Many amp builders rely on Monolith Magnetics for custom designed components. Small series or one-off items. In the pictures are 4 big 2.4kg each layer wound dual C-core chokes for a customer in Norway. These are tailor made 30H 0.1A chokes for choke input filtering withstanding 1100V AC/100Hz without saturating. They’ll find their spot in the power supplies of GM-70 monoblocks. 

These chokes are made to the exact customer specs including the required DC resistance of 105 Ohms +-5%.