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analog addict
09-29-2006, 10:19 AM
Greetings from a new member,
Awhile back while I was wandering through the local goodwill store, I spied a pair of JBL speakers for $30. Figuring this would probably be a good gamble I picked them up, and found out I was the new owner of a pair of very nice JBL 4301b's. However, while working them over at home, I discovered the tweeters were both blown, and weren't even the originals to start with. On the recommendation of a knowledgable friend of mine, I replaced the blown tweeters with a pair of Morel MDT-28s. The response curve is similar to that of the MDT-29:
http://www.madisound.com/pdf/mdt%2029.pdf (javascript:ol('http://www.madisound.com/pdf/mdt%252029.pdf');)

I also refoamed the woofers with a kit specific for the 116H driver. Now, the question is, looking at the response curve for the MDT -28/29, should I replace these tweeters with a pair of LE-26's, and what is a fair price for a pair of used ones? What would an approximate value be for a pair of these in good shape with or with out the original tweeters? How different is the sound?
Thanks in advance....

A.A.

boputnam
09-29-2006, 11:00 AM
I would certainly go back to JBL standard issue for all components. These are darn near perfect two-ways...

majick47
09-29-2006, 09:00 PM
I havn't heard any Morel tweeters but I do have 4301b speakers and the LE26 is the tweeter that belongs there. Other than a thrift store or Craigslist find where the seller was clueless I doubt you will ever purchase a pair for less than $150. Since you have only $30 plus the refoam invested purchaseing a pair of LE26 to make your 4301b right you will still be around $100 total. Check Ebay for LE26, estimate $30-$50 for a pair.

analog addict
10-02-2006, 05:43 AM
Well, as luck would have it, I just picked up a pair of LE-26's on ebay last night for $25 +10 S/H. Not a great deal, but fair it seems. :applaud:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ih=009&item=190035053331&rd=1&sspagename=STRK%3AMEWN%3AIT&rd=1

Does anyone have any comments or suggestions for the dented cones/dustcaps?

I hate the aesthetics of dented speakers, but have heard it doesn't hurt the acoustics. I have also been told that you can pull the dents out with a small piece of duct tape, or a coffee stirrer + poster putty for a seal + sucking as hard as you can while pulling on the dent. I dont want to "f" them up though....

Thanks,
Allan

SEAWOLF97
10-02-2006, 10:39 AM
have heard , havnt tried, but the rumor is that you can suck them out with one of those attachment knozzles on your vacuum.

try on junk speaker first .....place over cap , then turn on vac, turn off vav , then remove knoz.

grumpy
10-02-2006, 11:05 AM
1) the dome is never going to be like new, the creases have broken the fibers in the paper

2) you might be able to make it look a lot better.

3) you certainly can make it a lot worse.

What I'm tempted to try follows (-NOT- a recommendation... if I actually do this,
I'll report back):

Shape some screen material to match good dome, put this in small vac nozzle,
dampen dome a bit, turn on vacuum (not full vacuum unless needed),
check progress... without a screen and with full vacuum, I would not expect a happy
ending.

If shape is OK, maybe find something that will soak into paper (thinned varnish?
airplane dope?) in an attempt to help restore paper stiffness.

Comments before I ruin an LE-25? :D

-grumpy

John W
10-02-2006, 12:15 PM
I've sucked more than a couple of LE-25 domes out with good success. Carefully apply a little water to the dented dome with a paint brush, then suck it out with some clear PVC tubing of the correct diameter. If you can get a good seal, lung power is easier to control than a vacuum, otherwise cup the tubing between your thumb and index finger and loosely put the other end up to the attachment nozzle.
I wouldn’t worry about trying to stiffen the dome up, unless you see some sort of problem.

Zilch
10-02-2006, 01:55 PM
I hate the aesthetics of dented speakers, but have heard it doesn't hurt the acoustics.Of COURSE it does; that's a major joke around this forum.

It doesn't take a genius to figure out that the uniform dispersion of those frequencies it emits is adversely altered.

If it's L100s, and you're playing max SPL air guitar with panties on your head, it's not likely to matter.

But if you're actually LISTENING....

Anthony L100
10-02-2006, 01:57 PM
John W, that is the best method i've used with excellent results. A vacuum is much easier, just cut a small hole in the tube and regulate the vacuum with your digit over the hole! I actually use 1/8 inch ID neoprene clear tube, works a treat.

Grumpy, airplane dope stiffens it up nicely.:D

John W
10-02-2006, 02:03 PM
just cut a small hole in the tube and regulate the vacuum with your digit over the hole!
Great idea, I'll try that next time.

takenodisk
10-02-2006, 06:34 PM
Glad that zilch point out the fact that a dented dome has an incidence on dispersions cos so many people(sellers) comforted me at the idea that 'no sonical alteration could be noticed':bs: now i'm warned;)

analog addict
10-03-2006, 09:30 AM
LE-26's will get here on Thurs. It seems that the duct tape idea isn't real popular. I will try a little suction. I do happen to have a small wet/dry vac in my listening room waiting to be converted into a vacuum record cleaner. Perhaps that will do the trick....
Thanks to all who responded....
Allan:applaud: