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Multi-Way Conventional loudspeakers with crossovers

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Old 22nd December 2012, 12:10 PM   #541
hajj is offline hajj  Lebanon
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Quote:
Originally Posted by CLS View Post
I've tried a similar one, with 2 problems:

1. the deep slot forms a strong 1/4 W.L. resonance, deep notch filter is needed if you play it up to midbass.

2. the cone (and air load) moving up and down, causing strong vibration to the whole base, efforts on isolating that from floor and other part of the speaker would be needed.

I dropped that eventually.
I think the reason to go for a 15 inch driver rather than an 18 inch one is specifically to minimize the 1/4 WL resonance's effect on overall response, since the 1/4 WL resonance is dictated by the depth of the cavity which in turn depends on the driver's diameter.
In the case of a 15 vs 18 inch driver this would give a resonant freq of 215 hz vs 172 hz (when total slot depth is taken at 40 cm for the 15 inch and 50 cm for the 18 inch driver)
This 38 hz difference plays a big role when trying to match woofer to FR driver, especially at the 180hz crossover frequency chosen by NP.

Hope I'm making sense

Nick
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Old 22nd December 2012, 12:32 PM   #542
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Quote:
Originally Posted by markus76 View Post
Qts should be about 0.5. With the right parameter set one probably can get away with a simple low pass filter. Let's wait and see how the SLS-12 Ripole turns out.
Here's the frequency response at the front chamber (24dB lowpass @ 150Hz, no EQ):

Click the image to open in full size.

That's what the Ripole looks like:

Click the image to open in full size.
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Old 27th January 2013, 09:57 PM   #543
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So, Mr. Pass, how do they sound?
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Old 28th January 2013, 05:14 AM   #544
jamikl is offline jamikl  Australia
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Sometime ago there was a patent for an old speaker shown in one of the forums. I did download it at the time but it is in an older computer which I don't have access to. Part of the design was a circular disc, about the same are as the speaker spaced out from the cone and leaving a gap all round. If this was done on an OB and spaced out so that the area between the disc and the baffle was 30 - 40% of the cone area, would this work? If it would it would have the advantage that the disc could be made out of a nice hardwood and turned like
a shallow bowl shape on the outside and nicely stained good looks and good sound maybe. I realise that it would not have to be turned for bass frequencies to flow round it but it could look good!!!

l
)
l The bowl would be flat where it faces the speaker. Speaker on left of baffle. Bowl shape would really be same size as speaker opening and the gap would be annular.
jamikl
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Old 29th January 2013, 06:25 PM   #545
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Default InDiBA 16.2 a different Slot Loaded OB Project

Quote:
Originally Posted by pengesluk View Post
Work in progress...
Nearly at the same time I presented my version of SLOB with high WAF in a small cabinet.
I'm totally astonished to see this thread working with same principle, collecting chassis area by arrays of chassis in a slot.

I think we are invented to combine all our KnowHow to go ahaed.

Some more words.
My InDiBA 16.2 started as a low cost event but went to a concept of scalable SLOB.
What's new ?
InDiBA is a synonym for Integrated.Dipol.Bass.Array and it means something similar to a W-Frame but with an array of chassis in a special arrangement.

First I want to have a small box/baffle, so I need to compress the chassis as close as possible and I did.

Click the image to open in full size.

16 x 5" Sub plus COAx-Tangband >> 18,5 x 94 x 34 cm³

Later on I did some homework in Germany: Sorry, search for:
DE202012008642U1

It's only to be shure no one will earn money with my ideas.

wr
Wolfgang
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Old 29th January 2013, 06:47 PM   #546
Juhazi is online now Juhazi  Finland
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Wolffgang - that's a wonderful and ingenious design!

Google did't give me any results for DE...

Do you have any measurements, perhaps horizontal dispersion...

How to model that bass part in Hornresp?

Oh, here is the link http://www.diy-hifi-forum.eu/forum/s...ead.php?t=5231
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Last edited by Juhazi; 29th January 2013 at 06:50 PM.
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Old 30th January 2013, 11:51 AM   #547
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Here are some more details: IGDH http://www.igdh.eu/wp-content/upload...DiBA-16.21.pdf


Simualtion is a good idea, I'm currently looking for a dipol simulation.

Wolfgang
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Old 24th February 2013, 03:55 AM   #548
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I wish I had room for an OB, but I just can't have my speaks a meter into the room, while I was still fantasizing about it I found this site that has surplus Infinity, Cerwin Vega and Sony speakers all with high Qts. from 6"-10". The 6" CV are 6.00$, the 10" 150 watt Infinity 12.50$.... Ohhhhh, maybe I'll build them on casters and roll 'em out just when I'm listening, I just LOVE this design!
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Old 24th February 2013, 03:57 AM   #549
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I think I forgot to put the link, and since I'm still a probationary member I can't see it, If I forgot it's
Speaker Stuff
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Old 1st September 2013, 04:43 PM   #550
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I finally finished one of the bass unit for my Lowther horns(PM7A). I'm using the horn full range to about 150-160hz, and using mindsp for Xover and EQ for the bass unit. I'm not sure if the JBL 2226J is a good match for the design with a Qts of .31 and Fs of 40hz. But I have 4 lying around , and they are efficient with good power handling capabilities. So far with preliminary test and listening with only one unit ... They sound very natural and is usable to about 35hz and matches my horns well. I need to build the second one and start tweaking
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