Conearea in dipole speaker

[Jussi]

Hi,

I'd need a dipolewoofer to play up to 200Hz or so, propably using 4th order crossover. So far I've considered XXLS 12" closed cabinet models and few PA woofers. Two drivers on each side.

Now for example 12" XXLS gives just 3dB less punch than almost twice as expensive 15" PA woofers. Basically more Sd with less xmax and vice versa.

So, which way? 3dB is some difference sure but pricedifference is quite crusial. Is it worth 3dB plus less excursion with larger cone to pay almost twice the money?

What kind of dipolewoofersystems do you have and how well can they perform?

Thanks !

Jussi

[noodle_snacks]

I have cut the panels for a cheap jaycar venom H frame (got given two 15inchers might as well use them for experiments). I'll let you know what i think about it. I may build a U frame later for comparisons sake.

If the 15in woofers cost twice as much for 3db more output, then why not get two 12in drivers, with the option to add two more (if you need the additional output), I believe you should get a 6db gain going from 2 to 4 (depending on how things are respective to the amplifier). You would get the added benefit of stereo subwoofers in this case.

[Jussi]

Noodle,

Yep but like I said, it's just two driver setup if I don't come up with something different approach and driver placement for it. Basically WWMTM. And the system is in stereo as it is.

Personally I consider double the cost 3dB pretty expensive but would I have some advantage of having about twice the conearea (with less excursion capability)?

Jussi

[jdunham]

Hi there,

I think there is never a substitute for cone area for dipole bass (or any bass speaker for that matter!).

Here is what I use:





Its my opinion that a mid cost 15" PA driver would give you better performance than the Peerless 12" driver. When I was looking around for my set-up I found that many "hi-fi audio" drivers were more expensive comparatively than PA drivers.

I've been really pleased with my set-up and had some good comments from a number of people who have heard them.

Kind regards,

Jonathan

[sreten]

Originally posted by jdunham

I think there is never a substitute for cone area for
dipole bass (or any bass speaker for that matter!).
Jonathan

Hi,

The same can be said for excursion capability, one without the other is no good.

Generally one would expect for the same swept volume the larger cone area
would be less distorted due to lower excursion but this is not always the case.

/sreten.

[sdclc126]

I don't know if they would make an appropriate dipole application, but Peerless makes a 15" SLS woofer - 830867 - less excursion than the XLS but probably more than most PA drivers. The SLS line is also considerably lower priced than the XLS.

Details at www.tymphany.com

They are listed in the Madisound catalog but not on the website, and the catalog doesn't list a price (I think they are a relatively new model), so you will have to email them.

[Jussi]

Jonathan,

Those speakers look fantastic. What are those woofers? Seems to be around 15" size? I guess I can have similar products from Finland as you invest from UK, I don't see that much sense ordering some special stuff across atlantic since there are many distributed brands at the old continent.

How extended bass can you achieve with those? How do they sound? Baffle seems to be turned a bit to the side, exactly the idea I thought to use since it's possible to play around with dipole 8 pattern against roommodes.

sdclc126,

I've asked for those from Finnish DST distributor but the 15" model isn't for DIY market just yet and there is no timetable when they will be...

Jussi

[sdclc126]

Originally posted by Jussi
sdclc126,

I've asked for those from Finnish DST distributor but the 15" model isn't for DIY market just yet and there is no timetable when they will be...

Jussi [/B]

That's too bad - Madisound should take it out of their catalog then.

BTW - yes those are great looking speakers and serious looking woofs - love the pipe design too.

[sqlkev]

One more thing other than the total displacement (cone area X excursion), you have to consider mechanical noises too.
PA drivers generally have very limited throw. I think most would perform fine within its limit, up until a bit of throw is needed. Plus, don't most of them have low QTS and highish FS? Extensive EQ will probably be needed.

IMO, grab 2 pairs of the dayton RS 15". One pair per side is probably more than enough for even a large room.

And if you're not afraid of going real big, consider trying the Mach5audio 18". There's a short review of it somewhere and it's positive. (real cheap too)

[jdunham]

Hi Jussi,

Those speakers look fantastic. What are those woofers? Seems to be around 15" size? I guess I can have similar products from Finland as you invest from UK, I don't see that much sense ordering some special stuff across atlantic since there are many distributed brands at the old continent.

Thanks for the compliments.

The drivers are Lambda TD15's that were bought in a group buy when they were going cheap! Having said that, I had looked into a number of other dirvers easily available and would have bought either Precision Devices or Beyma, they are readily available and reasonable priced (even secondhand).

How extended bass can you achieve with those? How do they sound? Baffle seems to be turned a bit to the side, exactly the idea I thought to use since it's possible to play around with dipole 8 pattern against roommodes.

Because of the corner positioning and my room, they don't require any EQ, and are surprisingly flat down to 30hz. They sound superb, very clean, fast, and no hint of overhang. The lack of room interaction is a revelation compared to all other types of bass loading I tried in my room. The corner loading was a bit of an accident until I realised what was going on - I originally designed the angled baffle to minimise the footprint!

Its a shame you are so far away, as you'd be very welcome to come and listen.

Kind regards,

Jonathan