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Old 30th April 2013, 08:56 PM   #1
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Default tqwtl predictions

Hi all,

Im looking to evaluate a transmission line enclosure vs ported for an AE td10m or td12m.
Response needs to be down to 60hz or lower (crossed over to a sub) and up to 600hz or so to a compression driver mounted on a JMLC 350Hz horn that I have already.

M J Kings site is informative (and very confusingly laid out!) but I cant see how to graphically compare the outcome of an alignment to a ported design.

The closest I have is this thread where the guy built a TL for a pair of td10m drivers, but mine would be a single driver.

The other issue is that I have is that I want to put this in a cabinet that is narrower than the driver itself (8 inch outside width, 7 inch internal). To do this, Im going to put the driver in a sonotube and the tube will intersect a standard floorstanding cabinet (just think of a standard floorstanding speaker - the 6inch bass driver 'hifi' type, but with a 10 inch driver shoved in the front with the edges extending past the baffle width.

Will a TL work if the driver is wider than the TL tube?

Would anyone like to suggest a layout or measurements for this with an area of 7inch (W) x 110-115cm (h) x 25-30cm (depth)? driver mounted at the top of the baffle.

Any opinions/musings welcome.
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Old 1st May 2013, 03:26 AM   #2
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Join Date: Feb 2006
Location: Cascais
The AE TD10M is a good candidate for BR and horn.
The AE TD12M is a good candidate for BR.
The 10" doesn't go that low. The 12" is a good candidate. I'm not good at designing TL's and can only look at their final designs and simulations. Other members do and I can help you in any other case.
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Old 4th May 2013, 05:41 PM   #3
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Join Date: Jul 2008
Ive bought a pair of td10m's and am in the process of trying to make sense of MJKing's quarterwave mathCAD worksheet.

Member OPC modeled a pair of TD10m drivers in a tapered TL here-

10" MTM with NeoPro5i Ribbon - Build Thread

As he says in post 51, he just modeled a single driver and doubled the area at each end of the pipe to correct for a pair of drivers.

I would like to deliberately target a peak in the output at approx 60-80hz in order to reduce the excursion the driver needs to make at a given spl- thereby reducing distortion as these will be crossed over at 60-70hz. This will be tamed with digital eq.

Now, If I have read correctly- the TL tube length is more or less set to a quarter of the Fs of the driver, but progressing from a tapered tube to a expanding tube pushes the resonance effects of the TL progressively higher giving you boosted spl at higher frequencies no? If this is correct, I will simply take opc's design, halve the tube area and flip it upside down!

Advice welcome.

PS- M J King's mathCAD worksheet asks for s0 and sl, but it doesn't state what the units are- inches or mm or cm - can anyone help?

Last edited by lbstyling; 4th May 2013 at 05:45 PM.
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Old 5th May 2013, 05:39 PM   #4
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Join Date: Jun 2007
Location: eastern PA
The dimensions can be in any of those units. Just label them (in, mm, cm, m) & MathCAD takes care of the rest!

Cheers, Jim
A day without music is like a day without food.
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