I still haven't decided if I want to go the veneer ply or just veneer the cabinet once it's complete. Mitering the edges will be a pain since I haven't done it before I think I'd waste wood and time. Rabbit or butt joints are what I'll end up doing if I don't go the veneer ply route. This is the first time I've built speakers so KISS is key. The less complicated the better.
I'm not advocating mitered edges over butt joints, or the other way either. There are trade-offs which ever way you do it. Just so you know in advance.
Butt joints may be simpler to perform, but when you finish the cabinet, the exposed wood edges must be sealed. Unsealed wood edges will show through double layer veneer or numerous layers of paint. It's called "telegraphing".
One certain way to avoid telegraphing is to use mitered joints. Another way is to "paint" the exposed edges with at least two coatings of a 50/50 mix of wood glue and water. And yes, you should sand in between coats.
Either way you do it, it will be more work than you originally thought if you want it to look good
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