Do the D'Addario EJ27-N Classic Rectified Nylon Trebles have the same tension and gauge as the trebles in the EJ45 Pro-Arté set, and can they be mixed without noticeable differences in tone or feel?

The D'Addario EJ27-N Classic Rectified Nylon Trebles are similar in gauge and tension to the trebles in the EJ45 Pro-Arté set, but they use rectified (precision-ground) nylon, which gives them a slightly different feel and a warmer, mellower tone. While you can mix them with EJ45 trebles, you might notice a subtle difference in tone and texture due to the rectified finish. If you want a completely uniform tone and feel, it’s best to use a matched set.

Are the EJ27-N Classic Rectified Nylon Trebles compatible with other D'Addario classical guitar bass sets, or do they work best only as a full EJ27-N set?

Yes, the EJ27-N Classic Rectified Nylon Trebles can be used with other D'Addario classical guitar bass sets. They are designed for compatibility and can be mixed with different D'Addario bass strings, not just the full EJ27-N set. This allows you to customize your string setup to your preference.