JBL D130F Questions

[-reverb-]

Hey all.

I picked-up a set of JBL D130F's today and am a bit puzzled about a couple of things.

Did my due diligence of looking things up out there on them Interwebs but still have a question or two.

1) They are marked as being 8-16 ohms. Never seen a speaker like that. They ohm-out at around 6.2 for one and 6.7 for the other. Does this seem reasonable? What does the 8-16 designation mean?

2) Saw some on that auction site that advertised "low serial numbers". The numbers were over 10,000. What constitutes a "low" serial?

3) One of mine has a double-stamped serial. I have read that this was an improvement in the process and thus it was assigned a new serial number. At first I thought it may have indicated a recone, but that seems to not be the case. Both woofs have what I believe to be the correct 21057 cones.

4) Are all of these Alnico? If not, how can you tell?

Thanks for any answers you can provide.

 

[Sam Cogley]

All JBL D and K series drivers are Alnico (as far as I can tell, the later K series are identical to the Ds except for black frame paint). The E series were their later ceramic cousins.

 

[geiman]

D 130 f were made for Fender Guitar. They are built to handle the transients an electric guitar throws at them. They are OK for music but there are better choices.

 

[-reverb-]

All JBL D and K series drivers are Alnico (as far as I can tell, the later K series are identical to the Ds except for black frame paint). The E series were their later ceramic cousins.

Thanks Sam. Appreciate the additional data points. I will be the first to admit that I know very little about JBL gear.

 

[-reverb-]

D 130 f were made for Fender Guitar. They are built to handle the transients an electric guitar throws at them. They are OK for music but there are better choices.

Yeah, that's what I have been able to learn over the last few days. I was surprised to find them in some nice cabinets that originally had EV T35 horns along with the JBL's. The horns were long gone (along withe the X36 crossover) but the AT37 Level Control was still there (unhooked).

The guy had these built in around 1973 he thought. He gave me JBL and EV catalogs from when he ordered all the parts. The D130's were $102 back then.

Thanks for the intel.

 

[Sam Cogley]

D 130 f were made for Fender Guitar. They are built to handle the transients an electric guitar throws at them. They are OK for music but there are better choices.

The D130F is identical to the D130, except for a slightly wider voice coil gap that sacrifices a tiny bit of efficiency. The cones and voice coils are 100% identical.

The design was inspired by Fender (hence the "F"), but they weren't made specifically for them. Anyone could buy an "F" series driver from JBL. Harvey Gerst, the guy who designed the D130F, the D140F, and some other notable JBL drivers sometimes posts at Lansing Heritage and other sites, and his definitive history of those drivers is available there. Any stories coming from other sources are, quite frankly, bunk.

http://www.audioheritage.org/vbulletin/showthread.php?5142-Harvey-Gerst-D130

 

[-reverb-]

Interesting read Sam. Thanks for the link.

One of the coolest things I got from this guy is a brochure of all the JBL parts and components you could buy at that time - with pricing. It's small but folds-out like the old paper maps use to. All unfolded it is maybe 30 x 40 inches. One side has individual components, the other side has full speaker systems (like the Pargon, Lancers etc). Not sure if these are common or not? I have never seen one before.

 

[-reverb-]

Still curious about the 8-16 Ohm designation on the back of the woofer.

On that auction site, most D130F's listed are 8 ohm versions. Is the 8-16 ohm variant something that lends itself better to musical instruments?

 

[donprice]

One of the coolest things I got from this guy is a brochure of all the JBL parts and components you could buy at that time - with pricing. It's small but folds-out like the old paper maps use to. All unfolded it is maybe 30 x 40 inches. One side has individual components, the other side has full speaker systems (like the Pargon, Lancers etc). Not sure if these are common or not? I have never seen one before.

See if you can find a scan of of it at Lansing Heritage. If not, PLEASE take it to a local blueprint company (or copy shop with large format scanner) and have it scanned as a PDF file for your friendly JBL nuts. I bet you could make a few $ selling copies on that auction site....or at least get your scanning costs back.

 

[-reverb-]

See if you can find a scan of of it at Lansing Heritage. If not, PLEASE take it to a local blueprint company (or copy shop with large format scanner) and have it scanned as a PDF file for your friendly JBL nuts. I bet you could make a few $ selling copies on that auction site....or at least get your scanning costs back.

I have an 11x17 scanner so here's my shot at it for you guys...

 

[-reverb-]

Last 4 pages...



Now about that 8-16 Ohm specification??? Can someone clarify this for me

Thanks!

 

[Jeffery]

I hope you have better luck than I did on the Lansing forum. I picked up a pair of extemely rare 32 ohm 150-4b's about a month ago and went there looking for info. I got lots of looks and lots of crickets. Ak was far more helpful.

The first cricket that replied knows a lot about JBL stuff and was stumped, but as was mentioned in the thread that the tags might have been misprints or maybe they are just something nearly one off. If nobody knows, then they don't know.

I read the "subwoofer" thread here and all you really got was some chatter that was lacking on the Lansing Heritage thread, nobody here posted any more factual info about a 150-4B.

Sorry you couldn't learn anything about them at either site, but it's not the members' fault that they don't know anything about the drivers.

 

[Jeffery]

Last 4 pages...



Now about that 8-16 Ohm specification??? Can someone clarify this for me

Thanks!

Looks like the "Musical Instrument" speakers are listed that way, maybe it is because they were produced for guitar amps or such without a crossover - non-specific impedance high enough to work with tube amps of different brands of the day. Just my guess.

 

[-reverb-]

OK, so let's stay on the thread topic which is the D130F.

I know what is going on and still had trouble figuring out what your reply was referring to Jeffery. While I appreciate the input, if y'all want to talk about the other model or the Lansing Heritage site, please create a new thread. No offense intended, just don't want folks to get confused as to what we are discussing.

 

[-reverb-]

Looks like the "Musical Instrument" speakers are listed that way, maybe it is because they were produced for guitar amps or such without a crossover - non-specific impedance high enough to work with tube amps of different brands of the day. Just my guess.

Interesting.... that would make sense. Thanks Jeffery.

 

[Gudstufshevy]

The d130f's are coveted by steel guitar players. They came in either 8 or 16 ohm. I have a set I've been sitting on for a while now. Debating on selling them, or e-waving them in Zilches honor.

 

[Sam Cogley]

Straight from the horse's mouth:
http://www.audioheritage.org/vbulletin/showthread.php?15656-dual-ohm-d130

We always considered the "nominal impedance" as the trough between 200 and 400 Hz. Of course, we lied back then, calling our 8 Ohm speakers "16 Ohms".

When amplifiers came out with 8 Ohm taps, the easiest course was to simply relabel the speakers "8-16 Ohms".

http://www.audioheritage.org/vbulletin/showthread.php?10456-JBL-D120-reproductions/page3

While we did maintain pretty tight tolerances, our 16 ohm speakers were really about 8 ohms and our 32 ohm speakers were closer to 16 ohm. Why? To make them a little louder. Remember, these were tube amps we were feeding. If you have a big hunk of iron for a transformer, tube amps are a little less fussy about lower impedance loads. Later, JBL just added "8 - 16 Ohms" on the label.

'Tis why I invoked Lansing Heritage and Mr. Gerst's name in the first place. :thmbsp:

 

[-reverb-]

Outstanding! Never would have known where to look for it on the Heritage site.

Much appreciated Sam.

 

[Sam Cogley]

Just ran a Google search with some relevant terms, Harvey's name, and the following limitation: "site:audioheritage.org"

You can do the same thing to search AK, though the built-in custom Google search will do it for you.

 

[Jeffery]

Without going into detail you read things much differently than I did. To a bystander it may have looked like "chatter" but to me it was helpful information that I learned here.
Enough said as those drivers don't belong to me anymore.

Glad you got some info from it, even if none of it pertained to the drivers in question! :thmbsp: