Headphone Tube Amps - Follow-up & Tear-down

Due to 'popular' demand - in this video I revisit the Budget Headphone Tube Amplifiers from an earlier video - run some tests and tear them down in an attempt to discover whether the tubes are functional or just decoration. CLICK 'SHOW MORE' TO EXPAND
The NTNON Hi-Fi shop sketch:
My original Headphone Tube Amp Video:
PLEASE DO NOT SEND ME ANY MORE LINKS TO THE TEAR-DOWN VIDEO BY EEVBLOG
Important note. I am fully aware of the tear down video by Dave at EEVBlog of one of these headphone amps, which he kindly performed to lay this matter to rest.
My first video about these headphone amps was uploaded in September 2015, a kind viewer went on to send Dave one of the amps so he could perform a professional tear-down, which he subsequently did in January 2016.
If you haven't seen Dave's video...here's a link.
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