Of course! (face palm)
Quite elegant, really...
ideal tube (stethoscope etc) --> 1 dimensional, with 0dB loss
ideal line (an ~infinite array) --> 2D, 3dB loss
other (horns, omni) --> 3D, 6dB loss
1) I have provided sound engineering for audiences of one (paying) person to free events with estimated audiences in the range of one million. In general, given "free range" an audience will naturally "fan out" in a 90 degree pattern. I have posted arial pictures of that effect in several posts.
1A) A single central sub can be used for any system that the listeners don't care about the lack of coherency in the crossover range other than in one specific location in the audience.
1B) I did not realize his audience members were small or skinny, but they all have reasonable hearing, don't they ;^) ?
2A) I described just a few out of thousands of systems I have either set up myself, or have heard over the years, many have been in excess of 6 x 45" bass horns cabinets wide.
2B) No, most occasions we placed the subs horizontally, 90" wide, and stacked up, the distance and coverage angle determining the array configuration.
2C) At the 200 Hz crossover used in the "old days" there was still a bit of low mid comb filtering, but that problem is quite low on the "totem pole" of live sound reinforcement, which makes the difficulties encountered in playback only systems seem like the difference between playing with building blocks compared to juggling live cats.
2D) Anybody can use a variety of interference prediction programs to "see" how spacing relates to any system. I can tell by looking at any proposed spacing what the positives and negatives will be, but can't tell you what the OP considers important, other than building a permanent, huge concrete edifice that will also produce prodigious amounts of bass, with many associated compromises.
3A) Although I have personally used and created "many tools of the trade" to form beam widths and wave patterns , I have not used digital delay or FIR based beam steering, though am quite familiar of their capabilities and limitations.
3B) That remains to be seen.
3C) Delays, beam steering or line arrays would not be necessary for the sub 100 Hz section of a relatively small outdoor system containing only one or two subs.
4) My recommendations were given in my reply in post # 67 to the OPs questions posed in post #56 and several before. He has thus far not commented on most of the salient points of my answers to his questions, and as i am not insane, don't expect that to change.
I have spent a lot of time answering a lot of questions in this thread, to some degree they were a therapeutic walk down memory lane just before and after reaching my sixth decade, of which 75% have been spent as a professional lighting and sound production engineer.
With limited time available, completing the many projects on my "to do" list won't allow much more time to contribute to this thread.
Auf wiedersehen,
Art
Hi Art,
OK. You get to take the rest of the night off. 🙂 Thanks for your interesting contributions.
Regards,
OK. You get to take the rest of the night off. 🙂 Thanks for your interesting contributions.
Regards,
Thanks for responding. Unfortunately there's not a single recommendation in this latest post or in post 67. The only actual direct recommendation I recall you making is to put the mains in the barn doors.
From the audience fanning to 90 degrees comment (which I assume means parallel to the stage as no other fanning pattern would seem to make sense) I can assure you, this does not ever happen at parties. Nobody at a party has ever lined up in a row with everyone to stare at the stereo system. They always cluster. Maybe not where you intend them to cluster, but they cluster and don't ever even look at the stereo system.
I understand that in a concert when there's something on the stage to look at the audience will fan out parallel to the stage and watch the show, but this has never in history and will never happen in a party setting (with the possible exception of a few minutes for a system demo).
From the fact that you think the audience is going to fan out and cover a larger area than OP expects and the fact that you don't seem to think that comb filtering is an issue, and the fact that you think that crossover issues trump lobing at subwoofer frequencies, I can safely infer that you vote for dual separated subs.
Dual separated subs will not fix anything at all and will actually make things a lot worse UNLESS the mains are inside the mouth of the sub, which is not something you have been advocating.
This is all really really simple.
One sub or two?
If two, how far apart are the subs?
What type of mains?
Where are the mains located?
The only question you have answered from those four questions is that the mains should be in the barn doors. You have also hinted heavily that there should be dual subs.
If there's dual subs the mains absolutely should be in the horn mouths - it doesn't make sense to put them anywhere else.
So full circle, the first question still has not been answered - single or dual subs.
In your opinion the benefits from dual subs outweigh the consequences. I still maintain that the benefits of a single sub dramatically outweigh the consequences. Looks like OP has some real world testing to do,
No, there's two in the bedroom, two in the fridge, three out the back having a smoke, one passed out in the corner.. 😉
Oliver,
OOps, my last "Live" story really happened, but Steve "Wally" Wallace was working for "Tool" when they took out the 400 amp 3 phase fuses, not "Live".
I did not enjoy the music of either band much at all, and can't remember anything about their music that would compel me to ever listen to it if I were not invited to see the show by an old friend.
One "Live" show that both me and Wally were invited to by Monte Lee Wilkes (R.I.P.) who was mixing them at the time, was outdoors, no power problems, even though there was a light mist of rain falling during most of day.
This was the kind of rain that concert promoters hate- not enough to collect rain insurance, but enough to keep most fans from bothering to come out to the show, which was near a river, the ground was pretty wet, serious rains the days before.
Big EAW "point and shoot" rig in arcs on 16' sound wings either side of stage. Several songs in to the set, Monty had cranked some bass and kick, and the song got all the kids pogoing in time. All of us on the FOH riser were all surprised that we could feel the earth moving rather substantially, like maybe 1/2 inch or more, real earthquake vibe. At first, we looked at each other like “holy crap, that’s some serious sub action!” - we could even see the FOH racks wobble a bit. However, I could feel it was not in time with the kick we were hearing exactly.
What was happening was the water table was so high that all the kids pounding the ground in unison was hydraulically bouncing us up and down back at the mix area when they hit the ground near the stage, an underground water wave!
“Live” went back to their more normal stuff, the rather small crowd stopped pogoing, and no more earth movement for the rest of the show.
Art
1) My recommendations given in my reply in post # 67 to the OPs questions posed in post #56 and several before don't recommend specific implementations because the OP has not provided any "weighting" as to his priorities (other than building concrete monuments), and unlike others, I feel no compulsion to impose mine on him. I also feel no compulsion to explain the whys and wherefores to unappreciative folks when I could be pursuing my own projects that may lead both to direct enjoyment as well as financial gain.
2) Your ASSumption again reveals your unbounded ignorance in spite of your obvious intellect. The "fanning out" is a comparison to a hand-held folding fan, which can be expanded and held at any desired angle.
3) Although I would "vote" for dual subs located directly beneath or surrounding the stereo mains, just as in the recent USA election, the only vote that counts is your own, in this case, the OP will eventually "vote" to do or not do whatever he wants. Other than my own personal desire to help folks make decisions they won't later regret, based on my personal regrets and the regrets of many I have worked for, I don't care what Entropy Eric decides to do- it will sound "good enough" with most whatever he does outside. That said, choices in the deployment of outdoor systems reveals shortcomings far easier than indoors, where they are masked by room reflections, modes, and nodes.
4)You continue imposing absolutes as if each decision is binary, again showing ignorance of the multiple aspects of sound propagation and perception that all should be carefully considered before committing to an expensive permanent installation.
5) Correct, until Entropy Eric decides what he wants to do, and then does it, your question will remain unanswered. If my health remains good, long before that occurs, I will have finished my birthday present to myself, a sail rig for my 12" FoldBote, built a pair of small subs for my home theater set up, built six Keystone "B-Low" cabinets that can and will be set up in dozens of mono, stereo, end fire, cardioid and "barn door" arrays, and have finished building several different variations of my SynTripP top cabinets that will be useful for a wide variety of applications to most anyone reading.
Below are some arial photos demonstrating people "fanning out" around sound systems, and a photo of the Alive in '85 WS PA system. People fanned out hours before the first act appeared, in a mad dash through the gates running across acres of land with lawn chairs, coolers and cameras under each arm, to the music of the William Tell Overture, better known as the theme song of the "Lone Ranger". Wish I had the videos I shot of that, but they were lost with hundreds of other archives when my ex-wife's house burnt to the dirt.
The 4 "block" WS We Fest "Alive in '85" system was less than 25% of the frontal area of the 16 block dB Sound/WS system described in a prior post, but satisfied the country rock audience at distances from the stage where performers looked the size of ants, roughly double the distance to the cheap seats at the Milwaukee Brewers Stadium. Sharp-eyed readers may recognize the Terry Hanley intercom on top the custom console doghouse, Hanley provided sound for Woodstock '69, for all I know that used intercom may have been used at that show too.
Continuing with Pogo dance stories, STS later provided production for what might now be called "Indie Rock" groups show at the same venue in Detroit Lakes Minnesota. When the band started really rocking, the dancers started to pogo, and at the FOH, (225 feet back) we asked “where did the punters go?”
Actually it was more like “WTF-!!”
The punters had started to dance in unison in the “celebrity seating” area, it had caved in, dropping dazed dancers between 6 to 8 feet, leaving upright posts standing like funeral pyres between shattered 4’x 8’ plywood remnants.
Not one of the hundreds of the dancing punters were hurt more than usual in the activities, they all crawled from the wreckage and the show went on, though the band lost the intimate feeling of the crowd, which was now separated by a moat of shattered plywood.
A good time was had by all, other than the cleanup/construction crew.
Cheers,
Art
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OP hasn't rated his goals in terms of importance on a scale of 1 to 10 in a top 10 list type laminated chart but it's pretty obvious what he is trying to accomplish and it's pretty easy to talk about the options to achieve the goal in the most technically correct fashion to give the best coverage over the very well defined audience area. It has nothing to do with imposing priorities (although your suggestion of audience fanning and your obvious disgust of OP's chosen audience area in your drunken post is about as close as you can get to imposing your priorities without actually telling him he's stupid), it's a discussion of how to handle real world challenges in a technically proficient manner.
A compliment and a personal insult in the same sentence. Cool.
Again I will assure you that this fanning out will NEVER EVER EVER happen at a party. Have you ever been to a party? (I mean one without some form of live entertainment.) In all the pics you showed there is a stage with stuff going on and all the people are looking directly at the stage and their chosen positioning best facilitates a view of the stage. The only goal of an audience member at a concert is a good view of the stage.
This is never going to happen when there is no stage, no band, no dj. There's nothing to look at, why would the party people fan out and stare at the stereo system? Never going to happen. So I guess it's you ASSumption that reveals that your unbounded ignorance in the context of social interactions means that not everything should be set up as a concert.
In fact at a party where there is a hot tub with the host sitting in it, I give 10/1 odds that the crowd will gather around or at least near to the hot tub, especially if the hot tub is the visual and acoustic center of the party. This is exactly what OP has outlined in his audience area pic.
First of all, the only permanent part of the installation is the concrete sub(s). The mains location can be easily changed at any time.
Second, if the mains are not vertically in line with the center of the sub(s) then there will be serious comb filter issues. If there are dual subs it is a binary right or wrong decision about mains placement - there's a right way and a wrong way.
You may have noticed that I have strongly pushed for a single sub and presented a huge amount of info to back up this perspective, but at no point did I say it was a binary decision - even after OP and others looked at the information and made a decision, I kept the discussion open by saying the discussion is not over as long as people continue to advocate dual separated subs.
Using dual subs with the mains placed to the side is the worst of both worlds - comb filtering all through the subwoofer frequencies and comb filtering between the subs and mains. With a single sub or dual subs with mains vertically in line with the sub centers at least some of this can be alleviated or eliminated.
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JAG,
Ignorance, as in ignoring facts presented, was not meant as a personal insult, sorry you took it that way, you ignorant Canadian 😉 .
1)Yes, I have been to a party or two, never have been to one with a huge concrete monument though- initially I'd have a hard time not facing it from where ever I was located, though that would wear off after a few drinks. At listening parties, the people invariably look in the direction they perceive the sound coming from.
If the party is not a listening party, people don't give a crap about the sound system.
2) See #1.
3) I have never been to a party hosted by a host in a hot tub, though I have been to an outdoor hot tub party in the snow In Minneapolis.
I owned a hot tub in New Mexico, and had a sound system surrounding it, the tub never was a focus at a party, other than guests did hang around it, as we had party food set up on the hot tub cover.
4)So glad you will allow the OP to decide what he will do, very gracious of you
.Cheers,
Art
Hi just a guy,
I snipped some lines re labhorns, from your post #190 in this thread....
"The horn (2, 12 inch drivers)
St = throat area = 80 sq ins (40 sq inches per driver)
Vb = rear chamber volume = 1530 cu in per driver (separate rear volumes for
each driver)
Vf = front chamber volume = 170 cu in per driver (volume between cone & throat)
Flare = 26.4 Hz, hyperbolic t = .5, path length = 126 inches (inc front volume).
Also, let's not forget that he hobbled the Labhorn design when he folded it with too small rear chambers."
***********************************************************
May I ask what you consider the optimal rear chamber volume?
I've thought about toying with this on my labhorns.....if I can simply space out the driver access covers to add enough volume...
Thanks! mark
I snipped some lines re labhorns, from your post #190 in this thread....
"The horn (2, 12 inch drivers)
St = throat area = 80 sq ins (40 sq inches per driver)
Vb = rear chamber volume = 1530 cu in per driver (separate rear volumes for
each driver)
Vf = front chamber volume = 170 cu in per driver (volume between cone & throat)
Flare = 26.4 Hz, hyperbolic t = .5, path length = 126 inches (inc front volume).
Also, let's not forget that he hobbled the Labhorn design when he folded it with too small rear chambers."
***********************************************************
May I ask what you consider the optimal rear chamber volume?
I've thought about toying with this on my labhorns.....if I can simply space out the driver access covers to add enough volume...
Thanks! mark
Fair enough, but the word ASSumption and "unbounded ignorance" in the same sentence sound like an insult regardless of what you attempted to imply.
It seems that the only (or at least the main) thing we don't agree on is this.
You seem adamant that the tone and pitch are going to walk across the soundstage at the frequencies immediately surrounding the crossover and this is the dominant issue, comb filtering is way down on the list of problems. (Incidentally, the ONLY way to fix this "walking" issue that you are insisting is going to be a problem is to have the mains directly on the vertical axis of the center of the sub, either in or above the center of the sub.)
I am adamant that there will be no tone or pitch walking if the mains are as close as possible to the center of the sub (which would be directly on either side of the single mono sub) and if a sufficiently low and steep crossover is used (for example 80 hz with at least 24 db/oct slope). In light of that, I suggest the comb filtering issues are the dominant problem and can only be solved using a single sub (if it's going to be as large as OP proposes).
Yes, I am fully advocating that OP makes his own decision on this (as I have from the beginning) by taking his stereo system outside and testing these two configurations.
I am not narcissistic enough to declare that my perspective is the best or will best match OP's preference (even if I've made statements that suggest this, as I sometimes exaggerate to make a point), this is why I've attempted to keep the single vs dual spaced sub positioning open at least until OP can do his own testing. On the other hand, I have provided a boatload of evidence that suggests that comb filtering using dual spaced subs will be a huge problem. Unfortunately I can't point to any evidence that the single sub approach with flanking mains on either side won't produce tone and timbre walking across the soundstage. All I can do is state that all empirical reports suggest that with a low crossover with steep slope the sub localization will be near imperceptible and this will not be an issue.
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As per the original Labhorn design (before folding) the chamber volume was 50 liters (25 liters per driver).
I don't know what the actual folded chamber size ended up being, but I do know it's significantly less than 50 liters. I think Danley suggested it was 9 liters smaller than planned after folding while Parham has suggested 16 liters smaller than planned. I don't know the correct answer but I can say that in sims, using Parham's figure matches the Lab measurements better.
The Lab lost some volume in the rear chamber and the flare when it was folded, IIRC the folded design is ~ 100 liters smaller than the design was spec'ed before folding, so it lost a lot of volume in the horn flare too. The horn flare volume loss isn't that important, but the rear chamber volume does make a pretty dramatic impact on the frequency response and I assume on the thermal aspect as well (power compression when pushed hard). If the original chamber size is used (instead of the shrunken chamber size in the plans) it goes a long ways towards getting rid of the big notch right above the low knee. Depending on your high pass filter, fixing that notch may or may not be important - an aggressive high pass gets rid of the notch by severely notching down the spike at the low knee, bringing that spike in response at the low knee down to the level of the dip.
I can send you Danley's Labhorn design notes if you like (the ones that I have anyway, they start near the end of the design process but are still useful in a variety of ways, I'm always posting sections of these notes even in discussions that have nothing to do with the Lab - there's a lot of wisdom in these notes and obviously a lot of info about the Lab design before and after folding). PM me your email address if you want me to send you the Labhorn notes.
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JAG,
I'm not adamant that either problem you mention are dominant issues either for myself or the OP, Entropy Eric.
Although you are entitled to "order" your listening "problems" any way you deem fit, they will make no difference to my listening perception whatsoever. I am quite aware of what I can, and can not hear, and aware that every individual has quite different "doors to perception".
I won't speak for the OP, he is fully capable of voicing whatever concerns he has, or ignoring any raised by anyone else, as he sees fit.
Ain't going to make any difference to me, he is not a client, and has not expressed any interest in becoming one
. Art
You have suggested exactly the opposite on several occasions. By voting for dual subs you are specifically saying comb filtering at subwoofer frequencies is not a dominant issue and tone and timbre walking is.
These are not "listening problems", they are design problems.
Again, I will point out (for perhaps the 20th time now) that if the tone and timbre of the sound around the crossover region does indeed walk around (which all empirical reports suggest is not going to happen with a low and steep crossover) the only way to fix it is to put the mains directly on the vertical axis of the center of the sub, either inside the sub at the horizontal center or above the sub at the horizontal center.
This is NOT what you recommended most recently by suggesting the mains should be off the the sides of the sub in the barn doors.
In a few cases your recommendations like the mains location in the barn doors recommendation I just mentioned have not followed what your "listening perception" says is important. And whether you want to admit it or not, addressing the things that you claim can be quantified by your listening perception directly speaks to the importance and dominance of the issues.
To the OP - this might all seem complicated and it can be hard to know who to listen to. Don't listen to anybody, do your own testing. Set your stereo up in your backyard in the two proposed configurations with a low crossover frequency setting and high slope and listen to it. Dual subs with 60 foot separation and mains placed directly on the sub vs single mono clustered sub with mains 16 feet to each side of the single sub.
The discussion here is centered on the importance of two issues. Comb filtering vs sound walking across the soundstage at frequencies around the crossover point. I am fairly confident that you will find the comb filtering to be a significant problem and you will not notice ANY issues with sound walking across the soundstage. Weltersys is confident you will find the opposite (several of his comments say this is true even if he outright denies it).
All of weltersys' comments in this discussion are about setting up your system the same way a large concert is set up, with a massive audience several times larger and most importantly wider than the stage. All of my comments are about setting your system to get the most even coverage over your clearly defined very small audience location.
Do the test and decide for yourself. Listen to it with real music and if you can measure the response with pink noise or frequency sweeps at all locations inside your defined audience area. You are Pepsi challenge kind of guy. Our comments and all the information provided should be used as a reference only and your own listening test should be the only real important data point.
Once you figure out which is more important (or even relevant at all) - comb filtering or soundstage walking around in your defined audience area - you will know the correct answer to the single or dual sub question. While it's true that the full size horn will beam at higher frequencies and your "little" home subs won't, this doesn't matter much (if at all) as long as you stay inside your small defined audience area - the large sub beam should cover most of your small audience area, especially with a low crossover frequency and steep slope.
After that everything is really simple. What type of mains and exactly where to position them. This isn't something you need a paid professional for (in fact there are no professionals that do this kind of system for a living - or ever - it's a very specialized system you have chosen), it's all stuff you can answer on your own with a little bit of empirical testing.
The discussion here is centered on the importance of two issues. Comb filtering vs sound walking across the soundstage at frequencies around the crossover point. I am fairly confident that you will find the comb filtering to be a significant problem and you will not notice ANY issues with sound walking across the soundstage. Weltersys is confident you will find the opposite (several of his comments say this is true even if he outright denies it).
All of weltersys' comments in this discussion are about setting up your system the same way a large concert is set up, with a massive audience several times larger and most importantly wider than the stage. All of my comments are about setting your system to get the most even coverage over your clearly defined very small audience location.
Do the test and decide for yourself. Listen to it with real music and if you can measure the response with pink noise or frequency sweeps at all locations inside your defined audience area. You are Pepsi challenge kind of guy. Our comments and all the information provided should be used as a reference only and your own listening test should be the only real important data point.
Once you figure out which is more important (or even relevant at all) - comb filtering or soundstage walking around in your defined audience area - you will know the correct answer to the single or dual sub question. While it's true that the full size horn will beam at higher frequencies and your "little" home subs won't, this doesn't matter much (if at all) as long as you stay inside your small defined audience area - the large sub beam should cover most of your small audience area, especially with a low crossover frequency and steep slope.
After that everything is really simple. What type of mains and exactly where to position them. This isn't something you need a paid professional for (in fact there are no professionals that do this kind of system for a living - or ever - it's a very specialized system you have chosen), it's all stuff you can answer on your own with a little bit of empirical testing.
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JAG,
1) Sorry, but I don't see any ballot forms here 🙄.
2)You certainly do like to repeat yourself, each post is like Deja Vu all over again.
3) I never suggested mains be placed to the side of multiple subs, I suggested some of the problems with that approach.
If using only one sub, placing L/R in a soffit/barn door makes sense in some aspects, though also is problematic in others.
Cheers,
Art
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Really? Remember this?
... I would "vote" for dual subs ...
That's your own words from post 727, just before 11 am this morning. You cast your vote in those exact words, as if it wasn't clear enough from your previous cryptic posts, at least I was able to decipher them.
Sometimes this is required when people refuse to listen or acknowledge what's been said. I could say the same of you, how many times have you said "financial gain", "pay for design advice" or similar phrases in this discussion? Would you like me to go back and count? I could but I'm guessing well over 2 dozen, so don't talk to me about repeating myself. (You used the term "financial gain" in post 727 just a few hours ago, to continue the post 727 theme.)
Yes you absolutely did suggest the mains should be to the sides of the sub long ago. You also much more recently (just before 11 am this morning) said very clearly in post 727 ... I would "vote" for dual subs located directly beneath or !!!SURROUNDING!!! the stereo mains ... which very clearly indicates that you don't think the problems with putting the mains to the outside edges of the sub (which is EXACTLY what is proposed for a single central sub setup) is a non starter despite your comments about the soundstage wandering with the c - c distance of the mains placed to the side of the sub - in both the single and dual sub setup the mains to the side of the sub are exactly the same c - c distance from the sub. And you wonder why I repeat myself when your own statements MADE ON THE SAME DAY directly contradict each other.
While you seem to insist on playing semantic games and saying you didn't say things you clearly did say (I can find the exact quotes if you like for EVERYTHING you said, just like I just did for your dual sub vote BECAUSE I'M PAYING ATTENTION TO EVERYTHING EVERYONE SAYS WHILE IT APPEARS YOU ARE NOT EVEN PAYING ATTENTION TO THE THINGS YOU SAID JUST A FEW HOURS AGO), it would be more constructive to talk about technical issues in clear concise language with a minimal amount of anger, condescension, and mystery.
You are being very passive aggressive and cryptic with your responses in order to maintain some mystery as an incentive to gain financially from this project. Fortunately I have persuaded you to clarify your recommendations so we all know exactly what you are recommending so OP won't have to pay you several hours wages and a free trip to Seattle to figure out that you vote for dual subs and don't have any particular problem with putting the mains at the side of the sub(s), as you own quote from this morning clearly illustrates.
Weltersys, can you see why we aren't getting along here? In response to your 3 points in this quote, I used your own words from post 727 to directly counter these 3 points. It's like I don't even have to contribute any original info anymore, just use your own quotes to show the problems in your own statements. And two of these points in this quoted post are emotionally driven passive aggressive garbage, only the third point is remotely technical in nature and it directly contradicts what you said a few hours ago. Come on, try a little harder, you can do better than this.
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ignorance knows no nationality (and using nationality in that context is bad form)
i think Entropy is gardening or shopping at the mall
i can't figure out why this is something that seems so personal to JAG that he can't let it rest nor do i see it as a deal breaker in the larger scheme of things.
i think Entropy is gardening or shopping at the mall
i can't figure out why this is something that seems so personal to JAG that he can't let it rest nor do i see it as a deal breaker in the larger scheme of things.
I wonder too. The endless self-aggrandizing bickering gets in the way of productive progress. No other thread has as much personal boasting from wan egos. But that criticism doesn't apply to just a guy since he appears to have no experience to boast about.
B.
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