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View Full Version : Trash picked JBL 030 Speakers



Bucha
06-01-2012, 07:59 AM
Hey guy, kind of new with this forum stuff so bear with me. This past Wednesday, I came home from classes to give my mom a ride to work, and passed some speakers up on the side of the road. At first I didn't know what they were, but once I dropped her off and turned around to get a better look I knew what I was dealing with. They had the JBL black crossover pointed out to the road, and that was the only thing that caught my eye when I passed. After about 20 minutes, I got them loaded in my truck. There were a handful of 12ax7-12at7 tubes on the ground to but no amp. Long story short, got them home, opened them up..... Just about died.....

D130 coupled with the 075. Got my meter out and started to check impedance on each, all withing their 16 ohm range and with original wax seals on the 075's. They sounded amazing once I got them hooked up. Pots are a little scratchy but what do you expect for free??? I am a little young to remember back to the designs of the 60's as I was born in late 1993 so anything is a big help to me. This would be my second 030 system so I know a little bit about them. People really don't know what they are throwing out.

Now enough about my luck, I was wondering if anyone could clue me in on what the cabinets are modeled after. I know that they are home made and a fairly decent job was done on them so I figured that it was a replica cab of something. Cabinet dimensions are 24x30x16 width x height x depth. Currently have them hooked up to a home brewed system that I have made on the cheap side. The D130's are crossed over at 150hz from the subwoofers under each cabinet. And the rest is done through the original N2400 crossover. They sound amazing!!! but on full signal, the D130's sound a little "boomy" for my likings.

Here are some picture that I hope upload when this gets posted........ Again any info would be of great help!!!!! Thanks Guys




5587655877558785587955880

louped garouv
06-01-2012, 08:02 AM
sweet grab, i hope you enjoy them for a bit...
they look to be in really good shape...

congrats!

rudy sesztak
06-01-2012, 12:58 PM
Jbl once had a C 35 cabinet. It was the same width,and depth,as your cabinets,but 8" higher. Don't know of any other old JBL cabinets near the size of yours.-RUDY

Bucha
06-01-2012, 01:22 PM
When I first got it in the truck, that is the first thing I could think of. But if memory serves me right, the C35 had a 175 horn with a n1200 crossover and a wooden base.... IDK, must be a home brew enclosure.

Don C
06-01-2012, 01:56 PM
I have a Heathkit speaker that's much smaller, but with very similar cabinet detailing. So that might be from Heathkit also.

spkrman57
06-02-2012, 10:07 AM
I must live in the wrong part of Ohio as I never luck into such a find!

Great score, play them with tube amps so see what they can really deliver!!!

Regards, Ron

Bucha
06-02-2012, 12:27 PM
I must live in the wrong part of Ohio as I never luck into such a find!

Ya, I got to say that I was sure lucky! I found them up in Westlake Ohio.

mech986
06-03-2012, 12:23 PM
Nice score!

For the bass boom, you could try adding some additional fiberglass lining to all the side and back surfaces (1 to 3 inches thick) and/or add a loose 1 inch thick layer over the baffle vent (from inside). You could then experiment with adding additional layers or compressing the layers down. What that would do is damp the vent so that it works a little less like a regular bass reflex and more like an aperiodic vent like the Dynaco A25.

Baron030
06-04-2012, 08:13 AM
the D130's sound a little "boomy" for my likings.

Those are homemade boxes and the port looks a little too large to me.
I would recommend measuring the inside dimensions of the enclosure and the size of the existing port and then plug the values into a WinISD or BassBox 6 computer program. I suspect that the port is way too large and as a result is giving you that “boomy” sound. The easiest way to fix that problem would be to cover part of the port with some plywood or build a rectangular duct for the existing port dimensions. The software will tell you what new port dimensions to use.

WindISD Link: http://www.linearteam.dk/default.aspx?pageid=winisdpro
(http://www.linearteam.dk/default.aspx?pageid=winisdpro)
Baron030:)

Bucha
06-04-2012, 05:16 PM
Thanks for the info. I will have to try out that program when I get a chance and see what I can do to level out the bass. I figure that if I can get these to sound good on the lower end, they may show some potential to convert into a 3-way enclosure since I have a lot of room to work with in there. But that will be down the road after I fix the bass issue.