Members agedhorse Posted November 8, 2005 Members Share Posted November 8, 2005 And to be honest, I do not recall the details, only that there are tradeoff's to be made. There was about 1dB of peaking in my design, so I will need to look at my paperwork to get better details. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted November 8, 2005 CMS Author Share Posted November 8, 2005 Originally posted by Steve_B Whilst I don Link to comment Share on other sites More sharing options...
Members kevinnem Posted November 8, 2005 Members Share Posted November 8, 2005 Originally posted by Dan Magers Four LAB subs here. No problem with the "real low end". Although, My back could use something a bit smaller, lighter. I have 6, .... need to make 2 more though Link to comment Share on other sites More sharing options...
Members Dan Magers Posted November 8, 2005 Members Share Posted November 8, 2005 Originally posted by kevinnem I have 6, .... need to make 2 more though A cluster of four is pretty impressive. Whats powering your 6? Link to comment Share on other sites More sharing options...
Members bilbo71070 Posted November 8, 2005 Members Share Posted November 8, 2005 I've ordered plans from Bill Fitzmaurice. He's a sound engineer that designed several different speaker boxes and sells the plans online. Normally, I wouldn't promote such a thing, but his forum is very informative, and he personally answers every question within 24 hours. Now, having said that, his plans aren't real explicit, and appear to be difficult at times to make sense. His subwoofers (the Tuba series) have really impressive specs and have compared favorably to some very expensive boxes. His web site is www.billfitzmaurice.com. Check it out, there's alot of information there. Link to comment Share on other sites More sharing options...
Members agedhorse Posted November 8, 2005 Members Share Posted November 8, 2005 Yes, we are quite familiar with his product. You might search on the subject here (try Tuba) and see what has transpired. He's a very knowledgeable guy, and the designs are solid, though not "trivial" to build. Unfortunately, some of his followers have tended to exaggerate claims to the point of being absurd, then get nasty trying to defend the impossible. It's too bad since I think Bill has a lot of good ideas and concepts, though the comparisons are a bit stretched for my tastes. Link to comment Share on other sites More sharing options...
Members bilbo71070 Posted November 8, 2005 Members Share Posted November 8, 2005 I wondered about that. I figure a few days in the woodshop and a few hundred dollars worth of speakers, I'll see for myself. If nothing else, I won't be out anything as the speakers I'll be using will fit in other cabinets that I do have, or I can use them to build other enclosures. Link to comment Share on other sites More sharing options...
Members Steve_B Posted November 8, 2005 Members Share Posted November 8, 2005 I hope that agedhorse doesn Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted November 8, 2005 CMS Author Share Posted November 8, 2005 Originally posted by bilbo71070 I've ordered plans from Bill Fitzmaurice. He's a sound engineer that designed several different speaker boxes and sells the plans online. Normally, I wouldn't promote such a thing, but his forum is very informative, and he personally answers every question within 24 hours. Now, having said that, his plans aren't real explicit, and appear to be difficult at times to make sense. His subwoofers (the Tuba series) have really impressive specs and have compared favorably to some very expensive boxes. His web site is www.billfitzmaurice.com. Check it out, there's alot of information there. I've got a pair of Tuba 24's I built almost a year ago, and they sit in my shop. I used the plan dimensions but built them properly with rabbet and dado construction. Don't expect much from the "plans". Unless he's upgraded since last year, they really should be freeware. Not up to anything I'd want to pay for.If you're interested in the 24, I'll be more than willing to sell you my boxes empty, and cheap...less than I paid for materials. They're simply painted black, but have a pretty nice dual Speakon jackplate I custom-built for them. Link to comment Share on other sites More sharing options...
Members agedhorse Posted November 8, 2005 Members Share Posted November 8, 2005 No problem Steve, this illustrates the limitations that every designer deals with. I haven't modeled or designed anything with the KiloMax so I don't have the experience with what the driver personally, but the 2241 is one that I do have experience with. Every driver has a range of box parameters that suit it well. It's the combination of box AND driver that define the SYSTEM performance, which is why "roll your own" boxes can be so dicey. Make some poor choices by not understanding the entire application process and you will end up with unpredictable results. The limitations of linear excursion is one reason why I do not buy into these "super-power" speaker rating claims. By the time you get to those power levels, you are tearing things apart for the long haul. You will end up with a floppy driver after the suspension components (really) loosen up with use. Link to comment Share on other sites More sharing options...
Members Steve_B Posted November 8, 2005 Members Share Posted November 8, 2005 You will end up with a floppy driver after the suspension components (really) loosen up with use. Mmm?? Variable Mechanical Compliance of Suspension (Cms). Just wait until the marketing guys get a spin on that. :D Steve.p.s. The kilomax figures and curves were just examples and not intended as a recommended design. I personally wouldn Link to comment Share on other sites More sharing options...
Members agedhorse Posted November 8, 2005 Members Share Posted November 8, 2005 Here's what I ended up with for myself: JBL 2241 10CF box 4 x 4" dia x 2" deep ports 1.5dB peaking at around 50-55Hz -3dB point at 39Hz No exceeding Xmax at 600 watts RMS the alternate design that I looked at was the same everything in a 14CF box, which yielded no peaking and a 33Hz -3dB point. This box design did exceed Xmax at around 45Hz but only by about 20% which may be entirely acceptable. An alternative is to use a 2242 driver which has an extended Xmax. Putting 1200 watts RMS (or 2400 or whatever the "cool" amount of power is today) into that box would be unbdesireable because of the Xmax limitations and also power compression wouldyield you very little additional SPL. Within it's 600 watt rating, it's ahell of a good sounding sub, especially clusters of 4 where the LF -3dB point is reduced somewhat. It's a deep, round, clean low end. Link to comment Share on other sites More sharing options...
Members agedhorse Posted November 8, 2005 Members Share Posted November 8, 2005 I can get good tunings 38Hz @-3dB for the KiloMax Pro in a box as small as 9.5CF, but it's a better performer in 15CF. I was able to achieve 30Hz @-3dB with no problem, but displacement is a big problem as you also noticed. Xmax is not as big a problem in the smaller box but only because I choose a more realistic tuning. That was using a 1000 watt RMS rating, which I personally feel is more than what's reasonable. Going back to 600 watts RMS and there's no real problem with either tuning. This shows the tradeoffs involved in a design that's sold into the marketplace and why spec's aren't always clear as there are multi-dimensional aspects to all specs. Especially when warranty issues are involved... do you sell off of one set of speca and honor warranty claims off of another set of specs??? Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted November 8, 2005 CMS Author Share Posted November 8, 2005 Originally posted by agedhorse Here's what I ended up with for myself:JBL 224110CF box4 x 4" dia x 2" deep ports1.5dB peaking at around 50-55Hz-3dB point at 39HzNo exceeding Xmax at 600 watts RMSthe alternate design that I looked at was the same everything in a 14CF box, which yielded no peaking and a 33Hz -3dB point. This box design did exceed Xmax at around 45Hz but only by about 20% which may be entirely acceptable. An alternative is to use a 2242 driver which has an extended Xmax.Putting 1200 watts RMS (or 2400 or whatever the "cool" amount of power is today) into that box would be unbdesireable because of the Xmax limitations and also power compression wouldyield you very little additional SPL. Within it's 600 watt rating, it's ahell of a good sounding sub, especially clusters of 4 where the LF -3dB point is reduced somewhat. It's a deep, round, clean low end. The 10CF box, with excption of different porting, is half a 4719, right? Link to comment Share on other sites More sharing options...
Members agedhorse Posted November 8, 2005 Members Share Posted November 8, 2005 Pretty close I'd imagine. Link to comment Share on other sites More sharing options...
Members Kennykeys Posted November 9, 2005 Members Share Posted November 9, 2005 Originally posted by Steve_B Back with the Eminence kilomax Link to comment Share on other sites More sharing options...
Members laidback Posted November 10, 2005 Members Share Posted November 10, 2005 "One approach that I Link to comment Share on other sites More sharing options...
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