Accidental MLTL Technique

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Indeed. My nanoTowers cost me about 30 bucks in wood. If they had failed, I'd still have the drivers for another project, and the time I had "lost" is a non-issue; I consider this a hobby, after all. The time spent doing it is half the point, maybe more. 30 bucks is cheap entertainment, IMO. I spend 3x that on a tank of gas.
 
Bill Poster,
Actually a BR is close, you are right about a little more volume as that will usually help bass extension. I play around in WinISD by adding a little volume and then convert the volume to a MLTL based on pipe length constraints and baffle width. I have gone with a smaller volume than calculated by the (and that also produced a pretty nice sounding result - I kept volume small to keep the wall mount speaker as low profile as possible.
Good luck, and thanks for the feedback.
X
Thank you,
so its somewhere between a BR and TL, volume wise
The new Jordan driver i think is just under 12litre optimal, so I was looking at doing a 14 litre tapered MLTL.
another question is with stuffing and SPL gains over a BR, I'll line the whole cab with a thin absorbent foam and lightly stuff half the line, so wondering if there wd still be any gains, hopefully the last half unstuffed and the taper will help
 
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Bill Poster,
When you start doing tapers, the AMLTL technique probably is not going to give you as good a result as a straight TL. At least that is what I noticed when I tried to do the Met. If you have HornResp, try using that for a tapered line. The new Jordan driver is a high end driver is certainly something if you spend that kind of money on, you may want to go with a proven design or a sim. Although, IMO, the sims I have seen of Jordan's 'proven' VTL don't look as pretty as my AMLTL's. I can give the new Jordan a go at it with my AMLTL method and let's see what comes out.
X
 
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AMLTL for Jordan Eikona

Here is what I came up with:
16 liter vol with WinISD BR tuning at 44 Hz.
Accidental MLTL design gives based on assumed 40 in pipe and 6 in baffle width.

L=40 in
Width = 6.0 in
Depth = 4.0 in
Vent dia = 2.0 in (round)
Vent Length = 6.1 in (downward firing)
Zdriver= place at 13 in from top or near top ~5 in for good height close to ear.
Stuffing in top 26 in of line.
 
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Gafhenderrson,
You are absolutely right about not wasting time or valuable resources on a bad design given how many good vetted ones exist. I would not do this with wood and expensive materials - hence the foam core speakers are excellent for this. If it's no good I have lost a couple of hours and maybe $3 worth of foam core. Thick high quality cardboard also works to try out new designs too.
I beg you pardon ..:eek:
No, it doesn't work like this: you need to ...
Make only the cone to move, and nothing else; hence the need for a very stiff material to do the job of separating the front wave from the back wave generated by the speaker. Every little deviation from these two 'laws' brings
tremendous changements in the perceived sound.
But...
Also a cabinet with ultra-stiff construction and a ultra-tighted speaker to the baffle has the ...hole on which the speaker is attached, and the membrane
in fono-transparent for the lower frequencies, so no real deal.
BY MAKING A CABINET WITH NON OPTIMAL MATERIAL AND THICKNESS
:shhh: Sorry!
You introduce more variables that just shouldn't be there.
 
Hi all,
Xrk said : Vent Length = 6.1 in (downward firing)
How did you design "downward firing" in Winisd ?
For curiosity what is the price of this driver in euros ?
Thank's.
Y try quickly a design with Mathcad, I found Vb 26 liters and 102 cm hight.
Rport 3 cm and Lport 18 cm locate at rear, but takes into account the walls. Without walls effect I found 13 cm.
Phil.
 
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Hi all,
Xrk said : Vent Length = 6.1 in (downward firing)
How did you design "downward firing" in Winisd ?
For curiosity what is the price of this driver in euros ?
Thank's.
Y try quickly a design with Mathcad, I found Vb 26 liters and 102 cm hight.
Rport 3 cm and Lport 18 cm locate at rear, but takes into account the walls. Without walls effect I found 13 cm.
Phil.

How do you fit 18 cm port in this cabinet? With 6 in wide baffle depth is 16.7 cm only.

Downward firing was purely consequence of needing to fit 6.1 in long tube into cabinet, I suppose it could have been made backwards firing if I had a tube sticking out instead of instead of flush. What does design look like with my numbers?

I have no idea what this driver costs. I am guessing it is about $180 based on J92x price.
 
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I beg you pardon ..:eek:
No, it doesn't work like this: you need to ...
Make only the cone to move, and nothing else; hence the need for a very stiff material to do the job of separating the front wave from the back wave generated by the speaker. Every little deviation from these two 'laws' brings
tremendous changements in the perceived sound.
But...
Also a cabinet with ultra-stiff construction and a ultra-tighted speaker to the baffle has the ...hole on which the speaker is attached, and the membrane
in fono-transparent for the lower frequencies, so no real deal.
BY MAKING A CABINET WITH NON OPTIMAL MATERIAL AND THICKNESS
:shhh: Sorry!
You introduce more variables that just shouldn't be there.

Pico,
Sure, the cabinet vibrates a little more than stiff wood, but the majority of the sound comes from the driver's direct radiation and the vent output. The purpose of the baffle is to separate the pressure from front and back waves and I contend that foam core does that just fine, and so would many of the folks who follow the foam core and cornu thread and have built speakers with these materials. Especially, for test or trial speakers to check out performance before committing to wood builds, it serves it's purpose well. Have you even built a speaker using foam core to make your statement that there are "tremendous changements" in perceived sound?
X
 
Perhaps the nice designs that were posted had dimensions that were too close to the AMLTL and he had second thoughts about sharing? Oh well...

Do you fancy yourself that much? Ye gods. No, it's that sort of comment / little assumption that made me take the posts down. You will find them on the main Eikona thread; they have been up for some time. As you will see, their dimensions are marginally less than bugger all like the box above.
 
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Scottmoose,
My original comment was a compliment to you saying the design was nice and would you mind sharing, after which you took them down without explanation. It would have been good enough to point to Eikona thread.

Yes, I have always fancied myself as an 'accidental' designer of speakers ;) Look, not sure why all the negativity here. We all know that a real model will be better - no doubt about that, and no doubt that your designs using sims work well. As I have said before this thread is an observation and I welcome feedback with sims showing if it works or doesn't work.
 
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How do you fit 18 cm port in this cabinet?
with a bend, or with port at bottom (downward firing)..
I post later my results.
Phil.

A bend! Good idea, forgot about that option. The nice thing with the MJK sim, as you are showing is that you can see the effect of rear, front, or downward firing port. Great advantage.
 
Scottmoose,
My original comment was a compliment to you saying the design was nice and would you mind sharing, after which you took them down without explanation. It would have been good enough to point to Eikona thread.

Yes, I have always fancied myself as an 'accidental' designer of speakers ;) Look, not sure why all the negativity here. We all know that a real model will be better - no doubt about that, and no doubt that your designs using sims work well. As I have said before this thread is an observation and I welcome feedback with sims showing if it works or doesn't work.

I do appreciate the compliment. FWIW, just to clear up some apparent misunderstandings in the above, I took those posts down less than five minutes after they went up; you presumably posted at the same time I was deleting them. It was only this morning that I saw a bunch of others had appeared. Living in the UK, there are certain differences in time zones. For the other, not that it matters, those boxes were not done by itterative simulations.
 
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Have you even built a speaker using foam core to make your statement that there are "tremendous changements" in perceived sound?
I used it for having equal volume in a folded and tapered TL,to be precise for the bends (gomits). then I covered all the inside with a wool carpet.
Now that you remind me...the enclosure is made out of cardboard :cool:

Tremendous changements, uh?
Once you diverge from what's inside the disc...
properly: an infinitesimally little changement produces an infinite grade of dissociation from what's inside the disc.
What's inside the disc is axiomatically unknown