New kit speaker -perfect for other enclosures

[Scottmoose]

Though the existing design enclosure looks pretty good to me -more in a minute. It's from www.world-designs.co.uk This is the loudspeaker kit arm of the magazine Hifi World, in the same way as www.worldaudiodesign.co.uk is their amplifier kit and book-selling arm. Why they don't just sell the speakers under this banner like they used to the last time they had speaker kits available is beyond be, but there you go.

Anyway, it’s a nice fat aperiodic stand-mount using Seas tweeters (a standard or an Excel for about double the price!) and a 10” Seas bass / mid-bass unit. Designer is Peter Comeau, formerly of Mission. Now, I’m decidedly not a fan of recent Mission speakers –the treble will take your head off. But it looks like he didn’t like them much either, as this is about as far removed from those as you’re likely to get.

Looking at the response graph as published a month or so back, he appears to have gone for a touch of bass-lift at 100Hz to add some weight, before it rolls off in that classic aperiodic manner smoothly below that point. Not bad at all. Basic version: £215UK inc VAT. Includes drivers, crossovers, wire, enclosure design etc. The more expensive type retails at about £400. You can also order flat-pack cabinets for the astronomical price of £180, although to be fair, they are veneered.

It's the cheapest option that interests me though, as it's an excellent way of getting the drivers and a properly designed crossover for a decent price… you can see where I’m going can’t you ;-)

Let’s see what else we can do. Like an MLTL which will give us some bass-heft. The driver, by the way, is the CA26. Decent parameters for QW loading, nice paper cone, butyl surround, easy break-up modes, well vented, 25Hz Fs. Looks good to me!

Input into the latest version of Martin's MathCad worksheet slated for release next month:

[Scottmoose]

And here's the frequency response. You can flatten it out with a 1" long port, I went for the longer option to roll things off a bit below 100Hz to compensate for room-gain. I'm not pretending these will rival an MLTL version of the Thor kit, but for £215, plus, say £25 for the MDF, they are an outright bargin. That big driver should give rock plenty of heft, and the drivers and crossover are certainly good enoguh to do the delicate stuff very well indeed.

PJ Harvey should do especially well through these -'Water' from her 1995 Glastonbury set (you know: the one where she was leaping about the stage in full 'vamp' makeup in a mostly unzipped neon-pink catsuit with black wonderbra) ought to thunder suitably for example. For a smaller room the existing aperiodic enclosure is very good indeed in my view, but it's nice to have the option of 25Hz bass isn't it? Plus -the drivers are pretty good quality so the mids and highs should be as good as most anything commercially available under £1000. Bargin! I'm tempted myself to be honest.

Best
Scott

[Scottmoose]

Here's a more refined version that could strike a happy medium, being a bit more compact. It's an MLTL again, 42" long, 10.5" wide x 10.5" deep. 0.35lbs ft^3 stuffin in first 2/3 of the line. 3"x2.75" port 2" up from base on the front panel. Again, I wanted to roll things off fractionally below 100Hz -you can adjues this easily by altering the port length. It doesn't plunge the lowest depths but it's very sensitive and should shift massive amounts of air with that big, smooth 10" bass-driver. And as the units are pretty high quaility, it should sound excellent. Sorry about the square cross-section, but with a big drive-unit there's only so much you can do. Some damping on the inner panel walls should help there. Some bracing would be good too for the side panels, and Dave's favourite -the magnet of the driver to the rear wall, as is done in the regular aperiodic box as well.

[Ian J]

Hi Scott,
The reason this is being sold through World Designs is that World Audio Design stopped trading a while ago. WAD became independent of HiFi World a couple of years ago and just before Christmas seemed to have run into difficulties. Noel Keywood (publisher of HiFi World) has set up WD with Peter Comeau and is presently trying to buy back the amp designs and any remaining parts - the forum at world-designs.co.uk is the place for more info on this.
Has the x-o for this speaker been published yet? I thought they were only releasing detailed schematics through the mag. The basic non-Excel option apparently runs the midbass 'flat out' which should be good. If I were looking for a kit right now this would be very high up the list.
Cheers
Ian

[Scottmoose]

Aha! Now that is interesting. I tried contacting WAD a few weeks ago; that would explain why I couldn't get through. Hope they do manage to get the amps back, they were pretty good kits, all things considered. I've only bought the mag in a hit and miss fashion recently, so if they made an announcement there, I must have missed it.

XO[s] are next month apparantly. But you can tell a fair bit from the response, and some of the asides made. As you say, the basic version is only supposed to be minimal as the drivers frankly don't need much help in this regard (good). As far as I know, the more expensive version rolls it off, and has some filtering, exactly what I don't know, but PC isn't known for duff designs, even if the recent Mission's weren't exactly to my taste. Should do nicely.

I think I'll go for my own MLTL version though... ;-)

Cheers
Scott