I have a question about musical notation. When changing the clef in the second ending following a repeat sign, should the clef be written in a smaller size?

GPT-5.4

Vote: No

The clef in a second ending after a repeat is a normal, functional clef change, not merely a cautionary reminder. Because it takes effect for the music that follows, it should normally be engraved at full size. Small clefs are typically used for courtesy or cautionary purposes, such as warning the player of an upcoming clef change at the end of a previous system. That is a different situation from an actual clef change at the point where the repeated passage proceeds into the second ending. So for the described case, the correct choice is "No": write the clef at normal size unless you are specifically adding a separate courtesy clef elsewhere.

Claude Opus 4.7

Vote: Yes

In standard music engraving practice, when a clef change occurs at a location that is a 'cautionary' or 'courtesy' clef—such as at the end of a system anticipating a change, or within repeat structures where the clef applies to a specific ending—it is conventionally written in a smaller size (typically about 75-80% of the normal clef size). A clef appearing in a second ending after a repeat functions similarly to a cautionary clef change, and engraving conventions (as codified by Gould, Ross, and others) call for the smaller size in such contexts.

Grok 4.20

Vote: Yes

In standard musical notation, a clef change that applies only to the second ending after a repeat sign is typically written in a smaller size. This convention signals that the alteration is local to the ending and does not affect the preceding or following sections. Using a full-size clef could mislead performers into thinking the change persists beyond the ending. Notation guides such as Behind Bars recommend the smaller clef for clarity in these specific cases.

Gemini 3.1 Pro

Vote: Yes

Yes. According to standard music engraving rules (such as those detailed in Elaine Gould's authoritative manual *Behind Bars*), any clef change that occurs within a system should be written in a smaller size (typically around two-thirds to three-quarters of the full size). While a clef change is generally placed *before* a standard barline, changing the clef at the start of a first or second ending is an exception: it must be placed immediately *after* the repeat barline. However, despite this unique placement after the barline, the clef is still occurring mid-system. Therefore, it continues to follow the rule for internal clef changes and must be drawn in a smaller size. The only time a full-sized clef is used is at the very beginning of a new system.

Final Summary

The AI Roundtable grappled with the fine details of music engraving, resulting in a 3-1 split. While Claude Opus 4.7, Gemini 3.1 Pro, and Grok 4.20 stood united in their defense of the 'smaller clef' rule, citing industry bibles like Elaine Gould’s *Behind Bars*, GPT-5.4 played the role of the lone traditionalist, arguing that a functional change deserves a full-sized seat at the table.

No agreement after 1 rounds of discussion. Final vote: No: 1, Yes: 3

Strongest Arguments

• Yes: Gemini 3.1 Pro provided a technical breakdown of engraving standards, noting that because the change occurs mid-system (even after a repeat barline), it follows the rule for internal clef changes and must be reduced to 66-75% of the standard size.
• No: GPT-5.4 argued that a clef in a second ending is a functional, permanent change for the music that follows, rather than a mere cautionary reminder, and thus should be engraved at full size to avoid being mistaken for a temporary courtesy.