Tenor — identity sheet

Round 1 verdict — the geometry is wrong in all four. Rendered side by side they read as tents, and concept C reads as three mountains, which gives the fault away: the profile widens at a constant rate from crown to mouth, so it is a triangle with curved sides. A bell does not do that. Its crown is about 45% of the mouth diameter, the waist runs almost vertical for the top half, and the whole flare happens in the bottom third at the sound-bow, which is also the thickest metal in the casting. Concept D was right in kind — one contour, one counterform — so round 2 keeps D and rebuilds the profile.

Round 2 verdict — D2. The corrected section works: all three now read as a bell rather than a tent. D1 is handsome large but its counterform closes up by 24px and the three elements go spindly. D3 fails outright — the knocked-through centre line splits the silhouette and the thing reads as a table lamp, which is the risk of putting a drawing convention inside a mark instead of around it. D2 survives all three sizes and is the only one that still looks cast at 24px. Faults to fix in round 3: the crown domes too much and reads balloon-ish, the lip band sits under the bell like a separate plinth, and the headstock is a stub rather than a beam.

Round 3 verdict — none of them yet, and the fault is the lip. Seen at 160px the separate lip band reads as a plinth the bell is standing on rather than as the sound-bow, which is part of the casting and the thickest metal in it. All three share the fault because all three inherited the rectangle. 3b's void, moved out to the bow, stopped reading as a clapper and started reading as a bite taken out of the edge; 3c showed the beam is worth keeping, because without it the stem alone reads as a chimney. Round 4 rebuilds the profile so the flare runs to full mouth width and the lip face is a vertical continuation of it — one contour, no rectangle.