Looking about for suitable drivers, any ideas?

This is a possibility

15" Bass Unit

Edited by user 29 June 2013 16:34:02(UTC)  | Reason: Not specified

Another name popped into my head. Apparently one of the largest driver manufacturers around

fostex

Pete,
Please do ask, this is what these forums are for. I am happy to be wrong or right!! I welcome any other thoughts.

With an OB its not what you're getting so much as what you are not. No box. No reflected sound within the box, no sound reflected through cone, no getting the right fill in a box, no fine tuning of box size, no real worries about box colouration, simple construction (but still paying attention to detail), no worries about sealing a box.

I understand you get sound all over the place with an open speaker. With the Visaton I linked to it uses a full range unit for everything above the bass so you will get beaming up through the frequency range. But I think you get a bit of uneveness in the FR out back as a midrange in a 3-way also beams. If I go for a 3-way I might have a rear facing tweeter padded down to add some air as some posh speakers do.

Back to the dipole bit. You get a figure of 8 dipole rather than full spherical down to the frequencies bass rolls around an open baffle, 100hz ish. This will be familiar to you with your MLs. Hassle to get working in a room, yes.....I have some room in the living room, it is a 30' foot long, 16' wide sixties living room (full of floor standing ceramic pots at the moment but that changes, I pretend they are helmholtz resonators).

You do need some efficiency with the drivers but people report success with Eminence etc instrument speakers/PA- Precision Devices for another example. But you can get this efficiency quite cheaply if you are prepared for a speaker with one or two 15" drivers a side. This is where it gets tricky domestically, at least you can see through your MLs

But why OB? When I were a lad and taking things apart a bit more I heard a great improvement in sound when I took some drivers out of boxes. I was also taken aback the first time I heard some Wilsons with their lack of cabinet sound. One of the advantages of ESL is their lack of a closed cabinet (taken hybrids). And the idea appeals. I have heard the big Jamos and liked them. I still havent heard the Gradients but look at the review in the Critic and they are distributed by DNM over here- now that is a man/company who know a good speaker when they hear one. I mean you Rehdeko.

This is the main source for the whys and wherefores.

linkwitzlab

The italian firm B&C make some excellent large units, short throw high spl, excllent cooling, linearity and durability. No uk distributor but you could try and buy from the continent?

If money is no object then get some custom units from Audiotechnology

audiotech

You can order up the exact spec you want but you end up paying about £600 each for a 15"

As a newcomer to this forum I am a bit late on this thread. Have you already got the bass drivers?

I expect you know already that there are many ways to move forward from conventional subs to dipole subs to servo subs to subs firing into a corner using DSP.

Can you tell us what the intended application is and the budget?

I have checked that out in many different enclosure options. This is one of the most suitable drivers I have seen with suitable characteristics. A large sealed enclosure works out absolutely fine for me

for speedy bass , not necessarily the most bass, I favour Qtc at 0.5 to 0.6 for a sealed box.

Thus I would trade , for a given allowable box volume a 12inch for a 15 inch to achieve it.

I am wary of too much equalisation and electronics ahead of it as with more supplies, power noise, extra ground routes

immediacy and fidelity may be impaired in favour of a notional text book frequency response.

The box size implies lots of panel area, so massive bracing and damping is a prerequisite if the journey is to be worth the effort and expense.

Martin Colloms

prefer slightly limited low bass but clean and quick, to equalized and overcooked bass extension

Very big speaker bass can be addictive but they are hard to set up for an even overall balance and fast timing

Martin Colloms

Resurrecting this thread

Budget and use. The intended use is for a full range 3 way design I have plenty of mids and tweeters lying around the place so selecting these will be easy!!

It is fixed that the project will be a sealed box that's it!

Budget around £300 per bass driver I will be selecting a low Q design so they will end up working in a large box around ~ 200L +

System Q = 0.6 ish