November 3, 2019

Modding a SMSL AD18 with Custom Rotary Knob and Power Switch

My newest toy is a S.M.S.L AD18 Desktop D-AMP with 80 Watts output. I have ordered this device directly from Aliexpress. The build quality is solid, solely the rotary encoder knob is a little flimsy. The other thing that annoyed me with the engineering is that the device uses over 1 Watt when turned off. In this post I show how I have resolved these two issues to mod the device to my liking.

Rotary Switch Knob

The default knob is made from black plastic. Since I had a knob made from anodized aluminium laying around from a previous project I wanted to swap the knobs. Then I also noticed that the rotary encoder itself was a bit low on quality. It had a lot of play in the rotary shaft. For this reason I decided to replace also the rotary encoder ensemby alongside the knob. That job was pretty straight forward.

  1. Open the front panel. Be aware, there are skrews under the glued down display glass. I opened the glass after heating up with a pair-dryer with a sharp knife.
  2. Note down the connections of the rotary switch to the little front display board using a multimeter.
  3. Remove the old rotary switch and replace with new one. Solder connections from rotary switch to front panel board.
  4. Test and reassamble the front plate.

Hardware Power Switch