ZA3/V3/BT20A PRO with low volume, the amp need to be almost at full volume to output normal volume.

• The ZA3/V3/BT20A PRO amplifier is equipped with a built-in logarithmic taper A Potentiometer (Pot). This design feature makes the volume control more responsive at higher volume levels, as shown in the image below. Ensure that the audio source's volume is set at 50% or higher, and adjust the ZA3/V3/BT20A PRO's volume to max.
• P.S.: You could also add a preamp for further enhancement.
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