Which tubes are particularly suitable for Luxman tube devices if the original configuration is to be replaced?

With Luxman, the tube choice should always closely follow the respective model. A good example is the MQ-88uC with KT88, the compact SQ-N150 with ECC83 and EL84, as well as the MQ-300 with 300B and 6SN7GTB. Especially with Luxman, it is usually less about experimenting and more about a coherent, high-quality tube configuration that preserves the character of the device. Many suitable types are available from BTB in selected quality, with power tubes also available on request as matched pairs or quartets, as well as rare types such as 6240G or 6336.