PDA

View Full Version : Want my baby 4301s back



BeDome
04-01-2013, 09:05 PM
I want to have my 116H DRIVERS refoamed. Is there a qualified repair service known to this forum?

I think I saved the coils when I shut them down for the last time, but they have set unused for about thirteen years.

I am in trouble with these , but maybe someone knows where to send them to be properly repaired.

I welcome any suggestions.

macaroonie
04-02-2013, 02:53 AM
Hi there , You can do this yourself if you are careful.

First , check that the coils are ok. Use a meter to test , you should read approx 6.5 ohms. If you do not have a meter use a 1.5 volt battery and connect it on and off from the terminals. You should hear a noise if the coil is good.

Order the foams from here [email protected] Send him an e mail tell him what you need.

Read this sticky on this forum , its a step by step tutorial

http://www.audioheritage.org/vbulletin/showthread.php?469-Resurround-Step-by-step

Watch this video on You tube

http://www.youtube.com/watch?v=NImX51vFcxc.

You can probably omit the dust cap removal as Rick Cobb's kits come with a CD that allows you to check the coil is centered ( not rubbing )

Have fun

BeDome
04-02-2013, 08:37 AM
Thanks for the encouragement.

I have often considered this route, but honestly, I have so many great speakers to listen to ... blah, blah,blah

After reading here for a few months and finally becoming a member, I am almost ashamed to admit that I have such a rare treasure as a pair if 4301 Monitors sitting in such shape. :crying:

I have "held to my guns" mostly alone (I thought) as everyone around me disparaged JBL efforts. I am super hyped at finding a group of like-minded JBL users!


The hidden surprise in your post was bringing me to a long sought realization that Youtube can be "useful" for something besides a laugh.

Thanks!!
:cheers:

macaroonie
04-02-2013, 08:54 AM
Pleasure. One thing you might want to look for , if the drivers have sat in the same position for such a long time the spider may have sagged one way or tother depending on which way it has been oriented.
Get them ou and lay them on the magnets ,cone upwrds. Do they move freely without rub if you push gently on the center of the dust cap ?

Seen from the side the spider should look predominantly flat across the pleats. This is not a huge probblem and generally can be loosened up with gentle use to start with once you do the foams. The 30 Hz tone on the CD that comes with the kit is ideal for this. After a while you will hum along with it 8<))

4301 is a super little speaker BTW , absolutely worth bringing back into use.

M

BeDome
04-03-2013, 09:44 PM
I have found a number of sites that offer foam surrounds.

None of which can claim that they offer original equipment factory produced surrounds. Am I in trouble or is a foam surround a foam surround and I just need to shut up and buy what is available?

HELP!!

macaroonie
04-04-2013, 02:05 AM
JBL do not supply foam kits. Neither do they recommend re foaming , their position is that to rturn the driver to factory spec a re cone is required. Since the cone kits are probably NLA you do not have a choice in this matter.

Rick Cobb is the go to guy around this forum for foams , he supplies the correct item for your speaker. :)

mech986
04-04-2013, 04:30 AM
The 116H is the same driver as in JBL L19 as well. It's quite easy to refoam, just take it slow.

Carefully remove the neoprene front gasket because you'll reuse them later for a good OEM appearance. Good prep of the frame and cone by removing all the old surround, ok to leave a bit of the old glue. Test dry fit the surround to get comfortable with stretching it over the cone and how it lays on the frame. Then thin coat glue on the back cone edge circumference, spread, then affix surround, pressing surround to cone all around. Then play CD tone through low volume amplifier to center cone.

I use binder clips or clothes pins (if they hold) to temporarily place the outer surround down. If the tone plays fine, then the VC is centered and you can commence gluing the surround to the frame, I do 1/4 to 1/3 at a time, play, then continue gluing another part till the whole thing is glued, and the last test play is good. Then let dry x 12 hours, then glue the gasket on, and let dry another 24 hours for full strength. A last test tone to verify everything is good, then you can mount the drivers, taking care to get the correct polarity and wiring.

Good luck!

BeDome
04-21-2013, 03:19 PM
Thanks for all the encouragement folks.

In my youth I did some speaker reconing (in the early '70s), but it was mainly CTS, Kustom, Eminence, Celestion and no true factory parts were available to us. It was all about test fit all the various parts until you found a combination that seemed to work.

Once we became Altec and JBL certified in that store, I was already moving on to run my own sound company, but I do remember many of the "rules" that mattered.

I have now gained the courage to try this on my own, thanks to you guys.