fine mesh in horn throat?

[frank23]

hi,

I have a pair of 2420 drivers where I can see into the horn throat. I also have a pair of 2425 drivers where the horn throat is covered by a perforated mesh. This is the same as with a pair of 2416.

Now I came upon an item of a new 2426 on ebay that carries a sticker that covers the horn throat that says "pull, to remove perforated center before installing horn".

Does this mean, the horn throats of the 2425, 2426 and 2416 are meant to be open like the old 2420's?

for pics see this ebay item:

http://cgi.ebay.nl/ws/eBayISAPI.dll?...779386862&rd=1

Greetings, Frank

[Mr. Widget]

The screen is to prevent bugs and other debris from entering your driver... not a bad idea. Many older drivers do not have these screens, most new drivers do. Some audio tweaks (you know who you are) carefully remove the screen so as to have even less between their music and themselves. Personally I'd rather not risk getting debris in my driver.

Now, the "pull" sticker is something else entirely. That is on the gasket. A brand new driver will have that, and so will one that has a new gasket. You must pull out that center plug or the sound will not come out of the driver very well... it will be blocked by the donut hole of gasket material.

Widget

[frank23]

thanks! now I understand.

and since I am "one of those" I think I am going to remove the anti-bug mesh

I use mine only indoors in a home environment, in the years I've used the 2420 I never saw a bug in my phaseplug, so I'll take the chance with the 2416's

greetings, Frank

[Mike Caldwell]

Hello
The 2420, 2416, 2421 and the older LE series series
drivers do have a fine mesh screen deep in the throat directly
in front of the phase plug, maybe some one removed it on the
drivers you had looked into. All of the newer 2425 and the current 2426
drivers have the screen at the front edge of the throat at the
mounting flange.

Mike Caldwell

[johnaec]

How do you remove those screens? 'Careful cutting with an X-Acto knife? I sure wouldn't want to try that, especially on a new driver...

John

[Maron Horonzakz]

By removing the screen you,r taking the chance of getting iron paticles down in the voice coil gap. You,d be suprised at what floats around in your home. I recommend not removing the screen. Sonicley your not going to hear any improvement. But over time without the screen you,l have problems.

[Alex Lancaster]

I think Maron is a 100% right, in 25+ years I have not done an A/B test, as I use them, get rid of them, and go on, but I do not recall a sonic diff.; Maybe some guys here have?

[Jakob]

Hi!

I have the mesh in my 2441's, and over the years quite a lot of debris have come to rest along the edge. How do You get rid of this?
I was thinking compressed air, but maybe you then push some of the debris inside the driver? Any tips?

Regards: Jakob

[stevem]

I think Maron is a 100% right, in 25+ years I have not done an A/B test, as I use them, get rid of them, and go on, but I do not recall a sonic diff.; Maybe some guys here have?

At the risk of being labeled a "tweak", I have removed the screens and do hear a slight difference. A little less "hash" if you will. Of course YMMV.

[Mike Caldwell]

Hello
I would use a vacume to suck the dirt and dust away, like you said
using compressed air could blow the dirt on into the phase plug and
then work it's way to the voice coil. You would want to reduce a normal
vacume cleaners hose down to a half of an inch or less in diameter to be
able to reach in and easly go around the edges of the screen. You could remove the diaphragm and then use compressed air blowing it through the slits in the phase plug. You would want to clean out the voice coil gap if you did it that way.

Mike Caldwell

[Mr. Widget]

I wouldn't use a vacuum... you'd be surprised at the power of a vacuum... I once tried to make a dust collection system for my shop on the cheap and used a galvanized steel trash can as a collection tank... when the hose got clogged with debris, the power of the vacuum collapsed the steel can in about a second.

I have done as you described using compressed air. Remove the diaphragm and blow the air through the phase plug and the debris will come flying out the throat.

If you are not equipped to remove and replace your diaphragm, you can use bits of aggressive double faced tape on the end of a dowel. Gently pressing it against the screen to stick the debris on to the tape.


Widget

[Mike Caldwell]

Hello
That's why I suggested reducing the vacuum hose down very small, to avoid sealing the throat completly with the hose and turning the diaphragm into a piece of wrinkled tin foil.

Mike Caldwell

[Zilch]

Buy the mini-accessory kit available at your vacuum store. It has a neat little brush extension that reaches right in there. The suction is adjustable. Several forum members use it for throats and screens routinely:

http://store.yahoo.com/eurekaservice/minitoolset.html

Does LE85's quite nicely, for example.

See also: http://audioheritage.org/vbulletin/s...ment#post50197

Removes dome dents, too!

[John]

I will back Widget up on the sticky tape method, works great. And when it looks clean use a few cotton swabs dipped in thinner and the screens will look like new.

[sonofagun]

Might I suggest a small "plug" of the acoustically transparent open cell foam which I sell? I'll send you all you should need for multiple horns for $5 (and up) depending on your location and amount needed (recommend 1/2", 3/4", or 1" thick please specify) - you can cut to fit using scissors. It will keep debris, bugs, etc. from entering into the horns internals and could be easily removed or replaced at will.

Alternately I can provide a sheet of 1/4" or other thickness foam which you can cut to cover the entire mouth of the horn.