288-16k removing screen

[Barossi]

Hi,
i would like to remove the metallic screen of my 288-16k driver.
Is there anything i should pay attention to?

Is it neccesary to remove the screen?
It should improve the HF response...

Greetings Barossi

[Barossi]

Hi,

nobody??

Greetings Barossi

[RonSSS]

Where is the screen in the 288-K?
If it's right at the gasket interface, it's easy.
If it's in the throat, you will have to break it ian pull it out with needle nose pliers.

I have done this on the small format drivers, and to my ears anyway, the sound is much better. HF is extended.

Others will likely disagree.

Ron

[vuki]

True-the sound is better without screens.

[bfish]

I don't have the answer, but I hate to see a member left hanging (hmmm, maybe I should rephrase that....)

My logic says leave 'em alone, because;

All Altec HF drivers have them, not just the ones likely to be used outdoors.
All published performance data was taken with screens in place.
Since wavelength shortens with rising frequency, the claims of extended response when screens are removed don't hold water. If the screens were attenuating the output, the low end of response would be affected, not the high.
Removal is permanent.

Until I see test data proving otherwise, my screens will stay where Altec put them. I fail to see the logic behind most so-called improvements to classic gear that was designed by folks with far more knowledge than most of us, and after doing extensive research instead of fleeting speculation.

The devices we consider classics became so because they excelled, not because they needed to be improved.

Bet you'll get some responses now.......

[bfish]

For anyone willing to do the math;

Transparency Index (TI) given by the following formula:

TI = nd2/ta2 = 0.04 P/1rta2

where:

n = number of perforations per sq in;
d = perforation diameter (in);
t = sheet thickness (in);
a = shortest distance between holes (in);
a = b - d, where b = on-center hole spacing (in);
p = percent (not fractional) open area of sheet.

The formula is valid for either straight or staggered perforations. An approximation for the value of a, when you do not know the value of b, is:

a = d[(const./P1/2) -1]

The value of the constant is 9.5 for staggered and 8.9 for straight perforations.

Further analysis continues at;

http://www.iperf.org/ac14.htm

[Tom Brennan]

I've had many Altec and JBL compression drivers, some with screens and some without and I'm damned if I ever heard a difference I'd attribute to removed bugscreens.

Same thing goes for Alnico and ferrite.

[Steve Mac]

I don't believe they sound worse without them.
The only reason they put them in there was to
prevent "bugs" from getting in there. They didn't call em "attenuator" screens. I had this conversation with GPA and they had no issue with their removal at all. I have seen some of these screens that are extremely corroded or dirtied up...whatever the correct phrase is and in that case you would be wise to remove them. But if you do, be vigilant to the fact that things are free to crawl or float in there..just my 2 cents...