【Alvin - A Coffee E-commerce Founder Passionate About Sharing】
The speaker in the video is Alvin, founder of the coffee e-commerce brand Caffeine Stone.
He is also active on YouTube and Instagram, where he shares coffee knowledge, brewing techniques, and equipment insights. He has earned a strong following among coffee enthusiasts.
Drawing from his professional understanding of coffee, Alvin helps users learn how to operate a wide range of coffee equipment.
Through real testing and personal experience, he provides buying advice to help people find the tools that best suit their needs.
【Cordless Operation for Flexible Grinding Scenarios】
Alvin shares that the main difference between the A4 and A5 electric grinders is their burr size and burr geometry design. The A4 is equipped with 48mm burrs, while the A5 features 53mm burrs.
Both grinders are powered by 18650 lithium batteries, the same type used in electric vehicles. These batteries offer strong endurance.
A full charge supports approximately 30 to 50 grinding sessions[1]. Both grinders also include an automatic stop function that shuts off the motor once grinding is complete[2], helping conserve battery power.
Based on Alvin’s experience, A4 and A5 grinders typically only need to be charged once per week.
While he mentions that their weight may not be the most portable option for camping[3], their cordless operation solves the problem of needing power outlets. This allows for greater flexibility in choosing where to grind coffee.
Frank
Femobook's Editor
2. This video shows the previous version of the "Auto Stop After Grinding" feature, where the system automatically determined when to stop based on the grinding process.
Taking into account that areas with significant weather fluctuations—such as large changes in temperature and humidity—could occasionally lead to slightly early or delayed stops, the updated version now uses a "Timed Auto Stop" mechanism that is less affected by environmental factors.
3. The A4 and A5 grinders weigh 2.6 kg each. For those who enjoy car camping, they make excellent companions for enjoying high-quality coffee outdoors.
【Alvin’s Overall Review】
A4: Clean Pour-Over, Bright Espresso, and Reliable Performance
Alvin thinks that the A4 electric grinder performs well in pour-over brewing, producing clean, delicate flavors that are easy to enjoy.
For espresso, it brings out bright acidity, making it ideal for those who appreciate more vibrant, acidic flavor profiles.
Although Alvin observed that the A4 has a slight drop in RPM and some motor noise sound during espresso grinding[1], he emphasizes that this did not negatively affect the overall grind quality.
He still considers the A4 to be a grinder that performs impressively in both consistency and flavor clarity.
Frank
Femobook's Editor
A5: Rich Aroma and Complex Flavor Beyond Expectations
According to Alvin, the A5 electric grinder delivers an impressive flavor performance for pour-over coffee. The cup shows rich sweetness and aroma, with a smooth, well-rounded mouthfeel.
He describes the overall flavor balance as harmonious and says the grinding performance exceeded his expectations.
When grinding for espresso, the A5 excels in expressing flavor depth and nuance.
Alvin specifically mentions that using medium to dark roasted beans allows the A5 to release bolder aromas and layered complexity. He believes this leads to an even more enjoyable flavor experience.
In conclusion, Alvin states that the performance of both the A4 and A5 electric grinders truly impressed him.
They reshaped his expectations for grinders in this price range. He emphasizes that it is hard to find comparable products at this level that can compete with their performance.
Note: The content above is excerpted from the YouTube video by《Caffeine Stone》.
The Femobook A2 is a compact, battery-powered coffee grinder built with portability in mind. In this hands-on revi...
