JBL room mode calculator

[JBL 4645]

Does anyone have a link to the JBL room mode calculator I seemed to have lost the link on my other pc and can’t remember the precise key word name I’ve done a search here and drawn a blank here.

[Zilch]

The gizmo?

http://www.jblpro.com/products/recording&broadcast/LSR6300/RMCUserGuide.pdf

http://www.jblpro.com/products/recording&broadcast/LSR6300/White%20Papers.pdf

[SteveW]

Courtesy of 'Knightfly' from another forum:


Harman has redone their site, and of course nothing works anymore http://johnlsayers.com/phpBB2/images/smiles/icon_sad.gif
http://www.harman.com/about_harman/technology_leadership.aspx (http://www.harman.com/about_harman/technology_leadership.aspx)
Then click on "White papers" -

This brings you to a page where you can either read their papers, or click on "Calculators" - you want "Calculators".

Then, click on "Read" - it will bring you to a page where you can download either of the two calculators offered, one of which is the mode calc.

Cheers...

[JBL 4645]

It looks like this! I just can’t remember where I downloaded the program from?

http://cgim.audiogon.com/i/vs/s/f/1127985098.jpg (http://cgim.audiogon.com/i/vs/s/f/1127985098.jpg)

[Valentin]

does some one know if there is a rome mode calculator with the positional calculations for speakers and litsener

[JBL 4645]

Well I was kinder hoping f someone remembers what the above one is and where the no nonsense link is as it was uploaded on my other pc which I no longer have.

[JSF13]

Well I was kinder hoping f someone remembers what the above one is and where the no nonsense link is as it was uploaded on my other pc which I no longer have.

Did a search on Dan Siefert and found this one if you can open it. Think it requires Excel

http://www.oneononetech.com/free_stuff.html

[JBL 4645]

Did a search on Dan Siefert and found this one if you can open it. Think it requires Excel

http://www.oneononetech.com/free_stuff.html

Yeah stuff that one mate I can’t open it :banghead: not as easy as the JBL version, no wonder they don’t want to share with the other children.:D

[JSF13]

Yeah stuff that one mate I can’t open it :banghead: not as easy as the JBL version, no wonder they don’t want to share with the other children.:D

Sorry mate.:( I did some more research. Looks like it is a Microsoft Excel requirement. Couple of references here.:)

http://www.google.ca/search?q=Dan+Siefert+room+mode+calculator&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

[Hoerninger]

Did a search on Dan Siefert and found this one if you can open it. Think it requires Excel Open Office will do, it is available for free on many platforms.
____________
Peter

[SteveW]

Hello again Valentin. Here's a link to a thread you may find interesting. It's a clever application using the JBL calculator for ballparking speaker/listener placement. I say 'ballparking' because some rooms don't measure up quite as predicted. Both frequency and location change from calculated to actual for a bunch of reasons. You could find the nulls/peaks in your room with a SPL meter and freq generator and adjust your plot accordingly...

Cheers

http://johnlsayers.com/phpBB2/viewtopic.php?t=2441

[JBL 4645]

Thanks mate for the above link.:) I just left a message over there see if this works out in getting a direct link to the software program. I can’t understand why Harman would want to make it so difficult in finding a program software to help users solve and plot out the room where these room mode bugs are, oh well its not a perfect world is it.

[Valentin]

JBl 4645

here the link for calculator
http://www.harman.com/about_harman/technology_leadership.aspx

SteveW thanks por your post

[JBL 4645]

JBl 4645

here the link for calculator
http://www.harman.com/about_harman/technology_leadership.aspx

SteveW thanks por your post

Valentin

Bravo thanks mate now that is what I was looking for many thanks mate many thanks.:applaud:

[JBL 4645]

Okay I’ve inputted the size of the room and it’s done the calculations. So how do I deal with this issue with minimal fuss?

I highlighted the data which had the figures and the darn thing was presented horizontally instead of vertically.

[SteveW]

JBL 4645, here's a 'minimal fuss' path.

Study up on how to use that calculator here: http://www.harman.com/wp/pdf/LoudspeakersandRoomsPt3.pdf

Then go here and do the exersize on page 2: http://johnlsayers.com/phpBB2/viewtopic.php?t=2441

Cheers

[JBL 4645]

After a brief talk with bop in the pm about the (JBL room mode calculator), you see I’ve been re-thinking the room differences over again, for the 10th or so time. Last night I uploaded the (JBL room mode calculator) and measured out each room, then inputted the data.

So has you can see from the image the image on the left-hand-side is the small room where it is at present. The data on the right-hand-side is the larger room, note I placed a seat indicated in RED, bop was telling me something about the first order and second order which was too heavy for bass, something like it should be avoided.

Now where should I place the JBL sound system, before I start committing myself, to laying down an MDF flooring in the not too distant future.


http://i233.photobucket.com/albums/ee15/Evolution3417/LargeVSsmallroommoderesponceJBLseat.jpg

[boputnam]

...bop was telling me something about the first order and second order which was too heavy for bass, something like it should be avoided....

Glad you posted this, Ashley.

What I first said was I am not experienced in interpreting these. :o: Then, I went on to speculate the following:

RH image (L = 15-ft):
- common 75Hz nodes shared in both 1st (H) and 2nd (L) orders. That can't be good and suggests to me LF loading of the room. I especially don't like they are shared with the 1st and 2nd orders - the two strongest.
- nearly common ~110Hz notes shared in both 2nd (109Hz, W) and 3rd (113Hz, L) orders. ibid - loading of 110Hz will be difficult to tame.

Where you have positioned the chair will be least impacted, but still the room is going to be pretty excited by 75 and ~110Hz - not ideal to me.

LH image (L = 11-ft 10-in) is marginally better?
- common ~145Hz node shared in both 2nd and 3rd order. This overall looks the easier of the two options to sort out. However, you would not want the chair positioned at ~9-ft out - that would be sorta resonance heaven for the ~145Hz node...
- the dual/broad nodes at 95Hz (L) and 105Hz (W) both in the 2nd order could be real trouble. This could prove real difficult to tame, requiring a pretty massive notch at 100Hz.

Caveat: I do not know what the inputs are, and/or whether changing crossover points, cabinet positioning or polarity could mollify some of these nodes. I am only trying to interpret the given result outputs, with no view toward changing the inputs.

:dont-know

[JBL 4645]

bop

Difficult to tame, you say, what about a DIY made bass trap placed in a few back corners would this tackled the issue at 110Hz?

[boputnam]

That may work. Can you input that bass trap into the models?

[JBL 4645]

That may work. Can you input that bass trap into the models?

bop

LOL :D I really wouldn’t know where to start, unless one of the other guys has general idea on how to input that data?

[JBL 4645]

Now since I’m going to have at least 8feet 6” or 102” if that helps, on the left-hand-side-wall extended. So within the 8feet 6” or 102” area the room will in fact narrow or be decreased in width to around 8 feet 11” or 107”.

The back part with its slight open space will have a width of 106” or 10 feet 6” from the right-hand-side-wall to the left-hand-side where the door is.

I think a different computer model is in order here, because this assumes the room has straight walls…Well almost.


http://i233.photobucket.com/albums/ee15/Evolution3417/JBLroommodecalculator.jpg

[boputnam]

Does anyone have a link to the JBL room mode calculator...?Yea, I found it.

JBL interchangably calls it WAVES or Room Mode Calculator (http://www.harman.com/xls/Room%20Mode%20Calculator.xls). It's Excel based.

[JBL 4645]

bop

Yes that’s true Excel, but how to figure it out in to the simplest terms I can’t seem to understand and yet looks so simple.

[boputnam]

Here's my Google search (http://www.google.com/search?q=room+mode+calculator&rls=com.microsoft:en-us:IE-SearchBox&ie=UTF-8&oe=UTF-8&sourceid=ie7&rlz=1I7GGLR) on Room Mode Calculator. Surely there is reference stuff there to help.

[grumpy]

... as has been pointed to here before, this site has some tools that might help
with visualizing what's going on in regard to room modes:

http://www.hunecke.de/en/calculators/index.html

[boputnam]

Good one, Dave...

I should add the Acoustics of Small Rooms (http://www.acoustics.org/smallrooms.pdf) presentation here, too. It demystifies the presentation of modelling results.