I have a Peavey Vypyr I use for practice and have an instructor who comes to my house. Is it possible to use 2 guitars into 1 amp? Would a Y-cable work and would this damage the amp?? Thanking you in advance.
If you have 2 inputs than it could work, I did it years ago with a buddy and his amp.
Its probly not the best idea tho
Your instructor should bring his/her own amp.
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my Peavey has a jack labeled "CD input" and it works, but it gives priority to the CD input, and of course no distortion/gain/other effects, so you'll have one really loud, really clean guitar, and another quiet guitar with effects, which will sound terrible, but will work.
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Quote by Sid McCall
Your instructor should bring his/her own amp.

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It won't sound good man. don't do it. Get your instructor to bring an acoustic if he can't bring a small amp.
whatever signal is louder at the moment, will be the one amplified (in a Y cable setup) so you will both sound muddy and awful if you play together
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Really you don't need an amp with guitar lessons. I never did anyway. Your teacher can play it through the amp and you can simply learn it without an amp. And then when he leaves you can use your amp and practice what you learn.