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Figure 17: Cal. 2600A back © Omega SA
In 1998, the first modification of the caliber 1170 was made. To eliminate the rotor noise, the platinum weight was no longer mounted into the caseback but was attached to the backside of the movement employing a slide bearing with two jewels. This new movement was designated the Cal. 2600A and only twenty were produced from 1998 to 2002.
[PuristS’ Trivia] A variety of engraving patterns on the Cal.2600A tourbillon base without standardization were used.
Figure 18: Cal. 2600B © Omega SA
In 2002, a major facelift was done and Omega began to expand its ‘Haut de Gamme’ department. Designated caliber 2600B, Omega incorporated a new tourbillon cage and recalculated the Phillips overcoil in the Breguet hairspring used in the escapement. The monopiece index was replaced by a double-piece index and the ‘Omega’ sign of the cage was adapted. The movements are assembled and regulated by Omega and then sent to COSC Bienne for the chronometer tests. A new dial design gave an updated look and the hand engraved pattern on the tourbillon base was standardized as a sunburst pattern. A bridge replaced the retaining plate of the intermediate wheel.
[PuristS Trivia] Due to its special shape, this bridge is called ‘Penguin’ within the “Haut de Gamme” department.
Cal. 2600B is still in production today (April 2007).
