Grand Seiko Snow Blue Tentagraph SLGC007 Watch Review
The Grand Seiko Snow Blue Tentagraph SLGC007 Hi-Beat Automatic Chronograph was unveiled at Watches & Wonders 2025. Save for its dial, it shares much in common with the inaugural Tentagraph SLGC001, unveiled two years earlier. Ordinarily, an additional dial colour doesn’t warrant discussion, but when it comes to Grand Seiko, Angus Davies finds it difficult to look away.
Image – Grand Seiko Snow Blue Tentagraph SLGC007
Grand Seiko fandom
When I was younger, I had more money and less sense. Despite having two children, I spent a significant chunk of my savings acquiring a brand new Porsche 911. The children’s growing limbs were bent to fit as I squeezed them in the rear seats, employing my best origami skills. And despite a few protests emanating from the rear of the cabin, everything was fabulous behind the wheel. The flat six sounded as sonorous as a tenor performing at La Scala and the car hugged the blacktop with aplomb. Eventually, sense prevailed and my driveway played host to a series of large saloons, estate cars and the odd gas-guzzling SUV. However, the 911 days will forever remain etched in my memory.
Image – Grand Seiko Snow Blue Tentagraph SLGC007
Today, the children have flown the nest. It’s just me, my wife and Oscar, our faithful cocker spaniel. Despite all the years that have passed since owning my Swabian thoroughbred, I’ve never lost my affection for the 911 nor my desire to own another. Whenever I hear the distinctive soundtrack of a Porsche engine, I turn, stare and beam with delight. Once you’ve owned a 911, you will forever remain a fan.
The reason for my automotive prelude is that Grand Seiko ownership has affected me in exactly the same way. Despite my chosen profession, I no longer possess many watches; however, I do own two GS models, both Spring Drive references. Once you’ve experienced the sweet taste of Grand Seiko ownership, it’s difficult not to crave another GS-branded beauty. Moreover, unlike said 911, Grand Seiko ownership necessitates few concessions to practicality.
Grand Seiko Hi-Beat movement
The hi-beat (5Hz) movement is a speciality of the house. Few brands offer movements with a cadence of more than 4 Hz, because high-frequency movements consume more energy due to the fast pace of the regulating organ, escape wheel, pallet lever, etc. Ultimately, this characteristic can result in a watch having a rather paltry power reserve. Another potential problem with high-frequency movements is that they tend to consume greater amounts of lubricant, which can ultimately exacerbate wear. At this juncture, some horophiles may have grabbed their coat and started heading for the door; however, I urge them not to cross the threshold. Grand Seiko, having surmounted said issues, has been delighting watch aficionados ever since it unveiled the inaugural high-beat movement, the Calibre 9S85, in 2009.
Image – Grand Seiko Calibre 9SC5
What makes the Calibre 9S85 movement so special? To start with, the escape wheel and pallet lever are formed using MEMS (Micro Electro Mechanical System), a lithographic process where highly-precise parts are effectively grown. The pallet lever is openworked, reducing mass and thereby mitigating energy consumption. The teeth of the escape wheel incorporate small reservoirs that retain lubricants, reducing wear.
At this point, you may wonder why Grand Seiko has expended much effort developing its high-frequency movements. Primarily, a high-beat movement (5Hz) is more precise, especially when affixed to the wrist. This is because when the watch is worn, the rate is less prone to positional influence. Furthermore, a high-beat movement (36,000 vph or 10 beats per second) proffers superior shock resistance, again aiding precision.
Grand Seiko Calibre 9SA5
Since it was founded in 1960, Grand Seiko has been unwavering in its pursuit of continuous improvement. In 2020, to coincide with its 60th anniversary, the brand unveiled a limited edition watch (part of the Evolution 9 collection), the SLGH002, equipped with a new automatic movement, the Calibre 9SA5. This movement also had a cadence of 5Hz, but incorporated some additional details destined to make it even more appealing to horological connoisseurs.
Image – Grand Seiko Calibre 9SC5
Firstly, the Calibre 9SA5 is endued with a dual impulse escapement. Most mechanical watches feature a Swiss lever escapement which is a tried and tested approach to controlling the flow of time. It proves relatively simple to assemble, making it ideal for mass produced watches. However, the Swiss lever escapement serves the balance with an indirect impulse which is not very efficient. Indeed, there is a significant loss of energy between the pallet lever and escape wheel due to friction. With Grand Seiko’s dual impulse escapement, the balance receives an indirect impulse (like a Swiss lever escapement) when the balance wheel rotates in one direction, but it then receives a direct impulse when rotating in the opposite direction. A benefit of using the dual impulse escapement is that it significantly improves the power reserve.
Secondly, Grand Seiko went further by equipping the watch with a free-sprung balance and endowing the balance spring with an overcoil. This winning combination serves to enhance isochronism and further mitigate any positional influences on the rate.
Grand Seiko Calibre 9SC5
In 2023, Grand Seiko unveiled the Tentagraph SLGC001, a chronograph incorporating a new hi-beat movement, the Calibre 9SC5. Like the Calibre 9SA5, it features MEMS technology, a dual-impulse escapement, a free-sprung balance and an overcoil. However, as this is a chronograph, the Japanese marque also incorporated a column-wheel and vertical coupling. This latter pairing, much loved by watch aficionados, delivers stutter-free actuation of the chronograph and imbues the pushers with a smile-inducing smoothness. Lastly, to further heighten desirability, the movement features two barrels, delivering a power-reserve of 72 hours.
Image – Grand Seiko Calibre 9SC5
Grand Seiko Snow Blue Tentagraph SLGC007 – Watches & Wonders 2025
This year at Watches & Wonders, Grand Seiko released several ‘novelties’, including the Grand Seiko Snow Blue Tentagraph SLGC007. This reference is almost identical to the aforementioned Tentagraph SLGC001. The case is formed of the same high-intensity titanium and measures the same 43.2 mm in diameter. It also features the same high-intensity titanium bracelet and, most pertinently, it’s fitted with the same impressive movement, the Calibre 9SC5. However, the dial of the Grand Seiko Snow Blue Tentagraph SLGC007 differs from its forebears and delivers a high quotient of newness, pairing the brand’s beloved Mount Iwate dial pattern with a bewitching pale blue hue.
Image – Grand Seiko Snow Blue Tentagraph SLGC007
Mount Iwate dial pattern
In 2006, Grand Seiko released its first mechanical watch featuring a 72 hour power-reserve, the SBGL001. This model was equipped with a distinctive ‘Mount Iwate’ dial, named after the mountain overlooking the Grand Seiko Studio Shizukuishi. It is within this building, nestling within a quiet forest, where the Japanese marque crafts its multi-award-winning mechanical watches.
Image – Grand Seiko Snow Blue Tentagraph SLGC007
Grand Seiko Snow Blue Tentagraph SLGC007 – dial
Ordinarily, an additional dial colour would not motivate me to write numerous column inches; however, few brands create nature-inspired dials quite as well as Grand Seiko. Inspired by the ‘rocky ridges and majestic deep snow of Shizukuishi’, the dial on this occasion is dressed in a shade of pale silvery-blue. It exudes freshness, reminiscent of walking on snow-clad ground. On seeing the watch for the first time at Watches & Wonders, it almost took my breath away. Three recessed counters, each adorned with a snailed finish, punctuate the wintry scene.
Image – Grand Seiko Snow Blue Tentagraph SLGC007
Beyond the beauty of the stunning dialscape, Grand Seiko has enriched the vista with luminescent hands and indexes and topped off the scene with a box-shaped sapphire crystal that drinks in ambient light, bathing the indications with notable brilliance. Throughout the dial, light and shadow sit in close proximity, a reciprocal relationship that’s repeated on the case and bracelet.
Grand Seiko Snow Blue Tentagraph SLGC007 – closing remarks
Image – Grand Seiko Tentagraph SLGC001 (unveiled in 2023)
The new Grand Seiko Snow Blue Tentagraph SLGC007 doesn’t supersede the Tentagraph SLGC001 (unveiled in 2023), it merely serves to offer consumers extra choice. Don’t think of it as a new generation Tentagraph, just a new colourway to tempt you away from mediocrity, a bit like the horological equivalent of the 911.
Further reading
https://www.grandseikoboutique.uk/
Technical specifications
- Model: Grand Seiko Snow Blue Tentagraph SLGC007
- Case: high-intensity titanium, diameter 43.2 mm, height 15.3 mm, water resistance 10ATM (100 metres), box-shaped sapphire crystal to front, sapphire caseback.
- Functions: hours, minutes, small seconds, date, chronograph
- Movement: Caliber 9SC5, Self-winding movement, frequency 36,000 vph (5 Hz), 60 jewels, power reserve 72 hours.
- Bracelet: high-intensity titanium bracelet with 3-fold clasp with push button release.
- Price: £12,850 (RRP as of 13.8.2025)