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Hi Soho,

first of all many many thanks for your efforts! I've learned HR by your thread, so I must be thankful to you!

Excuse me if I don't write much correctly, but I'm from Italy, so it's not my mother language :innocent:

What I would like to know is (if it's allowed in HR) how can I simulate the use of more than one speaker in same box, placed one next to the other along the horn axis. I am designing some boxes using the Quasi-6th Order Series-Tuned BP simulation and I want to try to use two speakers instead of one. I guessed that if I build a twice big box, like two of them symmetrically opposed (clamshell style) I can just tell to HR that I am using two woofers, and double volumes and areas, but I think that using two woofers placed at different pathlenght from S1 should be a different movie...

Can you (or anybody else who have a clear idea about it) tell me something?

Thanks in advance, and keep it going like that!

Roberto
 

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Many thanks for reply.

BUT

my wondering is about this: if I have more woofers inside the box, and they are vertically lined like in this picture, I can, for sure, tell to HR the number of speakers (series + parallel eventually grouped), and giving the correct volumes and areas I then get the total response. This is "easy" to understand since we can split the box in smaller single-woofer ones, and consider the complete subwoofer box as a stack of them.
Every single box can be considered a "quasi 6th order bandpass" and simulated with HR.

Look at the image and then go to next post, since I have less than 5 posts and cannot use image gallery :foottap:
 

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If I have a box like the one in this picture, the response of the two woofers MUST be different one to each other, since they are not equally far from the back of the box!

This is the reason for my first question: when I build a box like that, the two woofers close to the back of the box are probably interfering with the two close to the mouth, since they will have not phase coherence.
We know that distances play a big role in tuning and so in FR and phase response of the box (system).

Or am I wrong, and I'm self-making a lot of caos in my brain for nothing?
 

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I am already having troubles to design such boxes, since they must then used inside cars! So after all the HR simulation I'll be involved in real life measuring and tuning, so I want to be as much accurate as possible in first designs steps, and then find a way to include vehicle environment's effects into calculations.

Thanks a lot to everyone who will give his opinion!
 

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Thanks again, Mark!

The doubt was coming out from building a Transflex subwoofer, where putting two speakers in-line made the response smoother because of in-phase/not-in-phase adding of the second woofer to the first one.
Given that I can model a Transflex easily with HR in TH mode, I was thinking that probably there must be a way to "tell" to the software the distances between the two drivers, and let him calculate the sum of the two emissions at the mouth of the "horn".
 

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wave length calculator:

http://www.mcsquared.com/wavelength.htm

example 100 hz wavelength = 3,44 meters divide that by 4 to 1/4 you get 0,86 meters as long as your drivers are this close together or closer they act as one driver at this frequency and below.

Mark
I guess that as "distance between speakers" you mean between their axis, right?
 

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Let's say that we simulate the two (or whatever) speakers as one, and put this "big speaker" in the S3 position.
Then, yes, I realized that the sections and their distances are just to tell to the software how this "horn" is made, and let it calculate graphs based on flares dimensions.

Many thanks, your help was really appreciated!
 

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I guess you can easily simulate that box using the same method used to simulate a ported box, like written in post #6... Just put throat area a s S1 and mouth area as S2, and L12 as distance between the two.

I tried to simulate boxes like that for car audio use, and worked fine!
 
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