L01 — K. 545, opening and changed return

Dossier index · prepared comparison, not yet auditioned · 16 September 2026

Question: How do two realizations make the relationship between I, bars 1–4 and 42–45 audible? Begin with timing, articulation and melody/accompaniment balance. Decide whether “return,” “surprise” or another description fits only after recording what was heard.

Release candidates

These are release identifiers, not session dates or confirmed identities of every streaming reissue. The comparison is ready for release-copy verification, not ready for published conclusions about two performances. No purchase or recording redistribution is required by this worksheet.

Session record to complete

Record listener, date, playback source/version, headphones or speakers, and any volume adjustment. Confirm the actual movement, full duration, repeat choices, and instrument/booklet credits where available. Keep unknown fields explicitly unknown. Use the NMA E02 score; if a performer edition is unknown, distinguish that from the score used by the analyst.

1. Hear the complete movement from each release once. If practical, hide performer names and biography on this first pass. A listener who already knows the context should record that fact.
2. Locate bars 1–4 and 42–45 in each performance. Record start/end times measured from the actual track, including silence at its start. Identify first statements versus repeats. Do not estimate times by proportional bar counts or album duration.
3. Compare attack spacing, duration at phrase endings, separation/connection of notes, and prominence of the left hand. Specify a difference only where it is audible; retain ambiguity and disagreement.
4. Revisit the complete movement so excerpts do not erase the preparation of the return. Add the listener’s description of the relationship, then revisit the historical context and record any change in interpretation.

Different instruments, performers, rooms and recording chains vary together here. This is a comparison of two realizations, not an experiment isolating the effect of fortepiano versus modern piano. An amplitude measurement would not by itself identify a performer’s intended dynamic or a listener’s feeling.

Exit: verified release copies, actual audition with passage timestamps and repeat information, specific observations, and at least one plausible alternative interpretation. Revise C14 and the essay only to the extent the resulting evidence warrants. Additional listeners can contribute disagreement; no consensus or human study is claimed by preparing this form.

Publication dependency — changed return and musical identity

The later companion essay scope depends on this comparison. No listening has yet been performed. The source-based first companion may proceed through author review independently; the second cannot make performance claims until the following are complete:

• Listener and session date recorded, with prior familiarity and playback conditions.
• Both actual release copies and K. 545 I tracks verified; substitutions/reissues disclosed.
• Each full movement heard before and after passage comparison.
• Bars 1–4 and 42–45 located in both tracks with measured elapsed start/end times and repeat/occurrence labels.
• Preparation and continuation around bar 42 heard and located, so isolated excerpts do not determine the argument.
• Timing, articulation and balance observations distinguished from notation and personal interpretation.
• Recognition, uncertainty and alternative responses recorded; “surprise” is not a required result.
• Instrument/edition unknowns and recording confounds retained.
• Each proposed essay claim mapped to the passage/session evidence below and checked against C14.

An actual listener’s record can support an attributed account, not a population-wide result. If an additional listener disagrees, preserve the disagreement. Do not backfill this form from a catalogue, score alone, or another writer’s listening description.