I want to build a passive sub but the dimensions will be a bit limited due to the location in which it will be used, basically tucked between two large bookcases. The maximum width has to be 220mm and the depth 300mm. However I could probably go to 1000mm in height. There is plenty of design software out there but I would like a push in the right direction with regards to what type of design I should be looking at, ie, ported, transmission line, sealed etc. Because of the position it will be used in, all ports, drive units, horn apertures etc need to be on the front or bottom of the unit. Any help appreciated.
Consider a Ripole. RiPole Subwoofer
and look at the ripole threads here. Jazzman (I think he is Charlie M on here) has built a double, but I am building two singles, as I have very little room next to my Quads. And I am angling the fronts to fit in too.
and look at the ripole threads here. Jazzman (I think he is Charlie M on here) has built a double, but I am building two singles, as I have very little room next to my Quads. And I am angling the fronts to fit in too.
Interesting, I remember the discussion on the subject. What was the driver (manufacturer?) RBS 512, chosen by Axel Ridtahler.
No longer available, I believe. Jazzman (and I), use the Peerless SLS-315 Peerless 830669 SLS-315 12" SubWoofer Speaker
I haven't finished mine yet.
I haven't finished mine yet.
An interesting design indeed. What other configurations should I consider? A friend has dozens of drive units that he will part with for not a lot of money so I was hoping to find something suitable among his hoard. Chances are there will not be anything suitable for said Ripole design.
From what you describe as the position limitations, if I'm understanding you correctly, a dipole isn't suitable
Wasn't the position, shouldn't it be on the back/side of the listener, for the dipole, if I remember, or other?
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You should post the list of drivers you have available (brand & model). We can then identify adequate speakers types.
If the bookshelves are on, or near, to a wall, the ripole design is likely one of the worst choices. That's a dipole bass design and needs to be away from any boundaries to work best.
The 220mm limitation on the width suggests that the drivers will need to be fairly small, like the Tang Band 6.5" subwoofer drivers, for example. Using one or more of these in a slot-loaded subwoofer should work, depending on how much output you're looking for.
The 220mm limitation on the width suggests that the drivers will need to be fairly small, like the Tang Band 6.5" subwoofer drivers, for example. Using one or more of these in a slot-loaded subwoofer should work, depending on how much output you're looking for.
Yeah, at 66 L o.d., by the time even thin panels, driver, bracing is factored in there's not much less, so thinking multiple 6.5" sealed and DSP it.
GM
GM
Maybe I am asking for something that is difficult to achieve. It seems that what I am going to end up with is effectively a floor standing speaker but with only bass units. This is no too much of a problem as I am only looking for some bass reinforcement and not ground shaking home cinema bass. I have recently had to (temporarily?) retire a pair of floorstanders and have bought an oldish pair of mission bookshelf speakers out of retirement. I am really just trying to regain some of the low end I have lost.
Here an example of a TL Kit Baubo by Renato Lira of Brasil.
AudioKit | Kit Baubo – Caixas Acusticas
AudioKit | Kit Baubo – Caixas Acusticas
Attachments
Looks like an end-loaded transmission line design. Can work well, but could have limited bandwidth due to deep notch in output around 3*Fb. The notch can be reduced by offsetting the driver in the path.
How about a Daline? The original KEF B110 design would work if turned sideways. And if you can get a pair of Jordan JX92s they will go even lower.