Yes and no. Sonically, Bakoon and Questyle make up a particular sonic flavor. Technically, they are based on the same principle, but differ in final execution. [Spoiler alert: I'll very probably tell crap. I just repeat what I picked up here and there]. I think it was called transimpedance or transconductance (or concordance, I don't remember). Such amps basically don't amplify the signal like conventional amps, that is, they don't copy and boost the input signal's voltage/current. They rather unblock the output current that wants out the whole time but is blocked by the input signal. No input signal, no way out. The stronger the input signal, the lower the resistance that impedes the output, and the more current can flow to the headphone. There is no upscaling of the input needed as the voltage is preset by the potentiometer, but the current is limited by the input. It reminded me very much of signal transmission in the eyes. Actually, the signal towards the brain is constantly turned on but the way is blocked until there is some light that triggers those blockades to free the way.
The stupid thing is that Questyle copies the transimpedance signal and uses a conventional signal (whatever that means). But sonically, it results in a similar sound to Bakoon amps. BTW, Grace and BMC use the same principle in their DACs. It's not that special either.