Even though the JC-120 is still in production today, I’ve heard that it might not be possible to repair early generation JC-120s. Why is this?

On the JC-120, can I connect guitars to the Channel 1 and Channel 2 inputs simultaneously?

I’d like to connect an electric guitar to the JC-120 via an effect unit, and use the effect unit to create distortion. For the best sound, should I connect to Channel 1 or Channel 2?

What is the difference between the JC-120's two channels (Channel 1 and Channel 2)?

When moving the JC-120, I hear "splashy" sounds as if thin metal plates were being struck inside the amp. What causes this?

Do the early JC-120 amps have SEND/RETURN jacks like those provided on today's JC-120 models?