Does your DAC have a toslink optical input?
It seems like all you need is an Apple AirPort Express (APE). The APE has an optical digital output, which means that you'll need a "mini toslink" cable. Since you use an iMac, iTunes and AirPort Extreme, it should be a simple setup. By adding the APE you will be able to stream iTunes and other AirPlay applications.
There are 3 cable manufactures that make high quality "mini optical" cables:
1. Lifatec Silflex
2. WireWorld SuperNova 6
3. VanDenHul Opticoupler
Let me know if you have any questions or need help.
It seems like all you need is an Apple AirPort Express (APE). The APE has an optical digital output, which means that you'll need a "mini toslink" cable. Since you use an iMac, iTunes and AirPort Extreme, it should be a simple setup. By adding the APE you will be able to stream iTunes and other AirPlay applications.
There are 3 cable manufactures that make high quality "mini optical" cables:
1. Lifatec Silflex
2. WireWorld SuperNova 6
3. VanDenHul Opticoupler
Let me know if you have any questions or need help.