Polaris Memovox

The Polaris Memovox Q903847J is Jaeger-LeCoultre's reissue of the dive-alarm that made the Memovox name matter: 200 metres of water resistance paired with a mechanical alarm that rings at a preset time using a spinning disc rather than a striking train. The calibre 956 delivers both functions in a package collectors value for its rarity among complications, since a true mechanical alarm is a fundamentally different animal from a minute repeater or a chime. At 42mm in steel it wears large but not absurd, and the navy-dialled aesthetic tracks closely enough to the 1968 original that it reads as a coherent re-edition rather than a marketing exercise.

What it is

JLC introduced the modern Polaris Memovox as part of the Polaris line revival that began in 2018, reinterpreting a reference with roots in the 1959 Memovox Automatic and the 1968 Polaris dive-alarm. The Q903847J runs the calibre 956, a self-winding movement with a separately wound alarm spring and a rotating disc mechanism that produces the alarm sound when a hammer strikes the case at the set time. The 956 is a direct descendant of calibre 916 movements that established JLC's alarm reputation decades earlier.

JLC has offered the Polaris collection in several configurations since 2018 including a three-hand date variant and a world-time version; the Memovox sits at the top of the range within the steel Polaris family. Production is ongoing as of 2025, and no limited-edition caveats apply to the standard Q903847J.

Buying notes

Verify the alarm function works correctly at purchase: set it, let it ring, and confirm the tone is strong and consistent, since a weak or absent alarm can indicate a depleted alarm mainspring or a worn disc hammer. The 956 has two separate crowns, one for hands and one for the alarm; check that both operate with positive detents and no slop, as worn crown stems are a known wear point on alarm-complication movements. Inspect the case for crown-tube damage, particularly around the alarm crown at 4 o'clock, which sits in a vulnerable position on the case flank.

Water resistance should be confirmed with a pressure test before any aquatic use, especially on pre-owned examples where gasket service history is unknown. Confirm the reference number matches the specific configuration you want: the Q903847J is the navy-dial steel version and other Polaris Memovox variants carry different Q-numbers.

Market read

The Q903847J retails around $9,000 to $10,000 new depending on region and year of purchase, and the pre-owned market has generally held within 15 to 20 percent below retail for examples in good condition with box and papers. Premiums are modest because production is ongoing and supply is reasonably available through authorised dealers, though not always in stock. The alarm complication adds genuine collector appeal that the three-hand Polaris lacks, so the Memovox variants do command a consistent bump over base Polaris references of similar vintage in the secondary market.

Grey-market pricing has compressed somewhat since 2022, making this a better buy new or certified pre-owned than it was at peak market.

Service expectations

The calibre 956 requires servicing approximately every five to seven years; JLC quotes service costs in the $800 to $1,200 range depending on parts needed and whether the alarm mechanism requires disassembly and cleaning separately from the base movement. Independent watchmakers with JLC alarm experience can service the 956, but the spinning disc mechanism and dual mainspring architecture benefit from hands-on familiarity with the calibre family, so vetting your watchmaker matters. Budget more than you would for a simple automatic, since the alarm train adds meaningful labour time.