Seiko Caliber 5740C

The Seiko caliber 5740C is an evolution of the caliber 5740 and considered to be the grandfather of 36,000 bph hi-beat watch movements. This caliber is found in vintage Seiko Lord Marvel watches (ref: 5740-8000).

18,000 x 2 = 36,000

Worn & Wound explains this formula the best:

“Before the introduction of high-beat movements, the majority of watches operated at a frequency of 18,000 A/h, or 18,000 vibrations of the balance wheel per hour. In an attempt to improve accuracy, watch companies sought to create movements that beat at a higher frequency. Several Swiss brands set out to develop movements with a doubled rate of 36,000 A/h, and Girard Perregaux succeeded in bringing the first high-beat caliber to market in 1966.”

This blog paints a picture about beats:

“With 36000 bph, it means the movement in this watch “beats” 36,000 times per hour, or ticks 10 times per second (When this watch was made, Rolex’s best movement beat 19,800 times per hour or 5.5 times per second, and to this day their best tops out at 28,800 or 8 times per second). This provides for a sweeping second hand so smooth, it looks like an old fashion classroom electric wall clock and ticks so fast it sounds like a toy machine gun.”

Evolution of the Beat

The caliber 5740 (aka 5740A) was introduced in the early 1960s with a beat rate of 18,000 bph. Subsequently, the 5740B appeared on the market, upping the beat to 19,800 bph. By 1967, the caliber 5740C was introduced in the Seiko Lord Marvel model with a hi-beat rate of 36,000 bph. Note: not all Lord Marvels have the hi-beat movement, look for caliber 5740C.

Seiko Lord Marvel

horahalus.com calls the 36,000 Seiko Lord Marvel “a historically important watch” and makes the claim that:

“The 36,000 BPH Seiko Lord Marvel laid the foundations for what would eventually become the legendary Grand Seiko watches in the 70s till today.laid the foundations for what would eventually become the legendary Grand Seiko watches in the 70s till today.”

The most common question about the 5740C and Lord Marvel watch is: why didn’t Seiko launch their 36,000 hi-beat movement in the Grand Seiko or King Seiko lines instead of the Lord Marvel model?

The Lord Marvel powered by the caliber 5740C was produced from 1967 until 1975.

The caliber 5740C photo above was submitted by Frank who says:

“This movement is the Grand Daddy to all the Seiko Hi beat movements.”