla bla bass" attributed to it. Going from 70Hz to 40Hz cutoff will more than triple the size and cost of the speaker .. and to go to 20Hz will more than double that again. You need to decide if you are getting any MUSICAL gains. The organ example ... differentiating 'pressure in the head' and 'velocity' (trouser flapping) sensations is an important part of the MUSIC. For percussion in modern music (??!), Bruce Willis destroying the universe & other 21st century stuff, single subs are acceptable as they are all 'pressure in the head (and other parts of the anatomy)' sensations. Distributed subs fed with a mono signal allow this over a larger area. There's another myth that it's difficult to produce LF in small rooms. If all you want to do is dinosaur footsteps et al, this isn't the case. It's easier to pressurize a small room than a large one as you have to stuff less air in & out. But a similar sensation is obtained by having someone beat you over parts of your anatomy with a blunt instrument. In a large venue this is cost effective because the required staff are already there. They are called bouncers. What IS difficult is to produce Velocity (trouser flapping) at LF. You have to MOVE all the air in the room. I have no comment on mixes with loadsa stuff below 30Hz that overload the majority of playback systems without any MUSICAL benefit ... whether its to cheat a A-weighted meter or not. _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on. -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20150424/5bb7b6d8/attachment.html> _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
