extending wire with a bigger one(IS IT SAFE?)

[Ali-Ghost]

Hey guys I got an old MHC RG440 ,its wire got cut out so I replaced the missing wire with one I had in my store room, so I just wanted to ask that should I do it or should I not, please help me guys.
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[Ali-Ghost]

Sry guys I'm such an idiot turns out sound can't fkin travel through some bigger tunnel, nevermind