Applying Aquaplas coating to a JBL diaphragm.

The JBL titanium diaphragms are extremely tough...at the expense of some harsh, "edgy" sounding resonances due to the thinness of the dome. Some will say the titanium "cut's through the mix". It's actually distortion. JBL decided to coat the diaphragm with Aquaplas on the "SL" models such as the 2450SL and 2451SL to tame the resonances and clean up the sound quite a bit. JBL also coated the beryllium diaphragms in the Everest II, as well as the 2435 drivers in the VerTec Line Array Systems, and the tweeters in the LSR Studio Monitors. The mantra that was coined by Greg Timbers is, "if it's metal, coat it". It's pretty tedious...and it works. This is the identical material that JBL uses on compression driver diaphragms and all other drivers that feature Aquaplas. I also use it to blueprint the moving mass of my True Reproduction Recone kits that call for Aquaplas. Please review my other videos for examples of what I can do. I welcome your inquiries.
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[@samuelsalins8309]

Good job 👍

[@moodyga40]

was the first sweet in the mid band sounded like it

[@edgewound]

Sounded like what? I think you might be hearing some artifacts from either my phone's camera mic or some crackling from my sweep generator. At the test voltage of 1 watt, the SPL is about 110+dB, so the mic is getting a bit stressed and the compressor/limiter is kicking in.

[@laniroli3714]

You'r changing it's caracteristics. You want to avoid those harsh midds, go for metalic horn, damped with bitum. It will calm those harsh midds & have better highs at 12khz

[@edgewound]

You're correct. The characteristics of the harsh secondary harmonics are greatly reduced by the damping of the Aquaplas.

[@carlosmante]

where is "Aquaplas" available?

[@alexw890]

How did you apply the aquaplas?

[@edgewound]

Very carefully. Measured for before and after moving mass. Apply...allow to dry...weigh for added mass. It's a pretty delicate proprietary process.

[@oohms88]

It looks like it is applied much thicker than the SL diaphragms

[@edgewound]

I also apply it to the suspension. Less than a gram of added mass. I blew compressed air to redistribute some of the Aquaplas, so it gave the wavy, textured impression.

[@obiessen]

nevercoat the surround Fs will go up pulse will go down! qms will change and so on.

[@edgewound]

Please tell me the Fs of the JBL 2445H/J.

[@obiessen]

data are on internet around 460 HZ@@edgewound why you need to know?

[@edgewound]

@@obiessen JBL, nor any other manufacturer of compression drivers publish Thiele-Small parameters. I'm curious from where your data come. BTW...Meyer Sound dampened the metal surrounds of JBL diaphragms with a coating to dampen resonances...distortion.

[@obiessen]

@@edgewound messurements, he will have the same problems .all parameters change,

[@obiessen]

@@edgewound check imp curve you wil see

[@robertozanetti7707]

I think you have made inadequate a diphragm .........................

[@edgewound]

You are free to think what you will. The response is improved. Secondary resonances damped.