Side Table Sub

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Hey guys,

I am few steps further in my learning proces for designing a Tapered Quarter Wave Transmission Line.
In my first post I tried to design a very slim sub, but you guys teached me very well! So I scrapped that design.
Looking around my living room I found another spot. Told my wife to make her a nice side table. :D. A table along the couch with space for a plant and a drink.

Because of the depth of the couch I can me a nice deep box with room enough to fold a very long TL.

My goals:
- flat between 20 Hz and 80 Hz.
- tight budget: €200 driver, €100 amp, some wood+filling etc. Max. total €400.
- SPL 110 dB is more than enough. ! have kids and neighbors...

So far I found this:
SB Acoustics SB34SWNRX-S75-6. A 12" sub with a low Fs of 19 Hz and a nice xmax of 11 mm for only €170.
And I think I can feed it with an AIYIMA A3001. 300 Watts should be enough and it has a knob to cutoff at 80 Hz, so I don't need any crossover stuff. €70:up:

Playing around with Hornresp I discovered that a big offset combined with taper on both ends makes a very nice flat acoustical power from 20 Hz. With 140 Watts it reaches xmax at 114 dB.
Then the folding. The shape of my enclosure is different from most examples. I came up this curved TL. It is like a squared snail-shell. What do think of this TL. Would it work? It has 1400 mm from the closed end to the driver and another 1900 mm to open end.

I am looking forward to your comments. Hope you guys can help me tweaking this design.
 

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That looks nice. I wonder what the influence of the floor at the end of the line would be. I plan to do something similar after I rebuild the room, now I am quite happy with the Magnat Betasub30A BR, since my sound level needs are much lower.
 
That looks nice. I wonder what the influence of the floor at the end of the line would be. I plan to do something similar after I rebuild the room, now I am quite happy with the Magnat Betasub30A BR, since my sound level needs are much lower.

I was think about that too. In a former design it was straight to the front. I was just wondering if my kids would stick it with toys:rolleyes:
But I think a downward end won't be an issue as many enclosures have a port at the bottom or at the back.
 
Double click on Le to activate lossy Le. It changes The frequency respons quite some... Estimate if it requires remodeling.

Ignore post 8, I ment shorten L12, and lengthen L23 to about 120 and 210 cm.
Thank you very much Petter. You are very helpfull.

I read about the 'lossy le' thing, but still don't really understand what it is about. I have experienced it can screw up pretty much...
I read that you should use lossy le when Le>Re. So, in my case I should not use it...?

When I try to respect the lossy le thing my enclosure has to grow a little bit. Side effect is that I reach xmax at lower power.

But OK, after a 100 parameters, I think I can handle 101 too. Will play some more and try some more speakers.
Thanks again Petter.
 

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