multiple cheap 15" vs one expensive 15"

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For a first system, the above choices are within the scope. If you can cross well, they should be encouraging. (Note that they are screw on.)

I don't want to set your bar for you.. I could reasonably say these waveguides are acceptable, or I could be critical. I know this much..

Developing the crossover (properly) on a system like this is vastly more involved than for a dome tweeter system. I'd want to be comfortable that I was investing this work on a good subject.... on the other hand the second (overall) crossover gains from your experience.
 
Looks like those compression drivers would be worth a go, also one of the horns you linked, perhaps the 6512? The Mini DSP will assist getting a working project happening, I would also use a protection capacitor of maybe 30-40uf in series with the driver to protect it.

Remember you will also need an adapter as the drivers are flange mount and the horns are threaded.

Cheers, Matt.
 
Why not buy a bolt on horn? No need for an adapter. Seems counter intuitive unless you screw up and buy the wrong thing like I did. I had to go the other way round from screw on driver to a bolt on horn. Started with a PA speaker pole mount and went to town.
 

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a rough guide is to match the waveguide width to the woofer width, so you have a chance at matching directivity at the crossover point

That's good to know.

I'm probably going to play about with a few random dipole/bipole arrangements for fun with the drivers I have at hand first but from what I've read of waveguides they certainly have my interest. They make a lot of sense.
 
Re: the original post, I had good results using cheapish VFM Audio 12" ceramic magnet PA woofers (provided with TS parameters) with Deluxe Econowave HF section (B&C DE250 on QSC waveguide) plus EQ. The woofers aren't perfect though and do compress at loud volumes and only have approx 3mm xmax. I currently use them as stereo subs in 70L sealed/ported cabs (plug the ports for music) in a smallish room and get down to low 20Hz at moderate SPL (below 90dB) no problem. VFM audio actually has a sale on NEO 12 and 15" PA woofers atm.

DIY Sound Group have some good value waveguide and compression drivers solutions. Be sure to get good performing waveguides. If you don't like beaming consider a wide beamwidth constant directivity horn.

That Faital Pro compression driver you've highlighted looks pretty nice based on the factory plot and the one bench test I saw. It is probably worth a try if you can grab it for cheap but unless you've seen measurements of it on the specific waveguide of your choice, it's performance may be less than optimal (waveguides are often optimised for specific compression driver exit angles). That Faital Pro woofer looks great and probably worth the investment but you can still get great results and test different loudspeaker alignments with cheap components.
 
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Hi mrk7,

More good info! Thanks for that. I think we're on the same page regarding listening volumes and some of the cheap gear I've gotten from DJ City is actually surprisingly well made, the 8" woofers I got from them have massive vented magnets and though I've yet to stick in in a box they look very promising.

I actually pulled the trigger on the Faital woofers last night after a few stiff drinks. They're priced unbelievably well for Australia, used in some very good designs and I really can't find much negativity about them at all. I'm thinking a quick Manzanita design before maybe putting them in a large sealed box.

I'm a bit torn about the CDs in general as I've messed about a bit with bipole/dipole designs and enjoyed them. That laser beam focus I've been hearing about might be very accurate and hi fi but I'm not 100000% sure it's for me?
 
Controlled directivity horns give the very opposite of “laser beaming”, they have a very wide and consistent sweet spot. The dispersion is “controlled”, which when matched properly with the woofer, gives consistent sound on and off axis, which is more important than a lot of people realise.

Cheers,

Matt.
 
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Don't know about this laser beam thing. The speed of sound doesn't increase. The wavefront doesn't become pointy and dangerous. ;)

A good and properly set up waveguide doesn't sound different per se to any other worthy source.


Edit, maybe you're thinking about cheap disco speakers. Here the response is the problem, not the directionality.
 
Controlled directivity horns give the very opposite of “laser beaming”, they have a very wide sweet spot.

Matt.

Poor choice of words on my part. I meant they give a warts and all presentation? I might be more interested in something I can live with on a day to day basis? Big, dynamic, comfortable sound? I've looked at a few omni types in this regard.
 
Poor choice of words on my part. I meant they give a warts and all presentation? I might be more interested in something I can live with on a day to day basis? Big, dynamic, comfortable sound? I've looked at a few omni types in this regard.

My 15PR400/SEOS 15 is definitely the most listenable speaker I have ever had, in around 25 years in the hobby. The sound is incredibly smooth and listening is relaxed. Off axis listening is also good, in fact, most of my listening is done off axis :)
 
...pulled the trigger on the Faital woofers
Congrats!

I'm a bit torn about the CDs in general as I've messed about a bit with bipole/dipole designs and enjoyed them. That laser beam focus I've been hearing about...

I love dipoles and I get your reservations.

I'm a proponent of CD designs but even with a 90x60 deg QSC waveguide (which is considered fairly wide and constant directivity), the acquisition of extra clarity at the cost of reduced ambience is DEFINITELY noticeable. Some members have added ambient channels to their systems to create/restore more ambience whilst retaining the clarity/staging qualities of CD designs.

I'm thinking a quick Manzanita design before maybe putting them in a large sealed box.
Sounds like a great idea!
 
Dipoles scatter a lot more sound around the room whereas horns do the exact opposite and limit them to a certain dispersion pattern that is narrower than a simple driver on a baffle

tractrix and exponential horns are very 'laser like' in that they focus the treble too much for my taste, but a large constant directivity horn of 90 x 45 (think a K402) is by far my preferred sound distribution pattern. Almost like wearing headphones but you can walk around the room and it remains mostly the same
 
Well, busy week, everything speaker related on the backburner but I've remeasured my old enclosures and it looks like the faitals actually might squeeze in there? We're talking 5mm clearance though, it'll be tight.
I really want to begin cutting this weekend but I know well enough to wait until I have the drivers in my hot sweaty hands before starting, just in case they're a few mm out.

Whilst the temptation of that dynamic bass OB owners gush about is very tempting and I also adore the look of the manzanita and anything Wharfedale sfb like, the reality for me is that I probably don't have enough room to really let the monsters breath? I have, in the past, put a pair of wide range 8" per side on very large, asymmetric baffles to interesting effect (coloured/dynamic) but they lived in the middle of the room, not very practical.
I have a very large supply of this foam, I could potentially treat the rear of the speaker with? I think it would be pretty much low pass stuff? Anyone any links on semi open baffle speakers? Super leaky designs?

I've also ordered a minidspHD and calibrated mic. I already own the standard minidsp and a cheap little dayton mic so I've got the feel for it and think the extra connectivity of the HD plus the accuracy of the calibrated mic are hopefully worth the investment.
 

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