D130 Dust Caps Paper vs. Metal - Ripple tears

[Howe]

I see a lot of D130 drivers with the aluminum domed dust cap but yesterday I picked up a pair of 16 ohm signature series D130A's and they have the dark grey paper. The cones have the white JBL numbers on the reverse side. Can anyone tell me which D130s are supposed to have aluminum caps and which should be expected to have the paper types? I'm embarassed I don't know this.

Also, what's the impact of having one, two or three tiny tears in the outer ripples where the cone attaches? A friend of mine says its hard to find drivers of this vintage without a couple. Should they be left alone or given a dab of service cement?

Thanks,

Howe

[GordonW]

The 130A is supposed to have a paper dustcap. Different animal from the D130. Copper winding instead of aluminum, made for more bottom end.

I'd be inclined to touch up tears in the paper surround, with a VERY LIGHT application of rubber cement (just enough to get into the crack, and LIGHTLY cover it). Don't over-do it, because you don't want to make a stress point from it becoming too stiff, in that local area...

Regards,
Gordon.

[Don McRitchie]

For most of the 30 odd years of JBL's production of the "D" series drivers, the "D" referred to transducers with aluminum center domes that were intended for extended range applications. Within JBL the "D" became shorthand for "Dome" in all of their drivers with this prefix.

However, this was not always the case. For reasons that I have never uncovered, Jim Lansing named all of the drivers he originally developed with a "D" prefix. This included the D130A, which was his first true bass driver with a paper dust cap. It also applied to his first compression driver which he named the D175. It was only after Bill Thomas began running the company in 1950 that he changed the naming convention and dropped the "D" from all drivers except the extended range aluminum dome series. Thus the D130A simply became the 130A and the D175 became the 175 while the D130, D131 and D208 continued on as before.

[Howe]

Now that you mention it, mine are 130A's and not with the "D" prefix. That is an interesting dialogue about the "D" prefix. Nice to know!

Thanks for clearing up the aluminum vs. paper cap question. Great forum!

I'll consider the rubber cement touch-up. Service cement is kind of heavy duty comparably. I've noticed some of these ripple surrounds have been treated with a shellac or varnish. Mine are natural. Hence, vulnerable? Must be a common problem on older cones.

[Mr. Widget]

I've noticed some of these ripple surrounds have been treated with a shellac or varnish. Mine are natural. Hence, vulnerable? Must be a common problem on older cones.

Yes the earliest cones had a simple paper rolled surround like you are describing. Later they doped the surround and later still they added a rolled cloth surround.

I have seen plenty of old JBLs with the untreated paper surround still working fine some 40-50 years after they were made... though you are right, they seem to be more vulnerable and do tend to get damaged.


Widget

[BMWCCA]

I have seen plenty of old JBLs with the untreated paper surround still working fine some 40-50 years after they were made... though you are right, they seem to be more vulnerable and do tend to get damaged.

Like the ones in my living room—D130/075 in C37 cabs. Came in from working on the car and my wife had them cranked, listening to Jesse Colin Young while she worked in another part of the house. Sound just like they did when I was a little kid. (You should have seen me hauling them off to college in '73. I took the entire back seat out of my BMW 1600, covered the floor with plywood and stood the speakers on end in the back. Figured as long as they were inside with me I'd hook them up to the car stereo, too . . . biggest set of headphones I've ever seen!)
-Phil

[P.Warner]

I had always gone along with the idea that the untreated paper surrounds were from the earliest vintage. If, as I understand Don for the "130", the D was only dropped after 1950 yet Howe's example in plain paper is a 130A..sans the D. It all makes perfect sense until you think about it!

(You should have seen me hauling them off to college in '73. I took the entire back seat out of my BMW 1600, covered the floor with plywood and stood the speakers on end in the back. Figured as long as they were inside with me I'd hook them up to the car stereo, too . . . biggest set of headphones I've ever seen!)
-Phil

I thought I was the only one crazy enough to squeeze a pair of Altec 9844a's into a Volkwagen bug going to college and yes, I hooked them up as well!

[BMWCCA]

One of my D130 (non "A") was bought new (by my dad) in about 1955 and the cone is all paper (and the speakers are post-"Jim Lansing" labeling). The other was bought used in about 1969 from the same dealer and is the same vintage. I hope the reference to carting them off to college in 1973 isn't what threw you!

[Steve Schell]

It has been my assumption that in Jim Lansing's mind "D" stood for driver, just as "N" stood for network and "H" for horn. These terms were applied consistently to the late 1940s JBL products.