Beat rate, frequency, power reserve and lift angle for 29 common movements.
To read a watch acoustically, a timegrapher has to know how many beats an hour the movement is supposed to make. Feed it the wrong figure and it will confidently report a rate that is wildly wrong — assume 21,600 for a 28,800 bph movement and you will be told the watch is losing hours a day.
Most software can detect the beat rate automatically, and Chronograde's AUTO mode does. But detection is a guess from a noisy signal, and setting the figure yourself is always more reliable if you know the caliber.
| Beat rate | Frequency | Sound | In this list |
|---|---|---|---|
| 18,000 bph | 2.5 Hz | 5 ticks/sec | 2 of 29 |
| 21,600 bph | 3.0 Hz | 6 ticks/sec | 8 of 29 |
| 25,200 bph | 3.5 Hz | 7 ticks/sec | 3 of 29 |
| 28,800 bph | 4.0 Hz | 8 ticks/sec | 14 of 29 |
| 36,000 bph | 5.0 Hz | 10 ticks/sec | 2 of 29 |
Higher frequency generally means better resistance to positional error and shock, at the cost of more wear and a shorter power reserve — which is why 36,000 bph movements tend to advertise their reserve loudly.
Beat rate is authoritative. Power reserve is the manufacturer's figure for a healthy, fully wound movement — expect less from a watch that is due a service. Lift angle is the typical published figure used by timegrapher software to estimate amplitude, and is approximate; it is omitted where no standard figure is published, which is common for co-axial and some in-house escapements.
| Caliber | Beat rate | Frequency | Reserve | Lift angle |
|---|---|---|---|---|
| Grand Seiko 9SA5 Hi-Beat 36,000, 80-hour reserve. | 36,000 | 5.0 Hz | 80 h | — |
| Zenith El Primero Hi-Beat 36,000 automatic chronograph. | 36,000 | 5.0 Hz | 50 h | — |
| ETA 2801-2 / 2804 Hand-wound. | 28,800 | 4.0 Hz | 42 h | 50° |
| ETA 2824-2 The workhorse Swiss automatic. | 28,800 | 4.0 Hz | 38 h | 50° |
| ETA 2892-A2 Slim Swiss automatic. | 28,800 | 4.0 Hz | 42 h | 50° |
| ETA/Valjoux 7750 Automatic chronograph. | 28,800 | 4.0 Hz | 44 h | 47° |
| Grand Seiko 9S65 Automatic, 72-hour reserve. | 28,800 | 4.0 Hz | 72 h | — |
| Miyota 9015 Slim automatic. | 28,800 | 4.0 Hz | 42 h | 51° |
| Omega 1120 Based on ETA 2892. | 28,800 | 4.0 Hz | 44 h | 50° |
| Rolex 3135 Classic Datejust/Submariner caliber. | 28,800 | 4.0 Hz | 48 h | 50° |
| Rolex 3235 Chronergy escapement, 70-hour reserve. | 28,800 | 4.0 Hz | 70 h | 50° |
| Rolex 3285 GMT caliber, 70-hour reserve. | 28,800 | 4.0 Hz | 70 h | 50° |
| Sellita SW200-1 2824 equivalent. | 28,800 | 4.0 Hz | 38 h | 50° |
| Sellita SW300-1 2892 equivalent. | 28,800 | 4.0 Hz | 56 h | 50° |
| Sellita SW500 7750-type chronograph. | 28,800 | 4.0 Hz | 48 h | 47° |
| Tudor MT56xx (Kenissi) In-house, COSC-certified, 70-hour reserve. | 28,800 | 4.0 Hz | 70 h | 50° |
| Omega 8500 Co-Axial automatic (3.5 Hz). | 25,200 | 3.5 Hz | 60 h | — |
| Omega 8800 Co-Axial Master Chronometer. | 25,200 | 3.5 Hz | 55 h | — |
| Omega 8900 Co-Axial Master Chronometer. | 25,200 | 3.5 Hz | 60 h | — |
| ETA Powermatic 80 (C07) 80-hour reserve at 3 Hz. | 21,600 | 3.0 Hz | 80 h | 50° |
| Hamilton H-10 ETA C07-based, 80-hour reserve. | 21,600 | 3.0 Hz | 80 h | 50° |
| Miyota 8215 Automatic. | 21,600 | 3.0 Hz | 42 h | 51° |
| Omega 1861 Speedmaster hand-wound (Lemania). | 21,600 | 3.0 Hz | 48 h | 52° |
| Seiko 6R15 Automatic. | 21,600 | 3.0 Hz | 50 h | 53° |
| Seiko 6R35 70-hour automatic. | 21,600 | 3.0 Hz | 70 h | 53° |
| Seiko 7S26 Automatic (SKX era). | 21,600 | 3.0 Hz | 41 h | 53° |
| Seiko NH35 / 4R35-36 Seiko/TMI automatic. | 21,600 | 3.0 Hz | 41 h | 53° |
| ETA 6497 (Unitas) Large hand-wound, sub-seconds at 9. | 18,000 | 2.5 Hz | 46 h | 53° |
| ETA 6498 Large hand-wound, sub-seconds at 6. | 18,000 | 2.5 Hz | 46 h | 53° |
None of these figures is an accuracy specification. Two watches with the same caliber can run twenty seconds a day apart depending on regulation, service history, magnetism and how they are worn. The caliber tells you what the movement is capable of and what to set your timegrapher to — not how your watch is running. For that, measure it.
This table is the same reference data Chronograde ships, where entering a caliber fills these specs in automatically. See also COSC and METAS explained.