Replace HDD in Sony HAP Z1ES with an SSD

One note, the HAPZ1 will only recognize an internal drive up to 2TB.  My understanding is a USB drive can be larger, but I haven't tried that.

Thanks for your help. As it turned out, I had the work done by Modwright with their upgrades. I can barely bring myself to turn it off! 

Very easy to do with the instruction on the web sfseay mentioned . Takes about 15 minutes . I did it as well .

I had to speak to a colleague who's an engineer (I teach Liberal Arts, meaning I'm clueless). He said firmware likely limits the amount of real estate the HAP Z1ES will recognize - though that is a generality, not specific to any particular app. He also mentioned that a NAS (RAID 6/4 disks) can be connected via USB. I have done this, and I can hear no degradation of performance through Audible Illusions m3a Pre/MC 275 VI monoblock/Harbeth 40.1/REL Britannia.
That makes capacity a non-issue - 4 3tb disks in RAID 6 yields 9+ TBs, or about 10,000 cds. If you have more than that, please invite. I'll bring Macallan 18!