JBL D140F (I found two NOS)

[Jim C]

I was stage manager for a Dead show at University of Maryland in about 1980 or 81'.
I remember a conventional flown PA (hung by a legit, local rigging crew) and the PA may have been supplied locally by one of our (back then) large touring companies. The hall was horrible (10,000 seat gymnasium) and I never much cared for the band.

They caused me a huge hassle with the fire marshal when they (without any previous knowledge) brought in a propane powered residential stove. They threatened to cancel if they couldn't have their cook prepare food backstage without his range! It did eventually happen but it was such a joke to see grown men acting like children. If it wasn't for the revenue it generated, I would have preferred a cancel.

 

[Mosthigh]

Huuh. I stand corrected. I've been laboring under this misconception for a LONG time. Dang.

Also, the Wall of Sound was built in 1973, and maybe early '74, so the cabs couldn't have come from a 1975 schematic. It's possible some of the bass cabs were rear ported, as are the modern 2x15 'Hard Truckers' cabs, (which may or may not still be in production), but I'm really not sure. My friend has a cab from the original WOS, but I saw it like 10 years ago, and can't remember much about it. I'll ask him next time.

 

[Blues Bass 2]

The best I ever heard D-140F speakers sound was when the rest of my band were home and I was playing my Bassman 100 through my 68 Dual Showman cabinet in my basement probably 1972 . Using my Guild Starfire II the sound was just magical . When the band was playing too with three guitar players the magic sound went away , it got more distorted . The mids and top end were awesome but only up to a certain volume and the lows were great too . If I would have had two rigs like that it would have been different . The first time I could get loud volume on my open E string ( 5 strings were a few years away ) was when I got a Peavey short folded horn with a Cerwin Vega 18 like they used in Acoustics . The mids and highs weren't anywhere near as clear as the JBLs but they went low without breaking up at all . I used 2220s in Comunity horns in the late 70's for my PA and they worked great at that . I think a lot of the big touring companies like Northwest sound were using 2220s . Great speakers .

 

[AGCurry]

What about in general stereo speaker application? I have cabinets I can put them in but am kind of aloof on how to go about driving them correctly. I could just sell them, but I’d like to put them to use.

They'll certainly work pretty well for a stereo system, but not in what you'd call "audiophile" class. The vintage-hi-fi fans know that the speaker was designed for musical instruments, not high-fidelity music reproduction.

 

[Mosthigh]

The best I ever heard D-140F speakers sound was when the rest of my band were home and I was playing my Bassman 100 through my 68 Dual Showman cabinet in my basement probably 1972 . Using my Guild Starfire II the sound was just magical . When the band was playing too with three guitar players the magic sound went away , it got more distorted . The mids and top end were awesome but only up to a certain volume and the lows were great too . If I would have had two rigs like that it would have been different . The first time I could get loud volume on my open E string ( 5 strings were a few years away ) was when I got a Peavey short folded horn with a Cerwin Vega 18 like they used in Acoustics . The mids and highs weren't anywhere near as clear as the JBLs but they went low without breaking up at all . I used 2220s in Comunity horns in the late 70's for my PA and they worked great at that . I think a lot of the big touring companies like Northwest sound were using 2220s . Great speakers .

I too have a 68 Dual Showman cab with JBL K130's, but thinking of swapping them for D or K 140's. The K130's don't really work for bass, but I also think the dimensions are too shallow to be a proper bass cab in general. Obviously people have used them for bass with 140's, but, yes, would probably need a second rig to get proper volume without distortion.

 

[StereoPlayer]

This is a great thread. I like speakers…

 

[AGCurry]

Those Altec sectoral horns were pretty standard equipment up until about 1980 or so, when newer radial horn designs began to displace them. Rap those aluminum horns with a knuckle or something and you'll hear a distinct ringing at about 800 Hz -- that resonance gave this particular horn a distinctive sonic signature, IMHO. That horn, with the Altec 808 driver, was used in the legendary Altec A-7 horn-loaded "compact" theater speaker system, among several other models Altec offered.

That resonance does happen sometimes, but not always. If it does, putty or something like it can be applied to the horn to attenuate the resonance.

My road band used A7 Voice of the Theater speakers for P.A. in the late 1970s. Big, efficient (drove the pair with a 100-watt power amp), and good-sounding.

They are not the highest fidelity, but it's hard to beat them for stereo imaging and pleasant sound. I have a pair of Altec Valencias (Voice of the Theater in a furniture-style box) for music listening, and they are sweet.

 

[Redbrangus]

I have a pair of Altec Valencias (Voice of the Theater in a furniture-style box) for music listening, and they are sweet.

I think your Valencias would have the 811 horn, which is similar in appearance, but smaller than the 511 horn that was typical in A-7s. Those speakers aren't blessed with the horn-loaded woofer of the A-7 either -- happily for you, IMO. IME, the most resonant part of those old 511 horns was the flat interior aluminum wall that divided the horn's segments; those things rang like a bell. Applying putty there wouldn't be practical.

I'm only too familiar with the capabilities of the A-7; I embarked on my professional career (such as it was ) with a pile of already well-used A-7s in 1974 and used them intensely for 4 more years. They were great for their era, but they were already fairly archaic when I replaced mine. A part of what replaced those in my inventory were cabs almost exactly like the ones in the earlier post, the 3.75 cu. ft. JBL enclosures; 4 - 8 of those could fit in the truck space of just one pair of the Altecs and could be stacked up a lot easier. I can remember rolling those A7s into hotel ballrooms and having the folks who were producing the parties be just horrified at their appearance. They just LOOKED too loud. Ahh... good times.

 

[agedhorse]

I owned A2's and A4's... if bigger is better, I just won

 

[JimmyM]

Interesting thread. Surprised I didn't see it before now. A pair...man, think how good they'd sound in a 60's B-15 double stack! I'd buy them myself if I had endless resources and wasn't so happy with the Delta 15a's in mine.

 

[FSGrind]

Thanks everyone!

 

[DoctorDistorto]

JBL was kinda weird with their nomenclature, in 1978 I bought a pair of K-130's to put into some homemade cabinets; I went with the 130's because the spec sheet said they had slightly more high end. They worked ok but I figured I really should have gotten the K-140's after the fact.

So circa 1982 I sold the K-130's to another bass player (who wanted to replicate my rig only he bought an Acoustic 120 head which was a big mistake, just not enough power) and bought some 140's, which by this time were the E-140.

So JBL went from D to K (skipping E,F, G,H and I), but then went BACK to E for the replacement series for the K models.

Analogeezer

According to Harvey Gerst the D stood for the metal dome, the “F” in D-130F, D-140F etc “originally stood for Fender, since they were the largest purchasers, and at one time, the distributor for all the JBL guitar speakers.” Then there’s the D15S made for Sunn…even though it was just a relabeled D-130F.

According to the AudioHeritage.org website, Invalid Link Removed
the K-Series came out in 1971 and the “K” stood for the new Kapton voice coil formers. I know a lot of folks think the K’s came out later…75ish, but I have an original K-Series brochure dated 1972 which I will post below. There’s also a 1973 pdf K-series brochure floating around online.

Anyway, the E-Series was so named for Efficiency, according to a very late 1979 JBL document. I’ll post that below as well. I don’t know what the G means in the G-series, but the G-135a makes an awesome bass guitar speaker! And it weighs only 13.5ish pounds.

 

[agedhorse]

The F was commonly attributed to Fender but that was kind of after the fact.

The claims of higher power handling in the E series was actually somewhat (not entirely) misleading. They changed from continuous RMS to program power to remain competitive. The program numbers are 2x the rms numbers. The increased sensitivity was in part due to the stronger ferrite motor.

The aluminum bobbin didn’t last all that long, they went back to Kapton which was more dimensionally stable under temperature rise. The aluminum would blister and then rub on the pole piece.

The G series were intended for the guitar market, a couple models worked ok for bass.

 

[DoctorDistorto]

Hi Aged Horse! I’m new to the forum but I’ve read your posts for a long time.

Harvey Gerst has stated a few times that the “F” stood for Fender. It does make sense, the same as the “S” in D15S stands for Sunn. Since Harvey was the guy who developed the F-Series I’m inclined to believe him. At the same time, I have no doubt that you know more about speakers than I do, and if I remember correctly, you’ve had some training by JBL. Based on your experience, were there other things that the “F” stood for or was is random?

 

[agedhorse]

I went through the JBL service school in the late 1970’s.

My recollection is that F was assigned to the revision. Fender and others were having challenges with mechanical (and to an extent thermal) power handling failures. Because at that time, the bobbins were a form of treated paper, and the glues, adhesives, binders were not terribly stable. Under hard use thermal expansion and movement was greater than the right gap dimensions could reliably accommodate.

The gap was very tight in order to extract the last bit of efficiency at a time when amplifier power was very expensive (on a dollar per watt basis). The root cause was that the gap with was not forgiving enough so it was widened a few thousandths of an inch to increase the clearance. Turns out the real world efficiency penalty wasn’t as bad as feared, and reliability improved a lot.

Since coincidentally Fender (one of my former employers) was the largest MI customer for these drivers, the F revision became colloquially referred to as the Fender revision. It was easier to go with the flow, and I recall reading that Harvey had said the same thing also. Ultimately, it doesn’t matter because that’s how it become known as.

 

[JimmyM]

I went through the JBL service school in the late 1970’s.

My recollection is that F was assigned to the revision. Fender and others were having challenges with mechanical (and to an extent thermal) power handling failures. Because at that time, the bobbins were a form of treated paper, and the glues, adhesives, binders were not terribly stable. Under hard use thermal expansion and movement was greater than the right gap dimensions could reliably accommodate.

The gap was very tight in order to extract the last bit of efficiency at a time when amplifier power was very expensive (on a dollar per watt basis). The root cause was that the gap with was not forgiving enough so it was widened a few thousandths of an inch to increase the clearance. Turns out the real world efficiency penalty wasn’t as bad as feared, and reliability improved a lot.

Since coincidentally Fender (one of my former employers) was the largest MI customer for these drivers, the F revision became colloquially referred to as the Fender revision. It was easier to go with the flow, and I recall reading that Harvey had said the same thing also. Ultimately, it doesn’t matter because that’s how it become known as.

Why mess with a good legend?

 

[bridgebuilder]

JBL D-140F speakers sound really good for bass, but - as Agedhorse stated, they will not handle a lot of power. Also realize that these speakers are reverse polarity - black is positive and red is negative. Best to do the 9V battery test to be sure !! For many years I played through a couple of Peavey 2x15 cabs loaded with JBL D-140F speakers !

 

[bridgebuilder]

I have a set of JBL D140F-6 in a Bassman Cabinet pushing with a Bassman 50 head. I have them wired red positive/ black negative. How do you do the 9V Battery test? Or would you recommend reversing the polarity?

 

[agedhorse]

Generally the black is positive and the red is negative on that era BUT some recone kits reverse this from the original standard.

Absolutely do the battery test on each driver, it's not uncommon to find differences (if reconed).

 

[eddiemac]

I don't think it makes any difference which polarity is chosen (+ or -) as long as it's the same for multiple speakers. Let me know if I am wrong. I could be delusional, but it seems I remember thinking firing backwards (JBL's red to +) protected the speaker somehow.