Our inspirations and supply come from the following sources:
References
https://www.naimaudio.com/sites/default/files/products/downloads/files/ndx-white-paper-oct-2010.pdf
http://www.crazy-audio.com/tag/dac/page/3/
http://www.tnt-audio.com/clinica/diginterf1_e.html
http://audioberry.com/hardware/beginners-guide-raspberry-pi-i2s-audio/
Regulators & PSUs
http://www.neilmcbride.co.uk/preamp.html
http://www.teddypardo.com/diy/buy/superteddyreg.html
DACs
https://volumio.org/forum/list-i2s-dacs-for-raspberry-t1103.html
OS
https://sites.google.com/site/picoreplayer/home
https://en.wikipedia.org/wiki/Naim_Audio_amplification
http://www.tnt-audio.com/edcorner/prat_e.html
future TDA1541A project
http://www.lampizator.eu/lampizator/TDA1541%20corner/TDA1541.html
http://lampizator.eu/LAMPIZATOR/Lampizator.html
http://lampizator.eu/LAMPIZATOR/photogallery/STEPS/Lampizator.doc
http://lampizator.eu/UPGRADE/upgrade%20noval%20tubes%20to%206H6P.html
https://github.com/iancanada/DocumentDownload/blob/master/README.md
https://github.com/iancanada/DocumentDownload/tree/master/PCMboard
http://www.abbasaudio.com/index.php/cat/c34_1-Produkciya-Abbas-Audio.html