Does anyone know of any woofers, past or present, which make use of the Hyperdynamics dual-gap/dual-coil configuration OTHER than the JBL W1xGTi series and the JBL 2256G pro subs?
I've definitely got nothing against JBL, though I do find the ultra-deep WGTi series rather ridiculous for car use, and at least the W15GTi sounds as bloated in car as it models. (It does wonderfully when given enough breathing room in home systems, and while I've not tried it my hunch is that it would be an awesome dipole or U-frame woofer, too.) The living room HT subs are twin JBL 2235H's freshly reconed by my friend Gordon Waters of Audio Atlanta. They're 15's with 8.65mm xmax - which gives each woofer the Vd of ~1.5 Peerless XLS12's - and a 1.2mH Le due to the motor design and Faraday rings - in 160L low-Q vented enclosures that on the LCD give me 110dB from 20Hz up before room gain using 400W total power (2 NHT A1 monoblocs) and a 3rd order electric high pass at 20Hz. Or to be more accurate they will be my subs as soon as I get them back. (They're being done by a local cabinetmaker. I can do woodwork well enough to make something that's going to be carpeted in a car, but not something that I'll want to look at every day.) Right now the HT is anchored by a Jello 15W6 in a Bessel sealed box. It's decent enough but not quite up to the level of the rest of the system (Tannoy 8" Duals with crossovers my my design in Qtc=0.577 sealed enclosures across the front, KEF Q Compacts for surround and surround back).300Z said:Velodyne uses the same tech in their top of the line subs... i forgot the model #'s...
Are you looking at/for some DDD subs?
Why do you still skipping on the JBL drivers? just wondering...
Have you ever played with the Peavey Low Rider 18? Its specs are mighty impressive, and the price is amazing. I was going to do a pair of those for the HT, with an ELF/Linkwitz Transform type approach, but then Gordon mentioned the 2235H, a woofer with which I was not previously familiar. (I don't have a pro audio background; it's simple irony that my car system is populated entirely with "home" speakers and my home nearly exclusively with "pro" stuff.) I plugged in some numbers, and soon enough was asking him to do a second one for me...chad said:As for the ELF-Bag End Concept. I plan to build an integrated sub system this winter for my mastering room here at home. I have been meaning to for some time but this is the year! As hinted at before these systems suffer from extremely poor efficiency. <snip> I'll let you know how the ELF turns out, I plan to use an 18" driver, maybe even the current one with a little modification, an EVX180.
I've only started to pay attention to what's in clubs, but I see lots of BP bass around here. On that same general tangent, someday I might experiment with a building a riff on the bandpass, Dr. Geddes' Acoustic Lever. (See also JAES 1/99.) Or come to think of it a conventional bandpass but using PR's instead of ports might be a neat digression, too....chad said:Although they are a bandpass (I heard that moan!) many have said they really get at it! I plan to build 4 for my club rig sometime
I think you are better off with the 2235's, they have a mass ring and a very low FS. Neat drivers as are the 18" counterpart, the 2245. I happen to know where there are 6 empty 2245 baskets that could be calling my name I also believe that you can use the 2245 kit in the 2240 basket, I need to research that further. 2240 baskets are a dime-a-dozen!DS-21 said:Have you ever played with the Peavey Low Rider 18? Its specs are mighty impressive, and the price is amazing. I was going to do a pair of those for the HT, with an ELF/Linkwitz Transform type approach, but then Gordon mentioned the 2235H, a woofer with which I was not previously familiar. (I don't have a pro audio background; it's simple irony that my car system is populated entirely with "home" speakers and my home nearly exclusively with "pro" stuff.) I plugged in some numbers, and soon enough was asking him to do a second one for me...
Do let us know how the ELF experiment turns out. My favorite car bass subsystems tend to be a riff on the ELF concept, i.e. a good woofer (the Peerless XLS12 works beautifully) in a low-Q sealed box that has an Fc of somewhere around the intended crossover point, using cabin gain to give the overall FR a gently lifting trend. However, the one Bag End sub I've heard was in many respects a disappointment. It was at least seven years ago, an kind of light on Vd: a single 18" that I later learned had about 5mm xmax. To me it just sounded compressed when pushed with organ pedals. Kind of like the car subs Velodyne sold a decade ago.
I've only started to pay attention to what's in clubs, but I see lots of BP bass around here. On that same general tangent, someday I might experiment with a building a riff on the bandpass, Dr. Geddes' Acoustic Lever. (See also JAES 1/99.) Or come to think of it a conventional bandpass but using PR's instead of ports might be a neat digression, too....
Those Ureis look really neat! Is that an Altec driver? Speaking of which, have you seen the latest variation on the Altec 605 theme, the Great Plains Audio/Iconic 704, or the latest modernization of it, the BMS 15C682? The Iconic is a bit pricey for me, but the BMS is around $800/pr from Assistance Audio. I'm a huge fan of BMS's compression drivers, and while I've not heard their woofers on paper they push all the right buttons.chad said:Aaah, Another fan of concentrics. I use Urei 809A's at home. I need to try Tannoy's again. I was forced to mix on Tannoy LGM's for 3 years and that experience left a bad taste in my mouth for a while. I think I'm getting over it.
I've had no occasion to use the newest one, the H1333 with its updated wide-roll tweeter and (?) waveguide tweaks. However, I've used its two predecessors, the H1144 and T17RE-COAX (the difference between them is that H1144 has the newer Seas basket, with spider ventilation) and I've familiar with the variant Gradient uses in their Revolution (basically, Seas' "G" cone and an aluminum tweeter) as well. I've not played with them much at home. However, lots of my friends with older cars (i.e. pre-DSP and so on) are driving around with them in their cars, usually with the woofer run wide open and the tweeter with some riff on a 2nd order HP.chad said:Have you tried the Seas concentrics yet?
Let's see If I did quoting right I'm a HTML Newb.DS-21 said:Before getting into other stuff, I've found another interesting DDD-motor woofer. It's a JBL but a pro one rather than a car one. The 2268H is an 18" woofer with the DDD motor, neo magnets, and 23mm (!!!!!) of xmax. Le is higher than my 2235H's, but at 1.85mH still not egregious. Especially since each one will displace THREE LITERS, or twice the air a single W15GTi will displace. To be sure, its parameters aren't as ideal for home use as they could be. The most suitable home use seems to be an ELF-style enclosure. A 121L enclosure has a Qtc of 0.57 and an F3 of 77Hz. However, as mentioned by Chad above ELF systems require insane power. Even with 1000W you're not going to reach xmax even at 10Hz, though at 20Hz you'll get within 3dB of the driver's max physical output. (107dB vs. 110dB.) A huge ported box would be great fun, though. A 280L (10ft^3) mini-fridge would have an F3 in the low 30Hz range (assuming a lowpass of 80Hz) and it would need 300W to reach xmax (110dB) at 20Hz. Unfortunately, I have neither 2kW of power available nor room for 25 cubic feet of subs, so right now it doesn't look like an outstanding choice for my application. The search goes on, albeit half-heartedly.
Urei is a JBL thing I think 'ol Jimbo lansing brought the technology over to JBL. The larger Urei's (15's) are VERY altec-ish the 12's like mine are a tad different with a foam surround, etc. The 15's are a 604 derivative. The horn lips are foam lined to deal with edge diffraction and the left and right sides of the waveguide are treated to reduce honk/FFT response.DS-21 said:
See how they put a super tweet on some of their newer stuff? There's a reason The LGM's were prolly from the early to mid 90's They had NO bottom, none, zilch. They had no highs, none, zilch. They had ton's of midbass, and tons of upper mids. They gave me a headache! Even trimming out the highs on the front panel, which incidentally, my boss hated me doing. They still sounded bad and I was amazed that the Ureis sounded so good for an older design. They are long gone, we sold them for a tremendous amount of money (in my taste) and now use Genelec in one studio, Meyer in another, and Mackie's in the third. The Meyers are my fave! MMMMMM so easy to listen to! I think I even like the Mackies over that particular Genelec! But as you said, maybe I just did not like the LGM's, many do, if the shoe fits.......DS-21 said:How old were the LGM's? I ask because most Gold’s and other alnico-magnet Duals that fall into the hands of people with measurement gear seem to be pretty severely demagnetized by now. Or maybe you just didn't like 'em. I've never heard vintage Tannoys, only the newer ferrite-magnet Tulip waveguide stuff, so I have no idea what the old stuff sound like.
No Brandsmart around these parts. I'll check the web, looks cool!DS-21 said:That said, if you have a Brandsmart USA near you it would be worth seeing if they have any KEF Q Compacts available. You won't get the satisfaction of DIY but you'll get better sound for a lot less money. In their Atlanta store they were clearing these speakers out for $55ea, including tax, and within the dynamic limits of a 5.25" midwoofer they're extremely good. (I went into the store for a new toaster, heard them across the way, and walked out with four for my surround channels...) The Q Compact absolutely slaughters the Seas (except for the H1333, perhaps, as I've not heard it) in HF clarity and extension, and is literally competitive with any dome tweeter I've yet heard. It has better directivity control through the midband than the older Seas drivers, because their tweeters couldn't quite get low enough to match the directivity of the woofer. (The H1333 appears to have fixed this problem.) Its motor is also superior to the Seas units, with an undercut polepiece and Faraday rings. Below are some pictures of the little driver. Below are some pics of its driver. (Mercifully, in the speaker the driver frame is covered by a black trim ring.)
Thanks, after time it just seems that you amount more and more stuff, I' not a big seller As for your abilities, it sounds like you have got it together, know how to weed out the ********, and have a solid understanding. That in itself commands the respect from myself and I'm sure many you speak with. Good job! Keep it up!DS-21 said:In all, it looks like you've got some neat stuff going on, and certainly more advanced abilities than someone like me. (My competence basically stops at and designing cabinets, modeling/assembling crossovers, and evaluating the end results of my efforts and others.) What kinds of stuff do you record?