I have two moded sacd machines. Neither is just a parts upgrading. One the Allen Wright Sony 9000 has a new board in it, and the other an Exemplar (Tucker) Denon 2900 has a tube analog stage in it. Both are greatly superior to stock units both for sacd and cd. The Wright unit costs $1000 plus a Sony 9000 for a total of about $1600. The Exemplar/Denon cost $3000 including a new Denon. For these prices they rival or exceed units costing $10,000-$20,000.
On both good sacd is clearly superior to good cd, but good cd is superior to poor sacd. On the Denon good sacd is superior to good dvda.
On both good sacd is clearly superior to good cd, but good cd is superior to poor sacd. On the Denon good sacd is superior to good dvda.