The stock Eminence PRO 5W8 (ferrite magnet) was quite a disappointment.

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As a result, I wouldn’t use them in their current form, and decided to modify them

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The first step was to remove the dust cap.

• Worse result overall with less bass output

• Break-up in frequency was still there

• Loss of maybe 0.5 dB in overall efficiency

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Second step was a phase plug

• Better than one, but still worse than stock.

• Sometimes you win, sometimes you lose.

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Third step was dope coating the cone.

• Three coats were added.

• Not a significant measured improvement

• Break-up is still there and strong

• Distortion somehow is a tad higher

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Fourth step was adding a bigger dust cap

• Felt was added inside the voice coil cavity to fill the air space and hopefully damp any resonance there.

• 58 mm dust cap were used.

• Dope added on dust cap. (two coats)

• FS lowered, which was welcomed.