Good headphones provide excellent listening quality when paired with a good headphone amplifier such as this Spartan 30, for example.
In fact, the new Michael Fidler Spartan 30 is not only a headphone amplifier, but also a pre-amplifier. This extra makes the device just a little more versatile. Central pivot of a headphone amplifier (and also preamplifier) is a good volume control. This is what the manufacturer claims to have paid extra attention to, eventually opting for an industrial potentiometer after much comparative research. The chosen component stood out above the other candidates in terms of equalization and durability.
NJM5532
You have three high-impedance RCA inputs at your disposal with the Spartan 30. Internally, the selection of a chosen input takes place via Panasonic relays. Type NJM5532 opamps are used in the circuit, which are also neatly placed in sockets. In any case, we are talking about an extremely service-friendly device here, because there are only regular parts on the PCB. SMDs you will look for in vain. The headphone output delivers up to 700 mW into 150 Ohms. A nice upgrade for anyone who wants to take headphone hi-fi to the next level.
The Spartan by Michael Fidler 30 will cost you €550.