Does changing from D'Addario EZ920 to EJ16 strings require a re-setup of the acoustic guitar?

Switching from D'Addario EZ920 to EJ16 strings typically does not require a full guitar re-setup because their gauges are very close. However, slight adjustments in action or intonation might be beneficial for optimal performance but are not strictly necessary.

What is the difference between D'Addario EJ16 and EXP16 acoustic guitar strings?

The difference between D'Addario EJ16 and EXP16 strings is that EJ16 are uncoated phosphor bronze strings, offering a bright and clear tone but with a shorter lifespan. EXP16 are coated phosphor bronze strings, which last longer and resist corrosion while maintaining a similar tone, but with a slightly smoother feel and less squeak.

Can I use D'Addario EJ16 0.012 gauge strings on a Yamaha F280 guitar without bending the neck? Is it safe?

Yes, you can use D'Addario EJ16 0.012 gauge strings on a Yamaha F280 guitar safely. These light gauge strings should not bend the neck, especially if your guitar is set up properly. It's always good to monitor neck relief after string changes, but EJ16 strings are commonly used on guitars like the Yamaha F280 without issues.