Connected MANAYO DM3 to microphone but not work.

Please turn on the 48v phantom power on your audio interface or mixers when using. The microphone amplifier itself has no power supply and must be provided with 48v power by the phantom power supply to work.

How to test whether it work?

DM3 provides the previously fixed 28db gain. After the connection is successful and the 48v phantom power is turned on, the signal amplification is extremely obvious. You can compare the input volume before and after connection.

What should I do if a lot of noise is generated after installing the DM3 mic preamp?

The DM3 mic preamp provides fixed 28db gain.It amplifies the signal but also the noise.thus, you will feel a lot of noise is added.In this case,Please turn down the gain on your audio interface then the the noise will be smaller or even disappear.

I used it on a kalaoke system but it not work.

Most systems provide 24v phantom power while DM3 must be used with 48v phantom power. In this case, please connect an external 48v phantom power supply to DM3 to solve this problem, an audio interface without phantom power can also be solved this way

Is DM3 suitable for condenser microphones?

No! It only works with dynamic and ribbon microphones. If you connect a condenser mic such as AT2020 which mentioned in the review, it won't damage any of your equipment because it has no power of its own, it just won't work.