New compact bass design

I don't think it will need a delay - tapped horns usually don't (iirc). 

My knowledge is very patchy, just learning on a 'need to know' basis but if I understand horn theory correctly it should be very efficient when used in multiples. As a single box it's an uninspiring 92dB/watt (86dB/watt at 59Hz so more or less like a reflex, but as you can imagine in multiples it starts to act more like one big horn with the associated efficiency that gives - and a not too shabby 1.5 metre horn path!

Note to self: Need to stop calling it a tapped horn. It's a tapped pipe. That's the line. No taper no horn.

p.s. dear Mr. Danley please don't sue, thanks.

About it being a transmission line - does that mean it should be modelled or expected to behave differently to the way hornresp suggests? I think a 'tapped pipe' is not a standard variety of transmission line.. having a taper in the air path does affect the response but I didn't think it dramatically effected  the behaviour of the box - lots of 'transmission lines' or tapped pipes are documented online with measurements consistent with tapped horn boxes, competing head to head in shootouts etc.

Also, thanks! I hadn't considered how it might be flexible with other drivers. It's just a shame the Tangband sub drivers are SO deep.. if they produced a shallow magnet 5 inch with 11mm xmax.....:D

Edit: It just occurred to me that in the current arrangement a small amount of the sound pressure from the back of the cone might end up going the wrong way.. (backwards up the left hand side) - there's some flexibility to move the driver forwards but that has a detrimental effect on the predicted response (not to mention the centre of gravity)

What can you suggest in reflex that would come close? A larger more efficient driver means a larger box and 10 litres external is the limit.

 

My first thought is that the size of the driver is going to obstruct a lot of air movement in the last part of the pipe, and as this is where half of the output must exit then that could be a concern regarding flow restriction.

 

Only one way to find out! If I built it I would not bother with screws. I would rebate all the panels about 2mm so that the build all located together nicely and then ratchet it around every axis several times using 90 degree clamps. I have built a couple of HiFi cabs like this before and it works well as long as you have the rebates to get everything together without too much drama. Couple of panel pins could help if you struggled with it disintegrating before you could get all the straps on.