Case for Discussion - Would a Single driver Manifold/MTB be better than Tapped Horn?

Hofmann's iron law: low, efficient, small, pick two.
I pick efficient and as low as possible, under 200 liters pr. box.

The driver volume reduces the port's center volume, creating a "venturi port" in the slot/offset horn.
Interesting concept. I haven't come by this one before. In the SB1000z you posted in #57, the drivers seem to be mounted close to the mouth of the OD horn and with the magnets in the chamber. Do you have an example of this venturi port driver concept?
 
Hofmann's iron law: low, efficient, small, pick two.
Since you pick a small chamber, the lower tune only exceeds 10% efficiency from 50-60Hz, while the higher tune exceeds 10% efficiency 55-70Hz.
Similar to a Cubo, or the mid 1980s EV SH-1810L-ER, seems too much of the small box is given up to the offset horn, sacrificing low end for mid-bass efficiency.
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You get to choose the efficiency ratio between the ranges.

It may be modeled like that, though what I described is an offset horn sharing the bass reflex port, making the volume occupied by the driver available to the bass reflex chamber.

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The driver volume reduces the port's center volume, creating a "venturi port" in the slot/offset horn.

Art

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I would dearly like to know how to model this alignment. Is it a tapped horn? Bill Fitzmaurice has a similar design (his Omni 12 and 15), and they certainly pump out some low end. There have also been some commercial bass guitar cabinets that have a tapped reflex port, which by all accounts sound very big for their size.

Whenever I model them as a tapped horn, they model like absolute rubbish. Perhaps I am doing something wrong.
 
I would dearly like to know how to model this alignment

It's a simple Band Pass 6th order Series or Tapped Horn.

Check the models below:

BP6S2
https://freeloudspeakerplan.rf.gd/pages/bp6s2.htm

TH-T18
https://freeloudspeakerplan.rf.gd/pages/th-t18.htm

Besides all those names, It's just about defining pipe length between the two chambers and adding flare or not in the pipe/chamber.

Sometimes people just create a layout of the same thing and give it a different name. In the core it's the same thing, different layouts help to better achieve different ratios from each parameter witch at the end can benefit some drivers to improve the output performance.
 
Port noise and motor/suspension noise altogether in one disaster ?

Looks like the port is big enough for the driver to fit in, so, port noise will probably not be a problem for this layout, motor / suspension noise, you need to consider at what driver displacement, lets consider Xmax, in that situation what would be the output SPL from the box? If they are 12dB different or higher in the same frequency range, it may not be a problem also, driver is also orthogonal to the port.


it doesn't look as a disaster for this particular case.
 
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I would dearly like to know how to model this alignment. Is it a tapped horn? Bill Fitzmaurice has a similar design (his Omni 12 and 15), and they certainly pump out some low end. There have also been some commercial bass guitar cabinets that have a tapped reflex port, which by all accounts sound very big for their size.

Whenever I model them as a tapped horn, they model like absolute rubbish. Perhaps I am doing something wrong.

It's just a BP6S or a straight flare TH with a compression chamber.

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