First look: Bengle's pump sound
Decent Engineer Ben Champion, normally living in Australia, is here in Hong Kong for our first DeCon event. We just received Bengle firmware from Ray that powers everything up, and allows us to make an espresso. Ray and his assistant Myles are flying in today.
This video lets you hear what the totally new pump control sounds like. What's different? On Bengle, the pumps are operating at a fixed 120hz frequency, and the piston stroke length is being controlled to affect flow. On the DE1, each piston stroke is full power, and we change the frequency.
You'll notice that not only does the pump sound completely different, but also that it's much quieter. That's because the pistons are not banging against the start and end of each stroke.
I used a decibel meter on my phone to measure the volume level. The room ambience was around 60db. With the phone about 20cm from the espresso machine, the pump sound peaked at 70db, while being at 65db most of the time. If you use headphones, you'll be able to hear background sounds, such as water splashing into the milk jug, as a comparison to the pump sound levels.
You might notice that the temperature line is not accurate in the video. That's because temperature control is not yet enabled in this firmware version. We'll be doing that tomorrow when Ray and Myles are here.
Updated 2025/02/27