Cheap Audio Ampflication for Piezo Buzzers: PAM8610 vs TPA3310 vs TDA2030

I decided to see how low you can get in costs for amplifiers suitable to drive a piezo buzzer sound installation. Basically you get all sort of digital amplifier ICs soldered on a small board with a basic circuit around. I am now comparing three boards, based on the PAM8610, TPA3310, TDA2030 chips. After I got a lot of background noise for the PAM8610, I figured that the amplification is actually too high, and compared to [the previous test](https://diode.zone/w/sDCg9GwVgHRBT6C7vQowE9), I no longer use a coil transform to match the impedance better with the piezos. With a direct connection, you no longer get background hissing, but you need to drive the amp higher with the line signal. I run all three at 12V, but the line levels are set differently to better match the capabilities of each board. That is to say, they are *not* equally powerful at full level. Here's a comparison of the three boards: - PAM8610 based: two channels, runs off 12V, has through holes for powering, left/right