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tarior
01-16-2010, 10:01 PM
I bought these from a Craigslist ad today. Weird combo of 2120, 2105 (I know, two midrange speakers) and an E-V T-35 with a ferrite magnet.
Story has it that the PO bought them from a man whose hobby was building speakers. I'm not sure what he was thinking, as the 2120 appears to be a guitar speaker not a woofer. He sprung the $$ to buy it new, I wonder why he didn't use an LE111, LE14, even as big as the cabs are, a 136 or 2235. Oh well.
All of the drivers look like new, now I need to figger out what to do with them. I guess I'm about a pair of 2440s and 2405s away from some 4345 clones.:D
Oddly, they don't sound as terrible as one might think. Just crank the bass knob fully clockwise and they sound acceptable at low volumes. The 2105 seems capable of prodigious output for a driver of its size, and it comes to get you when you turn up the volume a little.
The 2120 is crossed over as a woofer, and as such doesn't seem to have much output. I kind of like the sound of the ferrite T-35s, at least at regular listening levels. I know they can get a little rough when pushed.
Any suggestions for projects? I have 2245s and LE14As also.
The cabs are nice 7/8" thick plywood, about 4.6 cubic feet net volume.

Robh3606
01-17-2010, 08:56 AM
Seems like an odd combo. There is no real woofer in there. Attached is the 10"s spec sheet if you don't already have it.


http://www.jblpro.com/pub/obsolete/2120.pdf


Rob:)

tarior
01-17-2010, 09:16 AM
Thanks.
I looked it up after going through the catalogs trying to figure out which driver that was when I was looking at the ad on CL. I don't understand why the guy who built these didn't use an LE14, 124, or LE111 instead of a large, high output midrange speaker.
Unfortunately, the only use I can think of for the 2120s is to recone them as 2121 or 2122 and build some 4344 or 4345 clones. But I sure hate to cut apart good working speakers. I suppose a guy could always put in a Zobel to knock that rising response down a little.

speakerdave
01-17-2010, 11:39 AM
That cabinet is too small for the 2245, and the 2235 for that matter. It might be the perfect cabinet for a 14"-based four way using the upper three elements and crossover of the 4344-45. By the time you get a dog box, horn, crossover and some other stuff in there, it will be about the right size for a 14-1 when you can find them. The 14A will do for the time being, and so will the 2120, by the way.

tarior
01-17-2010, 11:59 AM
Yeah, I've got a 4645B and a line on a couple more 4645 cabs, so housing 2245s isn't really a problem. I've got a couple of LE14As with a line on a few more, and I have the capability to recone them into H-1s. I am aware that the AlNiCo magnet won't sound the same as the ferrite. According to WinISD, a 2235 will work in this volume tuned to 30Hz, but I don't have any 2235s, so that is moot. Reading the spec sheet for the 2120, I almost think I can forgo the mid horn and use it up to about 7k. Thoughts?