Cube Audio FC8 speaker build help

Hello everyone,

I want to build this (plan below) bass reflex cabinet for the Cube Audio FC8 driver. This is my first attempt and I have some questions.

1. Are there any acoustic downsides to screwing the back panel in place so access to the interior can be maintained ?

2. There is a label on the side elevation drawing which says "This section might be filled with sand". What are the pros and cons of doing so, and what would be the process for filling / removing the sand ?

3. I have an oak floor which is laid on concrete. What sort of speaker feet would be best ?

Thanks in advance for any help,

Mark

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