Second theme is, that I do not want PUS coverings, similar to the project of wazkelly https://goo.gl/KSY9W9
I want to use some Aluminium bolt, to fill the lower niches under the PUS, to drill proper and stabile holes for the screws, using the springs betweet the PUS and the Aluminium to keep it adjustable. So my question is, if the Aluminium could have some effect on the sound, did someone had experience with that? For it is not magnetic, but maybe could still have some negative impact?

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