Sansui QRX Semi “Holy Grail” Modification


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New member
May 26, 2024
Washington, DC
I have a QRX-9001 fully restored in 2012 by Jim at QRXRestore, including the Holy Grail modification. With the vast majority of source material, the modified variomatrix circuitry produces no noticeable artifacts. But with certain source material, like massed vocals or synths, the separation gets a bit grainy, like with the Tate 101A or Audionics Space & Image Controller. I’ve recently acquired a QRX-7001. I’d like to do a semi Holy Grail mod on this unit, meaning instead of fully maximizing separation as with the Holy Grail modification, perhaps splitting the difference between the factory default and Holy Grail, to achieve better than default separation but with smoother operation than the Holy Grail. Would this be as simple as replacing the 3 Holy Grail capacitors with capacitors rated at 1/2 their original resistance, instead of replacing them entirely? Would I then still need to perform additional voltage adjustments?