Marantz HDAM

[toufu]

Hi, is anyone familiar with the Marantz HDAM or HDAM SA circuits? Do the transistors need to be matched? And are the covers really necessary?

Thanks.

 

[Jebem]

You may find some useful information on this site. Just search for HDAM. For example, see if the following posts help You:
http://www.diyaudio.com/forums/digital-source/162029-marantz-hdam-tweak.html
http://www.diyaudio.com/forums/analog-line-level/150349-marantz-hdam-preamp-diy-kit-ebay.html
http://www.diyaudio.com/forums/pass-labs/40201-x-hdam-opamp-newbee.html