Hey Albert - I'm marking the day on the calendar that you've adopted PC audio as an option! What's the rest of your digital delivery system chain?
For those who want to use iTunes with a variety of file types, including FLAC, there is one other possible solution, besides the aftermarket piggyback software that Albert suggests, that I use. Squeezeserver, which controls Squeezebox devices like the Touch, can catelogue/control both your iTunes library and a separate music folder, simultaneously, that includes most file types including FLAC. The only downsides is that, A) you are limited to using Squeezebox devices to deliver the goods to your DAC which is not necessarily a bad thing if you use Ethernet cable to network to them (even wireless is pretty damn good), and B) and this may be a deal breaker to some - I'm pretty sure even the best of those devices, the Touch and Transporter, are limited to 96/24 so if you have higher rez you'll have to find a different solution or settle for a downsampled version (buzzkill). Someone correct me if I'm wrong there. There are various controllers that work with SB devices via an iPhone or an iTouch, including iPeng and now Squeezebox makes their own free controller which is actually quite good. The later is free, while iPeng costs a small fee. I control three SB devices from my phone with those apps with the option of synchronizing any two or all three or none at all. The SB Touch has excellent jitter specs on the SPDIF output, and the AKM DAC in the Transporter is quite good and made even better by a Modwright tube output section. The DAC in the Touch is passable but not nearly as good as the one in the Transporter.
Good suggestions from Albert on MacMini configuration.
On duplicate files - check your library and see if there are actually several copies of those files, or whether iTunes is just cataloging a single copy as several copies. If the latter I believe you can rebuild your library by scrapping your existing iTunes folder (save a backup), then pointing iTunes towards your storage drive(s) to build a new library. If you start up iTunes with the "option" key (Mac) held down (not sure what PC uses), iTunes will give you the option of starting up from the music folder of your choice (this is also handy if you want to investigate another library or switch libraries). Perhaps the simplest way to do a check for actual duplicate files on your drive(s) is to choose any song or album that registers more than one copy and do a simple search on that title on the drive(s) that store your music. If it comes up only once in that search then it is an iTunes cataloging issue, and should be solved by rebuilding your library. If you do that you might want to keep a copy of your current iTunes folder as a backup just in case.
Good luck!
For those who want to use iTunes with a variety of file types, including FLAC, there is one other possible solution, besides the aftermarket piggyback software that Albert suggests, that I use. Squeezeserver, which controls Squeezebox devices like the Touch, can catelogue/control both your iTunes library and a separate music folder, simultaneously, that includes most file types including FLAC. The only downsides is that, A) you are limited to using Squeezebox devices to deliver the goods to your DAC which is not necessarily a bad thing if you use Ethernet cable to network to them (even wireless is pretty damn good), and B) and this may be a deal breaker to some - I'm pretty sure even the best of those devices, the Touch and Transporter, are limited to 96/24 so if you have higher rez you'll have to find a different solution or settle for a downsampled version (buzzkill). Someone correct me if I'm wrong there. There are various controllers that work with SB devices via an iPhone or an iTouch, including iPeng and now Squeezebox makes their own free controller which is actually quite good. The later is free, while iPeng costs a small fee. I control three SB devices from my phone with those apps with the option of synchronizing any two or all three or none at all. The SB Touch has excellent jitter specs on the SPDIF output, and the AKM DAC in the Transporter is quite good and made even better by a Modwright tube output section. The DAC in the Touch is passable but not nearly as good as the one in the Transporter.
Good suggestions from Albert on MacMini configuration.
On duplicate files - check your library and see if there are actually several copies of those files, or whether iTunes is just cataloging a single copy as several copies. If the latter I believe you can rebuild your library by scrapping your existing iTunes folder (save a backup), then pointing iTunes towards your storage drive(s) to build a new library. If you start up iTunes with the "option" key (Mac) held down (not sure what PC uses), iTunes will give you the option of starting up from the music folder of your choice (this is also handy if you want to investigate another library or switch libraries). Perhaps the simplest way to do a check for actual duplicate files on your drive(s) is to choose any song or album that registers more than one copy and do a simple search on that title on the drive(s) that store your music. If it comes up only once in that search then it is an iTunes cataloging issue, and should be solved by rebuilding your library. If you do that you might want to keep a copy of your current iTunes folder as a backup just in case.
Good luck!