Uploaded October 2025 | Updated September 2026, 7 hours ago

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Curious how loud the Flex Boss 21 runs? I put a dB meter on it and compared the noise to normal conversation while pushing ~6,000W of solar (the point where the fans kick on). The result: a low‑pitched whirr that’s below conversation level and not audible inside the house.

What I measured today:

Room noise (silence): ~28 dB (in this space)
Talking: ~mid‑40s to low‑50s dB
Flex Boss 21 fans at ~6,000W solar: lower than conversation, easy to talk over

Notes:

This is a real‑world test, not a lab spec. Different rooms and mic distances will vary.

I’ll revisit after inspection when I can add batteries/grid interconnect to load it harder and see how noise scales past 6kW.

If you want a deeper follow‑up (higher loads, different distances, or outside/inside tests), drop a comment.

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