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Hello Mark, Thanks a lot for your reply. Yes, I think that by placing the drivers next to each other, this could lead to phase problems while increasing the SPL. by setting them 100 cm apart, the objective it to overlay the standing waves with a 1/4 wave difference constructively. When one is at zero-crossing, the other is at max amplitude. But only at one frequency ...
I am building a test enclosure and have the drivers already.
First, I want to use the horn sound and the free to air part. Second, the first driver should be as close to the throat as possible. With a throat area of 450 cm2 and a mouth area of 2400 cm2, volume 500 liters there are few ripples, usable up to 400 Hz and phase response looks good, smooth up to 400 Hz, -45 to -90. Can post the hornresp results, can't do it on this virtual machine. Will configure the 2 drivers in various ways and measure it ... best regards Marc
 

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Marc, you seem very enthusiastic in your pursuit of good sound.

Here are a few things that are not part of what you are trying to do.

Phase describes space and time. Two components. Where something is in space relative to time of the measurement period.

In a loudspeaker the only way this can really cause you problems is if you have two drivers that are wired in such a manner that one driver is moving in one direction and the other is moving in the opposite direction. This not out of phase but actually anti-phase to each other. This will create a null at some frequencies but not all, and is really determined by more things than I care to tackle right now.

Your desire to create an infill is better pursued by cabinet construction lengths than another driver. The second driver idea, while it has it's merits, only has those merits at and above the frequency where the distance between driver "A" and driver "B". Look up a frequency to wavelength of sound calculator, and you will see that there are longer wavelengths for lower frequencies, and shorter wavelengths as you go up in frequency.

Again, if you do your box effectively you will mitigate most of your problems. Make a bend near the 1/2 wavelength of the frequency where you have a problem. But take note of this simple fact. A tapped horn is not a wide band device. two to two and a half octaves in frequency are all that a tapped horn, or tappered pipe type loudspeaker are able to do much with. If you try yo do more you will have a suck out in the middle that you will not be able to fill in.

Octave: 16 to 32 hertz in an octave. 32 to 64 hertz next octave, I think you figured out the next octave is 64 to 128 hertz. These are nice round numbers, actual note for note frequencies are slightly different.

Going up to 500 hertz with a tapped horn will cut you off around 100 hertz on the low end dropping two octaves.

If you are happy with this, then fine! But I really wonder if you have a tapped horn, or a tappered pipe enclosure. I have seen only a handful of true tapped horns posted on the internet. If you want some guidance look up jbell on diyaudio. He definitely knows what he is doing.

And he does a boat load of well designed PA cabinets that have serious usefulness.
 

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Hello Mark, Thank You again ! The 15" will be used up to 150 Hz. I am not shure if it is better to mount the driver in a TH or OD configuration. I want to build a double horn in the same enclosure with 8" drivers + compression driver on the front side. 3-way system with active XO. Your advice regarding phase has calmed my fears. Best regards Marc
 

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Hello Mark, I have no idea what a W bin is. Found a thread at http://forum.speakerplans.com/w-bin_topic28082.html but no details. If you have plans for such a bass-bin, kindly send them by PM. I have planned several TH, but I find that it takes up a lot of space, plus needs additional enclosures for MF-HF. This is why I want to combine a horn for 1-2 15" drivers and smaller conical horn for 2 8" drivers with the same final horn path. Will be big, but just one enclosure. If I make a narrower front baffle ( 25 cm vs 45 cm backside) the carpentry becomes a challenge. I want to have a sufficient horn-lengh and mouth area, am not going to cheat on this. Have a nice day in Canada ! Marc
 

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Re: Offset Driver Horns

Thanks Soho54
About OD horns driver access aperture to horn: I see your very sensible illustration incl S1, S2, S3, S4. Thats all fine, but: Where and how do you input the area of the drivers apertures input to the horn ? Is that allways equal to S2 ?
 

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I have never designed a speaker...so this is my first time trying to figure this out, and I want to design a 2 way Synergy horn. I have seen several designs, but i don't know what will happen if i use different drivers, and a different size horn.

I have a EV DH1A compression driver, and I was planning on using EV EVM 15L woofers. The plan I have seen that I like is http://www.diyaudio.com/forums/multi-way/244508-monster-massive-3.html.

Looking at the instructions at the beginning of the thread after downloading the latest version of Hornresponse...some of the fields are not the same. It would be appreciated if someone could help me fill this in so I can try different angles of horn, and lengths to see what will work best for me.

tia,
Ron
 

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This is an old topic with a lot of information. Can someone tell me if it is possible the calc. A mass loaded transmission line speaker in hornresp and if so how i'm able to do that?
I thought perhaps using the closed cabinet with port and stretch it out but... That will be to easy.

2nd question
If using closed box you can enter depth and volume. How can hornresp calculate width and height and is it possible to customize these values?
 
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