4311 help and advice needed

[SUPERBEE]

My friend Cory who purchased my last set of 4311's some months ago called tonite to tell me the woofer on one makes a low rumbling like sound now at very bass'y passages. The settings are the same and this just started. Any ideas as to what could be causing this?

[Zilch]

Examine the cone for a flexural crease at the outermost concentric ring of the white part of the cone, ~5/8" in from where it meets the black accordian surround.

It's not supposed to flex there.

If that's the problem, a magnifier will reveal that the white Aquaplas is cracked along that line.

[SUPERBEE]

Zilch

THANK YOU!

Is this an age issue and what can be done about it?

Examine the cone for a flexural crease at the outermost concentric ring of the white part of the cone, ~5/8" in from where it meets the black accordian surround.

It's not supposed to flex there.

If that's the problem, a magnifier will reveal that the white Aquaplas is cracked along that line.

[Zilch]

If you confirm this is the problem, it's age and overexcursion: playing too loud with the bass boosted.

The remedy is a recone.

I'll try to get a pic tomorrow. There's one of a different unit in another thread here already:

http://audioheritage.org/vbulletin/s...65&#post123765

I'm not saying that's necessarily Cory's problem, but I've seen two recently like this, and it's easily verified via inspection.

L100/4311 woofers don't have a lot of failure modes....

[SUPERBEE]

OK.......This is weird.


Its not any kind of "crease" at all. What has happened is Cory has been rocking these so hard since he got them (And he RAVES about them almost every day to me) that the little wooden panel on the back where you wire the speaker up has worked itself loose and is vibrating at low bass passages and makes a "Farting noise"

So.....I guess we need to pull the woofer and get in the cabinet and re-glue that piece of wood back to the body of the speaker cabinet.

Anyone else ever heard of this?

[Zilch]

Thankfully, an easy fix, Bee!

I've never seen it, no, but I have found them easily removed when desired....

Edit: If it's of interest, I put up the second over-excursion example pic anyway:

http://audioheritage.org/vbulletin/s...740#post139740

[grumpy]

FWIW, I once repaired a terminal board on a 4311 that had come loose... there were
two small staples that held the piece of hardboard to the cabinet (as well as the glue).
I pulled the staples, scraped and sanded both surfaces, then reglued (gorilla glue and
some weight on the hardboard to hold it in place). Resprayed the back (touch up)
and put the terminals back in (they were a bit loose anyway). I don't expect it will
need the same repair again. Glad you found the problem and it was so simple

-grumpy

[SUPERBEE]

Thats the plan. Then I am going to blow his mind by playing my 4311's with the Scott tube gear. Lets see how fast he starts trolling for a new amp.