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Neoman
12-19-2005, 09:40 PM
Well the speaker Gods are testing me looks like voice coil alignment is rough on one of my 136 Woofers, buzzing @ 120hz - 130 taming out @ 150hz. What do you guys think? Coil burnt?, warpped? both? and I thought 30hz for centering your coil was nonsense oops!:blink:

Oldmics
12-19-2005, 10:47 PM
The 30hz procedure really works.

How did you align it after refoaming?

Oldmics

Neoman
12-19-2005, 11:14 PM
Just did what I thought was necessary per OCS instructions push gently and listen for rubbing or scratching. Can I shoot myself now!:) I guess coil gap is pretty narrow? can you belive one out of the two 136's came out centered!

Guess I'm looking at recone? +shipping O.C.S:(

Better yet 40 bucks and 30hz sounds better or am I just blowing shipping down the drain?

Oldmics
12-19-2005, 11:25 PM
Naw,Seriously try another refoam.

Sometimes the glue dries unevenly and pulls the coil to one side.

Just do it again and use the 30hz alignment while the adhesive is curing or cut the dust cap off and shim the coil while its drying.

Cheaper than the recone.Practice makes perfect.:banghead:

Oldmics

Neoman
12-20-2005, 12:05 AM
The Speaker Gods have Spoken


Thanks Oldmics!:D

toddalin
12-20-2005, 10:28 AM
Just did what I thought was necessary per OCS instructions push gently and listen for rubbing or scratching. Can I shoot myself now!:) I guess coil gap is pretty narrow? can you belive one out of the two 136's came out centered!

Guess I'm looking at recone? +shipping O.C.S:(

Better yet 40 bucks and 30hz sounds better or am I just blowing shipping down the drain?

No more 136As. OCS would redo it as a 2235 @ $174 + tax (similar but I don't know if it's exactly the same) and only in 8 ohm.

boputnam
12-20-2005, 11:46 AM
Naw,Seriously try another refoam.Exactly. Since the spider is still in-position, you're way ahead of the game. Run that 30Hz at about 1.5v drive, if you have a tone generator, during the entire drying. If using a CD player, just leave the gain at a soft "flutter" of the cone.

DO NOT LEAVE THE WORK AREA DURING DRYING, or you'll be sorry. Stay with it while it dries - especially in your case since you know from the recent try that this cone seems to want to skew... Use gentle pressure on the opposing side from that rubbing.

andresohc
12-20-2005, 06:47 PM
Bo, have you tried resurrounding using shims. I have done it both ways and have been successful both ways, but the OCS people strongly encouraged me to use the shimming method when they sold me the materials. I was able to go in back and watch some that were being repaired and I was able to pick up a bunch of different shims. Is there a measurable difference between the methods or just a matter of preference?
Exactly. Since the spider is still in-position, you're way ahead of the game. Run that 30Hz at about 1.5v drive, if you have a tone generator, during the entire drying. If using a CD player, just leave the gain at a soft "flutter" of the cone.

DO NOT LEAVE THE WORK AREA DURING DRYING, or you'll be sorry. Stay with it while it dries - especially in your case since you know from the recent try that this cone seems to want to skew... Use gentle pressure on the opposing side from that rubbing.

Neoman
12-20-2005, 09:29 PM
Thank you for the wisdom and knowledge. Hope to resurrect and keep the 136A drivers in their original condition.

Neoman

B&KMan
12-20-2005, 10:10 PM
Thank you for the wisdom and knowledge. Hope to resurect and keep the 136A drivers in their original condition.

Neoman


2 cents experience...

my brother is unfortunatly bad glued the dust cap and some partial edge is not proprely glued.... so ring at arround 150 Hz .....

many time is difficult to fixing with glue the dustcap because the link solder is exactly at same place to the edge of the dust cap so many molded preparation for perfect fix is necessary....


put tone and put your fing at arround a couple of place : maybe you find the bad section unglued....


:cheers:

boputnam
12-21-2005, 09:29 AM
Bo, have you tried resurrounding using shims. I have done it both ways and have been successful both ways, but the OCS people strongly encouraged me to use the shimming method when they sold me the materials. I was able to go in back and watch some that were being repaired and I was able to pick up a bunch of different shims. Is there a measurable difference between the methods or just a matter of preference?Hey, Andre...

I have, but I also try and avoid removing the dust cover unless there is other reason to. I just cannot get them repositioned cosmetically as perfect as Giskard does... I have run into one instance on one old frame (116H) where the shims were simply not effective - I had to remove and redo using the 30Hz tone. :dont-know