Can someone recommend me a room mode calculator?

lovecow wrote:

I don't have the time for another pi$$ing match

Now, now, Jeff, this is not about pissing contests, it's about furthering the general body of knowledge. That you even refer to my post as a pissing contest says more about you than about me. :oops:

Information is deliberately being left out.

You bet, and deliberately is the key word. Every time I see Bob Golds (bless him for all his hard work) post a list of 100 modes from his calculator in response to a beginner question at AVS, I always wait for the recipient to ask what the hell he's supposed to do with all those numbers. But they never ask, I assume because they're intimidated or don't want to appear stupid. I'm not a fan of saying, "Let's agree to disagree," but in this case I think it's appropriate. I am not trying to force my opinion on anyone, and I can absolutely see why you and Eric and others feel my omitting non-axials is unacceptable. My mode calculator is only one of dozens that people can download for free. I am not in the least offended if someone chooses to use Eric's fabulous Excel calculator, or Bob Gold's fabulous Java calculator, or any other program out there. But I stand by my assertions that 1) axial modes matter more than non-axials, and 2) showing people 100+ modes, all a coupla Hz apart, does not really help them very much. Here's the key: I would never insult or belittle someone who differs with me on this, as I have been insulted and belittled. I'm a black belt computer programmer, and I could easily add non-axials to my program. I simply choose not to. :)

you cannot censor information because you believe it benefits the user.

Why not? It's not like I hide the fact that my ModeCalc is axials only! I even explain that in the ModeCalc web page description which is the same as the program's Help text.

non-savvy users could obtain results from your calculator and make serious room design errors.

But with Eric's calculator they'd be sure to nail it? :roll: Actually, and not to add to your work load, but I would love to see a hypothetical set of room dimensions that someone might choose that looks good in my calculator but is a "serious error" in actual practice.

Of course, from another perspective, if you don't place any importance on room modes then why even bother with a calculator :?:

I stand by that too. I really do. I'm not saying that modes don't matter! But they are not the be-all and end-all consideration when designing a room. If you make a home theater room 2 feet shorter to have better modes, but now there's no room for your mother-in-law's seat, I promise you will be sorry you made the room shorter. And Yes, I am absolutely serious!

the 3/6 dB difference is only relevant to modes of different types that occur at the same frequency. And it is theoretical.

I agree it is theoretical, and I'm not convinced non-axials are even that important in practice. As I think was made clear in the long RO thread, since modes predicted and measured can be so far off, how do we even know that a measured strong mode really is non-axial? Thanks Jeff. I forgot how much fun it is to argue with you! :twisted: --Ethan

gullfo wrote:

except in the case when a nearby frequency mode or combing filter effect causes the note to appear to become sharp or flat(ter). :?

LOL, good point, Glenn. I've been thinking about exactly that for the last few weeks, after I posted THIS idea for room mode selection. I kept thinking I should go back and point out the error in my own logic, and I gladly acknowledge that potential problem here now. --Ethan

Ethan Winer wrote:

...and I can absolutely see why you and Eric and others feel my omitting non-axials is unacceptable.

Which is all anyone can ask. :)

you cannot censor information because you believe it benefits the user.

Why not? It's not like I hide the fact that my ModeCalc is axials only! I even explain that in the ModeCalc web page description which is the same as the program's Help text.

non-savvy users could obtain results from your calculator and make serious room design errors.

But with Eric's calculator they'd be sure to nail it? :roll:

This is a philosophical difference. Since you place a relatively low importance on room modes, you (gently and openly) force that bias on users of your calculator. This doesn't set well with me...and it never will. Succeeding or failing when all the information is available is different than succeeding or failing when all the information is not available. It doesn't matter whether the lack of 2/3 of the mode types would only affect 1 in 2 or 1 in 2,000 or 1 in 2,000,000 users. That even 1 user could be affected is exactly the point. It also doesn't matter whether or not I can produce specific examples of cases where mistakes would result from adhering to results that are generated by your calculator. (I feel I can. ;) ) In the end, mistakes - even (IYO) rare ones - could happen. And that they could happen is (also) exactly the point. Yes, the user could make mistakes even when presented with all the information. But that's not an excuse to leave out information. In fact, that is (also also) the exact reason all the information should be provided. Of course, it is made clear to the user that your calculator leaves information out. But pointing out there is missing information is not the same as providing all the information, then filtering it and explaining why you feel it is necessary to do so. This is just how I feel about it. All the best,

I'm a black belt computer programmer, and I could easily add non-axials to my program. I simply choose not to.

I say "LET THEM HAVE IT". :D You could always explain your side of it. Your graph, to most, seems much easier to understand, (then most I have seen) then why not? Like I said you could always put your own copy with it to help the user understand what is what. Ever heard the term "have your cake and eat it too"? :lol: Glenn

Ethan Winer wrote:

Actually, and not to add to your work load, but I would love to see a hypothetical set of room dimensions that someone might choose that looks good in my calculator but is a "serious error" in actual practice.

(Man, I just can't seem to let go of this today...) I don't think the reason I'm arguing is because something could "look good" on your calculator, but still result in serious error when using another calculator. That could happen, but I have cited works that support your argument of addressing room design from purely an axial mode perspective. I still don't think it's correct, but I can grant some leeway there nonetheless. I think my main point is that mode calculators are a tool used by many to identify the nature of problems that are already being perceived. Gross errors could result from using your calculator to design a fix to an existing problem. To that end, here is a specific example of how things could go wrong:

Bubba's room is 14'x12'x9'. Bubba is mostly pleased with how it sounds, even without any major acoustical treatments. The only problem is that whenever the bass player hits that B note, it completely vanishes. Bubba gets on the web and finds his way to Ethan Winer's website. For the most part, people seem to trust this guy's opinions when it comes to treating small room problems, so Bubba's going to use Ethan's room mode calculator and see if he can't figure this out. Lo and behold, Ethan's program tells Bubba that, sure enough, there's an axial mode {0,0,1} right at 63 Hz, which is darn near that bass player's B note. Bubba presents his problem on {insert favorite Internet forum} as, "How do I treat a 63 Hz axial mode?" and finds out he can design panel "traps" that specifically address this floor-ceiling mode. And, further, if he puts them smack in the middle of the ceiling - where he has plenty of room - it should make a significant difference. Now, Bubba is a skilled carpenter and designs his panel traps to within 1/16" tolerances using all the right formulas. Bubba rigidly fixes his (very pretty) "traps" to the ceiling and fires up his mix. Well, now Bubba's plumb confused. He has done everything right and he can hear a slight difference, but, for the most part, the B note is still doing its vanishing act right at the start of the chorus. Bubba goes back to {forum} and presents his grief. Those who helped guide Bubba to panel "traps" obtain more information and only now learn Bubba's room dimensions. Plugging them into a non-Ethan Winer calculator, they discover the {1,1,0} tangential mode at 62 Hz. Bubba's now getting plain frustrated. Sure, corner traps could work just fine and he could build them. The trouble is, he blew his budget (and time) on the ceiling "traps." And he only has 1/2 of one corner in the room available that is not obstructed by doors, furniture, or gear. And he doesn't even trust that putting corner "traps" in could help since he barely noticed any difference when he put the (pretty, expensive, labor-intensive) "traps" on the ceiling. Before you argue that Bubba was hosed from the start because he couldn't have put anything in the corners anyway... And before you argue that Bubba will eventually realize some benefit from the ceiling "traps" if he can ever get to the corners... Consider that Bubba now thinks Ethan Winer is a soulless ne'er-do-well for plugging a mode calculator that didn't tell him everything he needed to know. Consider that Bubba put 3 days of work (when he could have been mixing) into "traps" that he now feels were far from worth the effort. Consider that had Bubba known that he needed to address both problems from the beginning, he may have approached things differently. Consider that had Ethan Winer been able to tell him from the beginning to address both problems, then Ethan may have come out being the hero instead of the villain. And so on...

Lots of things to consider, I guess. :roll:

lovecow wrote:

This doesn't set well with me...and it never will.

I can live with that. But you will never see me criticize someone else's calculator for being too complicated to use, and too verbose, because it shows non-axials. That's the main point I was trying to get across. Hell, I wouldn't even mind if you or Eric chimed in every time I posted a link to my ModeCalc to say, "Be aware that Ethan's calculator shows only axial modes, and many of us believe the non-axials are important too." What I object to is all the name-calling and insults, and accusations of incompetence. I hope you can see my point.

That even 1 user could be affected is exactly the point.

Ah, so you're the guy who petitioned the US government to force every automatic garage door opener to have those damn sensors that constantly trip when wet leaves get stuck under my garage door. Thanks a lot, pal! All in the name of saving one kid from winning a well-deserved Darwin Award. :)

It also doesn't matter whether or not I can produce specific examples of cases where mistakes would result from adhering to results that are generated by your calculator.

Actually, it does matter. I see you replied later with such an example, but that will have to wait until tomorrow for me to look at. It's almost 8:00 pm and I'm hungry NOW! --Ethan

myfipie wrote:

I say "LET THEM HAVE IT" ... Your graph, to most, seems much easier to understand

Yes, and the reason it's easy to understand is because it's simple and uncluttered! As soon as I shoehorn in all that extra info which I do not agree is as important as Jeff and Eric say, it will be as convoluted as all the others. BTW, I'm not the only person who believes axial modes are the main problem in most rooms. I read an article on John Storyk's site once by his head acoustician that basically said axials are the only modes that matter. If I can find that article again I'll post a link to it. I am perfectly happy for people to use Eric's Excel spreadsheet if they want the extra info. How about this offer: I'll add a link right from the RealTraps ModeCalc page to Eric's version, and I'll add what I wrote above that some/many/most acousticians believe non-axials are important and must be considered. All I ask is one very basic thing: Wherever Eric's spreadsheet resides that I link to must not contain defamatory statements about me or RealTraps. Which rules out the spreadsheet's current home. Deal? --Ethan

Ethan Winer wrote:

That even 1 user could be affected is exactly the point.

Ah, so you're the guy who petitioned the US government to force every automatic garage door opener to have those damn sensors that constantly trip when wet leaves get stuck under my garage door. Thanks a lot, pal! All in the name of saving one kid from winning a well-deserved Darwin Award. :)

The kid who slips (which kids are wont to do) on the wet leaves that his old man didn't clean up, bangs his head, and is knocked out under the descending garage door would hardly be deserving of a Darwin Award.

I see you replied later with such an example, ...

I gave this some more thought, specifically regarding room design. You linked to an RO thread from 2005 earlier in this thread. In that thread, I gave you some information from Gilford's paper regarding his recommendations for a maximum axial mode spacing of 20 Hz. From this page, it would appear that something like that has not been incorporated into your calculator. The reason I mention it is mainly because: (a) It could be really easy to include, (b) It could help make your ModeCalc at least moderately more useful (IMO) for room design, and (c) It could lend more weight to your argument. Gilford was no hack. Please understand that I'm not demanding (or even requesting) any sort of changes on your part - just curious about your thoughts on this... :)

Jeff, I do agree with you that it might be best for Ethan to "cover his butt" and redo his program, BUT I do find your story a little unlikely to happen in the "REAL" world. If Bubba would have read Ethan's site, he would have also read that tuned bass traps in a small room, like his, is NOT the best way to start. Also it is not Ethan's fault that some guy from (insert forum name here) told him to build them in the first place. :D Glenn

lovecow wrote:

In that thread, I gave you some information from Gilford's paper regarding his recommendations for a maximum axial mode spacing of 20 Hz.

Thanks for the link - that was a great post you made there! My ModeCalc program does not highlight too-wide modes, but it does highlight too-near modes. The ModeCalc web page states:

When viewing the results look for an even spacing of the modes regardless of their color (good), and also look for multiple modes that occur at or near the same frequencies (bad). Also compare the ratios of the dimensions you entered with the recommended ratios, and compare your room's volume with the recommended minimum of approximately 2500 cubic feet or 70 cubic meters.

I don't know how much clearer I can say it than that! I also looked at the "clarity and quality" of the Help in a number of other mode calculator programs on the web. Other than Eric's, which is very extensive but too much to expect beginners to read and understand, none I came across had explanations I consider useful. It seems to me that telling people what they're looking for is at least as valuable as the program's output. --Ethan

lovecow wrote:

Consider that Bubba now thinks Ethan Winer is a soulless ne'er-do-well for plugging a mode calculator that didn't tell him everything he needed to know.

LOL! I had to read that three times to figure out what you're trying to say. If I understand your point, it's that poor Bubba put the wrong kind of trap in the wrong place all because of my failings as a human being. Does that about sum it up? :P Seriously, if Bubba put a tuned trap on his ceiling, it was not based on any advice I would have given! --Ethan

Glenn: Unlikely...but not impossible. If I learned anything in my 8+ years at Auralex, one thing was to never under- or overestimate the things your customers are capable of accomplishing on their own. Ethan: :) Similarly, getting into the mind of your customer is tantamount. You and Glenn could both argue the unlikeliness and implausibility of Bubba's plight. But you also have to ask yourselves if it's a chance you're willing to take. As far as other calculators are concerned, you might consider that a majority of them are either offered for a fee, in which case there is an implied requirement of not omitting any information, or they are offered by individuals (Eric, John, Bob, me, etc.) as opposed to owners of successful acoustical treatment manufacturing companies. ;) You could replace all instances of "panel 'traps'" in the Bubba example with "MiniTraps" and have an even worse customer satisfaction problem on your hands...regardless of where or from whom Bubba got his initial help. Of course, with any venture, there is risk. And you might surmise that this is not a huge one, by any stretch. Which is fine. As I said, this is just how I feel about it. ;)

Glenn: Unlikely...but not impossible. If I learned anything in my 8+ years at Auralex, one thing was to never under- or overestimate the things your customers are capable of accomplishing on their own.

If I ever make it to KS city we must sit down and swap some stories. I got some great ones that still make me laugh. Glenn

lovecow wrote:

You could replace all instances of "panel 'traps'" in the Bubba example with "MiniTraps" and have an even worse customer satisfaction problem on your hands

As they used to say on LA Law, I'll take that under advisement. I can tell you that RealTraps has treated thousands of rooms by now, and I can count the number of dissatisfied customers on both hands. And none of them were dissatisfied because my ModeCalc program threw them a curve. :) Thanks Jeff, you're one of the coolest guys I know. And I really mean that. --Ethan

Here's another thought on a slow afternoon before a major US holiday. I intend this in the most conciliatory manner possible:

Ethan Winer wrote:

lovecow wrote:

I don't have the time for another pi$$ing match

Now, now, Jeff, this is not about pissing contests, it's about furthering the general body of knowledge.

You recently brought up the long-standing "pissing contest" of whether modes are the same as standing waves. Your stated intent was to try to resolve this for purely scientific reasons. My intent here is exactly the same - to settle an important matter once and for all. Some day I'd like to duplicate the experiment that you (I think it was you) once said a noted acoustician did, where a tiny "room" with very rigid walls was built and measured for actual versus predicted modes. --Ethan