Members The Chinese Posted February 2, 2010 Members Share Posted February 2, 2010 Ok, So we all bow to the conventional wisdom that when arraying speakers, we should take into consideration the pattern control of each cabinet... but what I want to get into is the actual impact of all of this. For example, most of us run a Live sound PA in Mono - that is, we don't do a heck of a lot of panning or other spacial effects. So essentially, the signal coming out of both sides of a stack are identical. Yet we certainly don't try to splay the angle of the L-R stacks to worry about coverage; so therefore, by definition we will see comb filtering happen at some point within the audience. Why is this accepted, while having 2 90deg Enclosures considered such a bad idea? It would seem to me that the comb filtering effect would be more pronounced L-R as opposed to two speakers next to each other. I know the Haas Effect has something to do with this, in that the sounds coming after the initial sound get somewhat ignored by the brain. I'm more curious to know in a practical sense how much error to expect in a real world situation and how to minimize the impact, aside from not using a 90 deg box (we all already know that) Discuss... Todd Link to comment Share on other sites More sharing options...
Members Scodiddly Posted February 2, 2010 Members Share Posted February 2, 2010 One thing that does help in that typical setup is that the bulk of the audience is either in the pattern of one speaker or the other - sound from the other side will be attenuated by distance, people, etc. But yeah, that's the most common setup which isn't the best way. The best way is generally not something you can drag in and set up, though. A center cluster is always nice, but rigging in bars is not something you want your average bar band donig. Link to comment Share on other sites More sharing options...
Members RoadRanger Posted February 2, 2010 Members Share Posted February 2, 2010 The couple times I set up some 90 degree cabs at a 45 degree splay I purposely pointed out to a few folks the combing without telling them it's "bad" and they all thought it was a cool special effect . I'll betcha a tie dye shirt and a glow stick your "burner" friends would think the same way about it . Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted February 2, 2010 CMS Author Share Posted February 2, 2010 If you aren't using multiple boxes per side, there's nothing wrong with using 90-degree boxes. You need to get sound to the middle of the room, and no arrangement will ever be acoustically perfect. There's no practical difference in using a 90D box facing straight out, and using a 60D box canted inward to cover the center. In each case the sound arrives at a given pair of ears at slightly different times. How much from each speaker depends where you are in the room. Luckily our brains are quite used to sorting out the crap that our ears pass along. If the room is acoustically awful, you may have significant buildups and cancellations. You can't remove them completely no matter what gear you have. Link to comment Share on other sites More sharing options...
Members The Chinese Posted February 2, 2010 Author Members Share Posted February 2, 2010 I doubt it, considering that most of my "burner" friends are heavy hitters in the Entertainment Industry, and amongst some of the most talented people I know in the Lighting, Costuming, Video, Gaming, Fashion, and Photography industries. And FYI, Glow sticks are frowned on- environmentally irresponsible. Link to comment Share on other sites More sharing options...
Members agedhorse Posted February 2, 2010 Members Share Posted February 2, 2010 Because it isn't as big of a deal as many would like to believe it is. If you didn't cover with both sides (other than a center cluster of course), the ear's binural hearing would FEEL lopsided or out of relative balance. You also nee to insure adequate coverage which if you draw graphicly, will see that there will always be overlap. It's not a bad thing unless it's done without regard for the tradeoffs. Link to comment Share on other sites More sharing options...
Members The Chinese Posted February 2, 2010 Author Members Share Posted February 2, 2010 If you aren't using multiple boxes per side, there's nothing wrong with using 90-degree boxes. You need to get sound to the middle of the room, and no arrangement will ever be acoustically perfect. There's no practical difference in using a 90D box facing straight out, and using a 60D box canted inward to cover the center. In each case the sound arrives at a given pair of ears at slightly different times. How much from each speaker depends where you are in the room. Luckily our brains are quite used to sorting out the crap that our ears pass along. If the room is acoustically awful, you may have significant buildups and cancellations. You can't remove them completely no matter what gear you have. OK, but what about when more SPL is desired- I see all kinds of things done that are deemed "Horrible", but perhaps as RoadRanger pointed out, to the average joe, maybe it's not an issue? For example, let's say I DO put 2 90 deg boxes right next to each other. The comb filtering will change as I move, in any axis, but if they are tight packed enough, as I get further out the response should smooth out- I see this get done often- people will place 4 or more 2x15 cabs right next to each other, just to get things to pound. Sounds bad up close, but get further away, things sound OK. Do we overthink this stuff? Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted February 2, 2010 CMS Author Share Posted February 2, 2010 Yes. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted February 2, 2010 CMS Author Share Posted February 2, 2010 As Andy wrote, it's not as big a deal as many make it out to be. No matter what there are going to be problems and compromises must be made. If your audience expects 105dB at the back wall, and you need to stack boxes to achieve this, what is your alternative? "Sorry, I can't do this show for you, since the comb filtering will be severe". No, you aren't going to do that. I hope. You'll worry, and nobody else will. Obviously, you don't completely ignore the issue. Move the boxes, adjust EQ to where you have as good a compromise as possible for the room, and be happy. Link to comment Share on other sites More sharing options...
Members RoadRanger Posted February 2, 2010 Members Share Posted February 2, 2010 I doubt it, considering that most of my "burner" friends are heavy hitters in the Entertainment IndustryI feel for you - I'm lucky that my audiences just want to have a good time and don't listen with their eyes And FYI, Glow sticks are frowned on - environmentally irresponsible. I'd think with all the generators running at BM the glowsticks would be the least of the pollution issues . Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted February 2, 2010 CMS Author Share Posted February 2, 2010 I'd think with all the generators running at BM the glowsticks would be the least of the pollution issues . Link to comment Share on other sites More sharing options...
Members The Chinese Posted February 2, 2010 Author Members Share Posted February 2, 2010 I feel for you - I'm lucky that my audiences just want to have a good time and don't listen with their eyes :freak:I'd think with all the generators running at BM the glowsticks would be the least of the pollution issues . Bio-Diesel, Dude All the large installations are running on BD. That and there's an initiative called Green Man or Coolign Man, in which one can figure out the Carbon offset of his BM Theme Camp Hehe. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted February 2, 2010 CMS Author Share Posted February 2, 2010 Bio-Diesel, Dude All the large installations are running on BD. That and there's an initiative called Green Man or Coolign Man, in which one can figure out the Carbon offset of his BM Theme Camp Hehe. Bio-Diesel still pollutes. Even B100. Link to comment Share on other sites More sharing options...
Members The Chinese Posted February 2, 2010 Author Members Share Posted February 2, 2010 Bio-Diesel still pollutes. Even B100. So does farting. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted February 2, 2010 CMS Author Share Posted February 2, 2010 So does farting. So enjoy the glo-sticks. How else will you illuminate the bottom of the airshaft of a large casino as you rappel down a thin wire? Hmmm? Gonna light farts? Link to comment Share on other sites More sharing options...
Members The Chinese Posted February 2, 2010 Author Members Share Posted February 2, 2010 So enjoy the glo-sticks. How else will you illuminate the bottom of the airshaft of a large casino as you rappel down a thin wire? Hmmm? Gonna light farts? There's lots of ways to do that- A) ElWire.B) LED LightsC) Headlamp Seriously, Glo sticks as used for a specific reason are fine- Used as decoration when other options are avail- well that's an environmental mess. The chemicals used in them are quite nasty as well. As for power/Gennies - At current technologies, Battery power is almost impossible without huge expense, same with Solar (although there is a solar Camp at BM that gifts Solar power to anyone who needs it). We do use Solar Panels to charge many of our basic light needs in out living areas. now back to comb filtering!!!! Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted February 2, 2010 CMS Author Share Posted February 2, 2010 Glow-sticks....and farting, are more dangerous than comb filtering Link to comment Share on other sites More sharing options...
Members Coaster Posted February 2, 2010 Members Share Posted February 2, 2010 batteries are a chemical/gas disaster. oxygen is a far worse pollutant than carbon. these people are tricking you to fund an international political entity based on taxing one of the basic building blocks of life. dont take my word for it, research it before you write me off as a kook. i dare you Link to comment Share on other sites More sharing options...
Members The Chinese Posted February 2, 2010 Author Members Share Posted February 2, 2010 batteries are a chemical/gas disaster. oxygen is a far worse pollutant than carbon. these people are tricking you to fund an international political entity based on taxing one of the basic building blocks of life.dont take my word for it, research it before you write me off as a kook. i dare you I wouldn't. And nobody's tricking me. As I said in my previous post, Battery technology isn't there yet. I believe in balance, and taking small steps. Besides this isn't HCPP Forum, can we get back on topic? T Link to comment Share on other sites More sharing options...
Members agedhorse Posted February 2, 2010 Members Share Posted February 2, 2010 Oxygen can kill many bacteria. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted February 2, 2010 CMS Author Share Posted February 2, 2010 And FYI, Glow sticks are frowned on- environmentally irresponsible. Link to comment Share on other sites More sharing options...
Members Shaster Posted February 2, 2010 Members Share Posted February 2, 2010 My personal evolutional comb filtering experiences. Never used to be worried about comb filtering. First PA was two stacks of six speakers each - comb filter heaven. Used convential one horn/mid/bass bin PA's for years and not much thought on comb filtering. Then a while back I was on a few gigs where a fellow placed two Mackies side by side. The sound was beyond terrible. I did more research on the subject and became a comb filter fanatic. Then I did a gig where a fellow placed two Mackies side by side and it actually sounded very good (quite a feat). got me thinking. For a while now, agedhorse has been pointing out that a little knowledge is a dangerous thing re: comb filtering. So my current state is that if it sounds bad it is bad, and if it sounds good, it is good. I just don't have the tools, time and knowledge to predict if comb filtering is going to be a problem. So my current position is be aware, but be happy - unless it ain't workin'. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted February 2, 2010 CMS Author Share Posted February 2, 2010 My personal evolutional comb filtering experiences.Never used to be worried about comb filtering. First PA was two stacks of six speakers each - comb filter heaven. Used convential one horn/mid/bass bin PA's for years and not much thought on comb filtering. Then a while back I was on a few gigs where a fellow placed two Mackies side by side. The sound was beyond terrible. I did more research on the subject and became a comb filter fanatic.Then I did a gig where a fellow placed two Mackies side by side and it actually sounded very good (quite a feat). got me thinking.For a while now, agedhorse has been pointing out that a little knowledge is a dangerous thing re: comb filtering.So my current state is that if it sounds bad it is bad, and if it sounds good, it is good. I just don't have the tools, time and knowledge to predict if comb filtering is going to be a problem.So my current position is be aware, but be happy - unless it ain't workin'. I think you're right on the money here....A practical approach that uses some common sense and knowledge. I doubt anyone can accurately predict a problem with this, but just being aware that what you're hearing could be comb filtering is enough to get you from "sounds bad" to sounds good" in as short a time as possible. Link to comment Share on other sites More sharing options...
Members agedhorse Posted February 2, 2010 Members Share Posted February 2, 2010 One contributing factor with regard to comb filtering is that it's more likely to be objectionable if the off-axis polar patterns are not very uniform. Link to comment Share on other sites More sharing options...
Members The Chinese Posted February 2, 2010 Author Members Share Posted February 2, 2010 One contributing factor with regard to comb filtering is that it's more likely to be objectionable if the off-axis polar patterns are not very uniform. Is this somethign that one can read from Spec's or only avail with practical experience with a speaker? T Link to comment Share on other sites More sharing options...
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