Last month I showed the first headphone amp I ever built. That one was meant to be used with a preamplifier, hence it did not have input selector or volume control. This month I finished another version of that, this time with input selector switch and a volume attenuator at the input so sources can be connected directly to it.
It is based on the same circuit and component selection as the previous one, just with the selector added and a resistive ladder type volume control.
While the previous one had all the taps of the output transformers brought out to individual jacks, this only uses one of them to make room for the control switches.