Hacker News Reader

That is of course not true. dB without reference is perfectly fine to use for gain and attenuation. dBm or any of the variants would be flat out wrong.

View on HN

Even then, you'll get different results if it's 10 dB of voltage gain or 10 dB of power gain. You need to know what the actual units are.

No, dB are always power gain.

Exactly, and that's why a voltage gain of factor 10 is 20dB, because it's a power gain of factor 100.

Reply on news.ycombinator.com