I think people need to consider that the design was clearly just a proof of concept, junk-box amplifier and likely never intended to take on this highly profitable life it has subsequently been saddled with. Kitset vendors have climbed aboard the DIY gravy-train, exploiting the ignorant 'maker-movement', peddling the parts in an over-priced Italian case and now it costs an almighty US$329, which is a sad joke and does nothing to further perceived value in build-it-yourself projects.
The original BOM is here (for NP's 2012 PDF)
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(per channel)
Basically, the entire concept of building a little junk-box amplifier as an afternoon project for fun, has been bastardized by profiteering hangers-on and that's hardly NP's fault. His gifts to the DIY community are numerous, respected and sometimes polarizing, but universally appreciated.
In terms of performance, it's a joke THD wise- we all know that, but if it cost just $30 for the parts you didn't have in stock, and the rest you pulled out of your junk bin or scavenged, it was no doubt a pile of fun.
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