Match impedance from 600 ohm/2kW tube amp to 8 ohm/25W speakers
Whatever made you think this can drive speakers , was incorrect. This tiny tube circuit can only buffer 47k Ohm phonograph signals to a pre-amp and add some hum. 


get google to translate this over-enthusiastic review. https://www.google.ca/amp/s/geardiary.com/2017/12/01/audiophile-budget-fx-audio-tube-01-best-tube-buffer-money/amp/


This IS NOT A POWER AMPLIFIER or PREAMP.