Squash balls have proven to be excellent for decoupling your printer from your table, thus reducing vibrations/noise.

I had done a similar mod on my former PRUSA MK3 and it was a huge improvement.

On the BL A1, the stock feet are pretty good, but these squash ball feet will still improve vibration/noise, although not as much as on the MK3.

Be aware that your printer will be more wobbly, but that doesn't affect print quality.

I don't use the AMS top mounted and I am not sure it would be a good idea with these feet.

My AMS is on the side, and it actually wobbles less as the table can't transmit the printer's vibrations.

Obviously, you need 4 squash balls.

Each foot is different because of minor tweaks for fitting, they are embossed to avoid any mistake.

I used double sided tape on the horizontal contact area to stick the feet to the printer.

Please rate, it's beneficial to everyone.

Happy printing😋