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View Full Version : JBL 044Ti - one tweeter is notably quieter than the other, is that repairable?



Kreshna
12-12-2014, 03:02 AM
So I've just bought another pair (http://www.ebay.com/itm/171489337634) of JBL 044Ti tweeters, and upon testing them, one tweeter is notably quieter than the other.

I tested them in one speaker (the right one), so it couldn't be crossover problem. I also tested them twice for each tweeter, so it couldn't be loose connection or such. So it must be the tweeter. Is that any way to repair it?

Also, while we're at it, how to detach the JBL 120Ti's bass port tube safely, without damaging the tube or the enclosure?

Many thanks.

rdgrimes
12-12-2014, 05:38 AM
I'd suggest checking the DC resistance across the posts, see how different they are.

Kreshna
12-14-2014, 01:46 AM
I'd suggest checking the DC resistance across the posts, see how different they are.Sorry for the late reply, and thanks. I have measured both tweeters. The normal one measures about 3.5 ohm (https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-xfa1/v/t1.0-9/p180x540/10849778_10205668951829572_5388377076882641272_n.j pg?oh=022bc71e37dd8d6172a816cb8f120106&oe=553DE792&__gda__=1427239628_23b134a25d96dda167e875b2b047f3d 8), which seems to be pretty normal when compared to other 044Tis on hand.The quiet one, however, measures about 60 ohm! (https://fbcdn-sphotos-a-a.akamaihd.net/hphotos-ak-xpa1/v/t1.0-9/p180x540/1461566_10205668950709544_7922580759752289512_n.jp g?oh=e4998f63ce8279851c91419b8e4f1156&oe=550BA0A8&__gda__=1426786669_14f7d6f328ac20689fb397fc480e765 a) (the pic is blurry but the needle is at 60 ohm position nonetheless).So is it repairable? :(

rdgrimes
12-14-2014, 07:53 AM
Sorry for the late reply, and thanks. I have measured both tweeters. The normal one measures about 3.5 ohm (https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-xfa1/v/t1.0-9/p180x540/10849778_10205668951829572_5388377076882641272_n.j pg?oh=022bc71e37dd8d6172a816cb8f120106&oe=553DE792&__gda__=1427239628_23b134a25d96dda167e875b2b047f3d 8), which seems to be pretty normal when compared to other 044Tis on hand.The quiet one, however, measures about 60 ohm! (https://fbcdn-sphotos-a-a.akamaihd.net/hphotos-ak-xpa1/v/t1.0-9/p180x540/1461566_10205668950709544_7922580759752289512_n.jp g?oh=e4998f63ce8279851c91419b8e4f1156&oe=550BA0A8&__gda__=1426786669_14f7d6f328ac20689fb397fc480e765 a) (the pic is blurry but the needle is at 60 ohm position nonetheless).So is it repairable? :(

Sounds like a paperweight to me. You could try taking it apart and cleaning out the VC gap, inspect the VC carefully. Nothing to lose at this point.

Kreshna
12-14-2014, 09:52 AM
Sounds like a paperweight to me. You could try taking it apart and cleaning out the VC gap, inspect the VC carefully. Nothing to lose at this point.
I see. Well, do I need to rewind the VC? Or replace it entirely? Won't sound the same with the original, but I wonder if rewinding the VC could at least approach the original sound.

Anyway, while we're at it, has anyone ever detached the 120Ti bass port tube before? Is it glued to the baffle? What is the safest way to remove it? The enclosure needs a complete sanding job, and the fiberglass sheets inside need to be replaced as well. I think the bass port tube needs to be detached while the enclosure is being restored.

rdgrimes
12-14-2014, 11:32 AM
I see. Well, do I need to rewind the VC? Or replace it entirely? Won't sound the same with the original, but I wonder if rewinding the VC could at least approach the original sound.


Given the availability of used 044ti, I don't see any reason to talk about rewinding coils, not do I think its possible. A careful cleaning and inspection is called for though. One common issue is the detachment of one of the wires to the terminal post - at either end.

Sometimes you can score a pair of 18ti used for less than a pair of 044ti alone.

BMWCCA
12-14-2014, 02:42 PM
Sometimes you can score a pair of 18ti used for less than a pair of 044ti alone.
+1 :thmbsup:
Last pair of 18ti sold on Ebay went for $147.97 USD about five-days ago. :eek:

SEAWOLF97
12-14-2014, 05:43 PM
+1 :thmbsup:
Last pair of 18ti sold on Ebay went for $147.97 USD about five-days ago. :eek:

Pil is right ... I got my pair of 18ti's for 044ti spares here on the forum for ... AFAIR ...$165 delivered
and in original boxes.

problem with yours MAY be .... foam under the dome rots and drops flakes into the
gap ... not too hard to open them and blow it all out. there is a thread somewhere
here on how to do it.

rusty jefferson
12-14-2014, 09:29 PM
So I've just bought another pair (http://www.ebay.com/itm/171489337634) of JBL 044Ti tweeters, and upon testing them, one tweeter is notably quieter than the other. .......



The link you provided to the Ebay sale stated "perfect working order". Simply returning them seems the best option. Even if outside the sellers normal return window, most don't want negative feedback.

Kreshna
12-15-2014, 02:01 AM
Thanks for the reply, folks. I was actually afraid it was the diaphragm, but I hope it's just foam flakes as SEAWOLF97 mentioned. As for the ebay seller, he hasn't replied my messages yet.

Anyway, while we're at it, anyone know the best way to remove the JBL 120Ti bass port safely?

SEAWOLF97
12-15-2014, 09:05 AM
Thanks for the reply, folks. I was actually afraid it was the diaphragm, but I hope it's just foam flakes as SEAWOLF97 mentioned. As for the ebay seller, he hasn't replied my messages yet.


http://www.audioheritage.org/vbulletin/showthread.php?29325-044Ti-questions-Help-needed&highlight=044ti+help