1966 Bulova Accutron Astronaut GMT Vintage Watch Review with Measurements
"The Accutron movement made its official appearance in October 1960. Designed as an electronic movement, the Accutron, designated the Caliber 214, utilizes a 360 Hz tuning fork and battery to replace the traditional balance wheel and spring. The Accutron movement was so precise and capable of handling extreme temperatures and pressure, that NASA utilized it in the instruments of the Gemini and Apollo cockpits. Chosen by the CIA for wear during missions with the A-12 and X-15 aircraft at the height of the Cold War, the Accutron Astronaut GMT has become a symbol of ingenious engineering and design, as well as a piece of aeronautic history."
Hodinkee has a great advertorial on the technology.
www.hodinkee.com
Specifications
1966 Bulova Accutron Astronaut GMT
Caliber 214 with rated 99.9977% accuracy; 360 Hz
Acrylic crystal
38mm case width
13.5mm case height
17mm lug width
Test Setup
A UMIK-1 pointed toward the watch. Windy and rainy day.
Given that the ambient noise is so high relative to the signal, the THD+N is impossible to interpret.
Objective Results
Using @JohnPM 's REW's RTA function, you can see that the tuning fork in the Accutron watch had a measured frequency of 360.01 Hz. It should be 360Hz.
Looking at the manufacturer's advertisements, it should offer 99.9977% accuracy...
I repeated the measurements again, and this time with shorter FFTs and this time, REW actually reported a measurement of 360.00 Hz.
In order for this 57-year-old watch to meet the advertised specification, it should not run faster than 360.008 Hz. Since REW rounds to two decimal points, it's very possible that this watch is continuing to meet its advertised performance. It is certainly safe to say that it is "at least 99.9972% accurate" which is only a maximum deviation of 0.0005% from the advertisement even though the real accuracy is likely better.
Next, I ran the watch through @pkane 's Multitone Analyzer. Here, I told the software to generate a 360 Hz tone so that it could assign a jitter value but no audio was being played. This is just the recording. The Multitone Analyzer software does not account for the UMIK-1's calibration but the range from 360 Hz to 1800Hz (for H2 and H3) is 0.177 dB to 0.003 dB of variance.
With 2M FFT and 128 averages, the rms-jitter was an impressive 6.1 microseconds. That's great for a 57-year-old watch!
Measuring it again with a smaller, less-precise FFT, and fewer averages, I was able to get a result showing "zero" measurable jitter.
Subjective Impressions
No firmware update was needed. I experienced no crashes or compatibility errors during my testing.
The Accutron was easily ABX'able against several mechanical watches in collection. The watch was free from any extraneous "ticks" or "tocks." Imaging was poor though the dispersion was superb as the 360 Hz tone was consistent on- and off- axis.
When assessed in a non-blinded fashion, my impression was that the second hand glided effortlessly without any of the jitter seen with mid-fi quartz watches, nor the "grain" one sees in the seconds hands of mechanical watches. There were no microphonics against the watch case which can be heard with many mechanical watches. In my opinion, the smoothness of the Accutron's seconds hand was equal to the performance of watches costing several times its price, including a $103,000 platinum Grand Seiko with a 9R02 Spring Drive.
Although "burn-in" is considered an audiophile myth, I am confident that the luminescent hands were brighter without being shrill after exposing the watch to bright light. The enhance visibility of the luminescent hands quickly faded though, potentially suggesting that I was adapting to the product or the burn-in would be better described as warm-up. Given the energy efficiency, I certainly recommend leaving it on all the time and keeping the watch exposed to bright light before relying on the luminescence.
Conclusion
Highly recommended. PRaT (Pace, rhythm, and timing) was beautiful. This watch easily performs as well or better than watches even 10 or 100 times its price. There are certainly better-measuring solid-state watches out there and certainly more musical mechanical watches for true audiophiles in search of luxury and exclusivity. Based upon my experience, however, the Accutron Caliber 214 certainly is worth an audition.
@amirm @LarryRS @rdenney @watchnerd @pseudoid
"The Accutron movement made its official appearance in October 1960. Designed as an electronic movement, the Accutron, designated the Caliber 214, utilizes a 360 Hz tuning fork and battery to replace the traditional balance wheel and spring. The Accutron movement was so precise and capable of handling extreme temperatures and pressure, that NASA utilized it in the instruments of the Gemini and Apollo cockpits. Chosen by the CIA for wear during missions with the A-12 and X-15 aircraft at the height of the Cold War, the Accutron Astronaut GMT has become a symbol of ingenious engineering and design, as well as a piece of aeronautic history."
Hodinkee has a great advertorial on the technology.
Reinventing Time: The Original Accutron
How a humming movement changed wristwatches forever.
Specifications
1966 Bulova Accutron Astronaut GMT
Caliber 214 with rated 99.9977% accuracy; 360 Hz
Acrylic crystal
38mm case width
13.5mm case height
17mm lug width
Test Setup
A UMIK-1 pointed toward the watch. Windy and rainy day.
Given that the ambient noise is so high relative to the signal, the THD+N is impossible to interpret.
Objective Results
Using @JohnPM 's REW's RTA function, you can see that the tuning fork in the Accutron watch had a measured frequency of 360.01 Hz. It should be 360Hz.
Looking at the manufacturer's advertisements, it should offer 99.9977% accuracy...
I repeated the measurements again, and this time with shorter FFTs and this time, REW actually reported a measurement of 360.00 Hz.
In order for this 57-year-old watch to meet the advertised specification, it should not run faster than 360.008 Hz. Since REW rounds to two decimal points, it's very possible that this watch is continuing to meet its advertised performance. It is certainly safe to say that it is "at least 99.9972% accurate" which is only a maximum deviation of 0.0005% from the advertisement even though the real accuracy is likely better.
Next, I ran the watch through @pkane 's Multitone Analyzer. Here, I told the software to generate a 360 Hz tone so that it could assign a jitter value but no audio was being played. This is just the recording. The Multitone Analyzer software does not account for the UMIK-1's calibration but the range from 360 Hz to 1800Hz (for H2 and H3) is 0.177 dB to 0.003 dB of variance.
With 2M FFT and 128 averages, the rms-jitter was an impressive 6.1 microseconds. That's great for a 57-year-old watch!
Measuring it again with a smaller, less-precise FFT, and fewer averages, I was able to get a result showing "zero" measurable jitter.
Subjective Impressions
No firmware update was needed. I experienced no crashes or compatibility errors during my testing.
The Accutron was easily ABX'able against several mechanical watches in collection. The watch was free from any extraneous "ticks" or "tocks." Imaging was poor though the dispersion was superb as the 360 Hz tone was consistent on- and off- axis.
When assessed in a non-blinded fashion, my impression was that the second hand glided effortlessly without any of the jitter seen with mid-fi quartz watches, nor the "grain" one sees in the seconds hands of mechanical watches. There were no microphonics against the watch case which can be heard with many mechanical watches. In my opinion, the smoothness of the Accutron's seconds hand was equal to the performance of watches costing several times its price, including a $103,000 platinum Grand Seiko with a 9R02 Spring Drive.
Although "burn-in" is considered an audiophile myth, I am confident that the luminescent hands were brighter without being shrill after exposing the watch to bright light. The enhance visibility of the luminescent hands quickly faded though, potentially suggesting that I was adapting to the product or the burn-in would be better described as warm-up. Given the energy efficiency, I certainly recommend leaving it on all the time and keeping the watch exposed to bright light before relying on the luminescence.
Conclusion
Highly recommended. PRaT (Pace, rhythm, and timing) was beautiful. This watch easily performs as well or better than watches even 10 or 100 times its price. There are certainly better-measuring solid-state watches out there and certainly more musical mechanical watches for true audiophiles in search of luxury and exclusivity. Based upon my experience, however, the Accutron Caliber 214 certainly is worth an audition.
@amirm @LarryRS @rdenney @watchnerd @pseudoid
