Counting – In German, zählen means to count. And Zähl Elektronik's HM1 headphone amplifier [€8'000] would seem to count; big. With 40 watts of class A draw at idle, the circuit adds a servo to correct source/load errors by adapting the output impedance to less than the sum of headphone cable and input impedance. To enable easy A/B comparisons, two inputs feature independent attenuators and on/off switches which a wired remote can trigger. A mixing function allows gradual fade in/out or two-source mixes which can be routed to the RCA/XLR line outs. Treble/bass controls offer three fine steps each and there's a control for soundstage width not based on crossfeed which the 'direct' switch will bypass. The HM1 is built at just 50 pieces a year and sold exclusively through AudioNext in the German-speaking markets.
