I upgraded the electrolytic caps for the tweeters in my Il 40's and what a difference, before there was low detail and rolled off and life less almost like a blanket was over the speaker, to me it was like I had earplugs in my ears, I couldn't listen to them anymore, I am use to my IRS Epsilons tweeter so I know what a good tweeter sounds like but after the cap mod oh boy I'm liking the il 40's and can listen to them now for hours on end, the caps I used was the Jantzen Alumen Z-Cap, it takes a few hundred hours to fully break in but when it does it's sound is addictive, they are huge but can be installed, here is a video I made of how I installed them and a review on the caps
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