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View Full Version : Questions about the D130 - 075 speaker -New here!



Davethreshold
07-07-2007, 07:57 PM
Hi all.

I bought 2 - J.B.L. 2-ways from an estate sale. ($75!! YE-Ha!) They have the D130, and 075 tweeter. Both are 16 Ohm. First, the 075. I just tested the tweeter with LinearX L.M.S. and I am astonished at how efficient it is: 113 D.B. @ 2.83V - 1 meter. The thing is, it starts to drop off at 15K. So I have a number of questions. First, is that drop off normal for this unit, (See pic 1) or did age limit it's top end? I remember back in the day, that I didn't think it went all ultrasonic like J.B.L. said.

2: Is there a rebuild kit for this, that would exceed this performance? I know that the modern tech, is a lot better than back then. I'm thinking with a newer coil/diaphragm, it might go higher. Also, what lens can I buy that would improve the dispersion? Would that be the 077 slot looking lens?

The D130: Kind of the same thing for this unit. The fO measures 49HZ. It should be 40, so I think the surround stiffened up over the years? I tried re-breaking it in at 10-15 Hz for a bout 1 1/2 hours. That didn't make any difference. Can I have it upgraded to a more modern unit with a re-cone?

Any feed back is certainly welcome. Ever since I started DIY speakers a few years ago, I always wanted a pair of these. Years ago, I bought a pair of 001's brand new for $800 retail From Musicraft in Oak Pk. Il. - 175DLH salt Shaker mid, & I think the 0130? or LE115? Darn...I just can't remember the woofer number. The 001's were 2.5 cu' with off white grills, and spun aluminum legs that were about 5" high.

Dave

Zilch
07-08-2007, 12:15 AM
http://audioheritage.org/vbulletin/showthread.php?t=6368

New diaphragms are available, also cone kits for D130:

http://www.jblproservice.com/pdf/Transducers%20Parts%20List/Transducer%20Parts%20List.pdf

Contact your local JBL Pro Service Canter:

http://www.jblproservice.com/service/index.html

Robh3606
07-08-2007, 05:41 AM
Hello Dave

None of the ring radiators go ultrasonic, have substantial output above 20k. The 2402/075 drops off above 15K here the link to the spec sheet for it;

http://www.lansingheritage.org/html/jbl/specs/pro-comp/2402.htm

The 2405/077 would be the choice for increased horizontal dispersion and it will go up to 20K before it crashes. Uses a lighter diaphram to do that but also will not be able to go low enough to use in a 2 way. It's 8K and up for them.

http://www.lansingheritage.org/html/jbl/specs/pro-comp/2405.htm


Rob:)

Davethreshold
07-08-2007, 11:57 PM
Thanks a lot Zilch and Rob. Exactly what I'm looking for. As the Inet gets more crowded, I have more and more trouble finding stuff.

Yes look at the dispersion difference at 40 Deg. between the 75 and 77. Later, I'll throw on the T/S parameters that I've come up with. You'll see how it compares to J.B.L.'s published data on this site. I wish the T/S pars. existed back in the day that they designed all of this stuff.

I would love to hear the (woofer of your choice) crossed over to the 375, to the 077, out of the box like I saw on one avatar in here. It seemed like they discovered so many things that they just didn't know back then. Such as vertical alignment of drivers, rounding off of baffle edges, MDF with tons of bracing, actual acoustically optimized xovers, which I don't think they had back then. The list is endless. I've looked at some of the new gear, and the materials and performance is almost scary.

I'm proud to be a member of this forum! I have joined a bit of audio history.

spkrman57
07-09-2007, 07:01 AM
I'm proud to be a member of this forum! I have joined a bit of audio history.
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And we are happy you are sharing your experience here also!;)

Regards, Ron

Steve Schell
07-09-2007, 05:59 PM
Hi Dave,

I've never measured any 075s, but by reputation they are not particularly smooth or extended in response. The moving mass is pretty heavy for a tweeter, so the rolloff on top is to be expected I suppose. From your graph it looks like the spec would be plus or minus 3dB from 3700Hz. to 14kHz., not too bad really, and pretty close to JBL's published specs for the similar 2402H:

http://www.lansingheritage.org/html/jbl/specs/pro-comp/2402.htm

A funny story- at some point years ago someone in the factory discovered that the 075 would measure smoother if a dry ball point pen was run around the diaphragm edge to introduce a bit of a compliance. This procedure was then incorporated into the factory assembly process.

Davethreshold
07-10-2007, 08:45 AM
Hi Dave,

I've never measured any 075s, but by reputation they are not particularly smooth or extended in response. The moving mass is pretty heavy for a tweeter, so the rolloff on top is to be expected I suppose. From your graph it looks like the spec would be plus or minus 3dB from 3700Hz. to 14kHz., not too bad really, and pretty close to JBL's published specs for the similar 2402H:

http://www.lansingheritage.org/html/jbl/specs/pro-comp/2402.htm

A funny story- at some point years ago someone in the factory discovered that the 075 would measure smoother if a dry ball point pen was run around the diaphragm edge to introduce a bit of a compliance. This procedure was then incorporated into the factory assembly process.Hi Steve. Thanks, and that is a funny story. I've gone over some of your threads. You MUST have been in the bus. with them. Were you?

Steve Schell
07-10-2007, 09:38 AM
Dave, I've been an avid fan of audio and especially loudspeaker history for about a decade now. I am one of three co-founders of this site, which has been up for a bit over seven years now. I've been fortunate to meet a number of current and past JBL employees, including Garry Margolis who provided the 075 story.

Over the past three years I have been transitioning from a full time piano tuner-technician to a loudspeaker manufacturer. My partner Rich Drysdale and I founded Cogent Loudspeakers, Inc. to manufacture compression drivers and complete front loaded horn systems for hi fi and home theatre. It has been a gas so far, and eventually we may even recoup our startup costs!