Hi Everyone:
I'm almost 100% convinced that I'll opt for using the 3012LF in my next subwoofer build. Does anyone have any experience using this driver? Are there any other 12" drivers with a better performance/cost ratio? Any reliability issues? Any examples of them used in a DIY subwoofer (PA) design? A Google search doesn't seem to turn up much, and this driver has been on the market for at least eight years, which is curious...
I'm almost 100% convinced that I'll opt for using the 3012LF in my next subwoofer build. Does anyone have any experience using this driver? Are there any other 12" drivers with a better performance/cost ratio? Any reliability issues? Any examples of them used in a DIY subwoofer (PA) design? A Google search doesn't seem to turn up much, and this driver has been on the market for at least eight years, which is curious...
I Agree with Neo Dan, if you going to use it in (high) compression applications (TH/FLH) it is pretty weak on the cone. However for 2 way vented applications it is ideal thanks to the uprising response.
The 3012LF is not really a sub-woofer driver. I'd say it is more appropriate for a PA woofer system. For sub-woofer performance, the only real driver (from Eminence) that allows that possibility, is the LAB-12. A single unit, however, will not give you PA SPL levels. Hoffman's Iron Law. As usual, the design choice depends on your ultimate goal.
I know on AVS the B&C drivers are getting a lot of use there BL numbers are pretty high and some have a pretty decent excursion. Price is high though.
Sorry, I should have clarified. Yes, this is for PA duty, basically a ~40 Hz TH, though I'm looking at other possibilities.
For the previous responders, the existing TH I'm going to be using it in (while I work on the new design) is a TH with S2=256 cm^2, which gives an approximate 2:1 compression ratio for a 12" driver. The existing 12" driver is a Dayton PA310, which has a cone that's almost exactly the same weight at the 3012 LF's cone (72g). the PA310's shortcoming is the low (rated) Xmax, 5mm. The 3012LF's Xmax is 9.1mm, so should be capable of greater output, which is one of the things I'm counting on.
I haven't found another 12" driver in the same price range that works as well for PA 40 Hz TH duty, at least on paper, but I'm open to suggestions.
Concerning the BFM designs that use the 3012LF driver, I'm curious about any actual experiences with these. T/s parameters don't tell you anything about the reliability of the driver when used in FLHs....
I could be wrong but I don't think the Xmax rating for the PA310 and 3012LF are based on the same calculation. Based on a comparison of other T/S-parameters I think they're closer towards each other than the published ratings.
Johan
Johan
I've got a couple of thousand hours with my 4x T30 cabinets loaded with 3012lf. They have served me very well!
There is a certain way they work that makes most skilled DJ's tweak their sets to very bass/sub demanding songs as they handle everything thrown at them with ease and dig into the low octaves with great clarity which many has never heard. Still surprise me to this day in a way nothing has with the right tracks.
Nowdays I use two keystones and they make the t30's sound a bit weak, but they have a more wooly/hollow sound to them when the VC's are not warmed up, but get about 90% of the rapid clear sound when warm. I like trying new things 🙂
Don't know the CR, but I haven't blown a single driver and these cabs has had a hard life for sure! Only a tinsel lead has broken once.
Hope this helps!
There is a certain way they work that makes most skilled DJ's tweak their sets to very bass/sub demanding songs as they handle everything thrown at them with ease and dig into the low octaves with great clarity which many has never heard. Still surprise me to this day in a way nothing has with the right tracks.
Nowdays I use two keystones and they make the t30's sound a bit weak, but they have a more wooly/hollow sound to them when the VC's are not warmed up, but get about 90% of the rapid clear sound when warm. I like trying new things 🙂
Don't know the CR, but I haven't blown a single driver and these cabs has had a hard life for sure! Only a tinsel lead has broken once.
Hope this helps!
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Yes, there is a possibility that their Xmax ratings may be closer than published, though I think that's a small one. What I'm also looking for is info about how they handle being overloaded a little. The PA310 doesn't like it much - the cone can move about 8~10mm max in the forward direction (my observation) before the suspension brings it to a halt (the spider allows more forward movement, but now the cone itself is bending around its edge - not a good thing!). The 3012LF OTOH has a rated Xlim of 14.5mm, which is quite a bit higher, so it should behave a bit better.
Thanks Osse, that's exactly the feedback I'm looking for. Just to confirm, each T30 was loaded with one of the 3012LFs, right? If that's the case, I wouldn't expect four of them to keep up with the 2 Keystones, as each of those is loaded with an 18" driver, and they're more efficient down to 40 Hz as well. BTW, some damping between S1 and S2 might get rid of the "hollow" sound (if it's caused by resonances in the midbass area) without impacting its low frequency performance.
I'd love to try one of the B&C drivers, as their cones do look at bit more solid, but I haven't found one in the same price range that can deliver the same level of performance as the 3012LF (on paper).
3012LF specs are spot on for a vintage 30 Hz expo compression horn, so should be fine as long as you limit CR < 1.8:1 and approximate a ~30 Hz flare frequency.
GM
GM
Have a look at this page: JM-sub212 (LMB-212) - PA Kompakter Subwoofer - Bassreflex | Jobst-Audio - Tontechnik It's only in german, but there's a scheme how to build this cabinet. I have four of them (and one cut in half for a smaller system) in PA usage and I'm very pleased so far. [url=http://www.audiofotos.eu/display-i3386b6wy0a.html]
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Well, I am considering using it in an existing 2:1 CR design (my POC3) until I build the new TH, so I think I'll be all right. POC3 has a lower resonance frequency around 40 Hz, but some fiddling with Hornresp suggests that the 3012LF would give a better response with a wider mouth.
I've pulled the existing PA310 driver from the box. The specs of that driver suggests decent bass response at small signals, however the surround is reaching full extension long before the spider does, and the cone is not a very sturdy one. End result - bending around the edge of the cone where it is attached to the surround (sigh). I might try a diluted solution of aliphatic resin around that section to see if this can be mended without damaging performance too much. The 14.5mm rated Xmech for the 3012LF suggests that it will be a lot less likely to suffer from this issue.
The Alpines are beast drivers. I use two of the Type Rs (the dual 2 ohm versions) in my car. Capable of a lot of clean output. Unfortunately not efficient enough for my needs - I'm looking for something that can put out a decent amount of output (above 95dB/1W/1M) for most of its passband, and good from about 40 Hz to 120 Hz. Qts on the Alpines is a little high for my personal preferences for the high-order designs (THs, bandpass, etc.) that would be required to raise the overall efficiency.
The plastic dust-cover on one of my Type R drivers is cracking. I'm tempted to just pull it off entirely to see how much that reduces Mms, which in turn will raise Fs (good), raise efficiency (good), and lower Qes (good). BTW - I took them out of the enclosure recently, where they're mounted facing up, and there's been ZERO cone-sag. Zero. And these things have been living in the back of my car for over two years. My cheap PA310 driver in my POC3 design OTOH does show what seems to be noticeable cone sag. I'm betting the spider material is what's making the difference.
Nope - it's one-way rated. Xmech in the docs however is quoted P-P.
I've got the Klippel results for the Type Rs. Very impressive.
Thanks for this. Looks like a pretty good 2x12 PA subwoofer design with an Fb around 42 Hz. My POC3 design with one of the 3012LFs would have slightly higher efficiency using one driver, and the box is going to be a little smaller than that 2x12, but obviously the peak SPL output would be lower (because only one driver will be used.
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