PDA

View Full Version : Jbl cone grade/slope



bldozier
01-14-2017, 12:05 PM
Just received my 2108. Thank you sir. Bit of drama as the woofer separated
frm the board it's attached too, shearing the zip ties
the terminals were also loose. Alls good.

Can anyone tell me the step or grade of the le10, le8t and 2108
cones75431

mech986
01-15-2017, 03:54 AM
Just received my 2108. Thank you sir. Bit of drama as the woofer separated
frm the board it's attached too, shearing the zip ties
the terminals were also loose. Alls good.

Can anyone tell me the step or grade of the le10, le8t and 2108
cones75431

Not sure quite what your asking, but all the cones and drivers are different - they were designed at different times, for different purposes and with different concepts.

The LE8T I believe is the oldest, dating back to the late 50's. Its a lightweight cone straight sided cone with a 2 inch voice coil and aluminum dome - makes it a relatively wide range driver capable of doing a little bass, and it forte is midrange and lower treble.

The LE10 was designed in the late 50's or early 60's, somewhat similar to the LE8T in a straight sided cone, 2 inch voice coil, larger cone of course, no aluminum dome - no pretext of trying to reach up any higher like some of the musical instrument / guitar JBL drivers. Does bass a bit better, can go into the low midrange, but not much beyond that.

Both of the above had the Lansaloy white, then yellowed surround which proved troublesome after a few years, and unless a stickler for originality, should be replaced with a modern foam surround of correct size, width, and flexibility - too stiff will affect the response. Both designed either by Ed May or Bart Locanthi for high sensitivity and easy of drive with older vintage amps of limited power output.

The 2108 as you have found out is a really specialized driver with late 70's / early 80's design (I think by Greg Timbers) - relatively lightweight ribbed cone with a bit of damping, super large 3" voice coil for an 8" driver with a very small cone of 6" diameter - meant for very fast midrange with punch and high output - a unique and modern driver, even today, and probably relatively expensive to build.

bldozier
01-16-2017, 05:08 PM
Ahh ok. Sorry.

Thanks for all the help. I will try an measure em
the old fashion way
brian.