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QuickVoice voice memo recorder is a third party app that does not store the sound files in the same location the iOS built-in voice memo recorder does.
First go to DiskAid Preferences and under Storage check the 2 top boxes enabling to show all apps and to show the root folder for these apps.
Then in DiskAid click on Apps and look up for QuickVoice.
The recordings are stored within this third party app's (QuickVoice) documents folder. The good news is that DiskAid file transfer feature will copy them to your computer just as well as the original voice memos.
The capture below displays the QuickVoice app voice memo files' location in DiskAid.
Notice that in the storage sub menu I have selected the QuickVoice App to begin with.
Whether using a Mac or a PC I showed the Mac interface but once you get to the Apps it's the same with the Windows' version.
The file format QuickVoice is CAF that can be opened and read by QuickTime.
One more thing, both on the Mac and the PC version you can drag this "Documents" folder to the navigation bar to create a shortcut, so you won't have to remember where these voice memos are in the future: