IMAC i7 to 5.1 surround (Audio Midi Setup)


macrumors newbie
Original poster
Dec 15, 2011
Here's the scenario:

I have an Imac i7
Denon AVR 1712
Toslink cable.
5.1 speakers

I have the Imac running optical out to the optical in on the receiver. I am trying to configure the sound from the audio MIDI setup on the iMAC. When choosing the output it only allows for Stereo (the other options are greyed out and non clickable). Is it up to the receive to decode the surround information or do I need to do it from the Audio MIDI setup and choose the 5.1 setup.

Also, is there any way to choose the onscreen setup options for my AVR to show on the Imac screen?

Finally, are there any other programs I need, to view and hear 5.1, or can I do it from the installed DVD player on the imac.



macrumors G5
Jul 29, 2011
Somewhere Back In The Long Ago
My 27" iMac is connected to my 7.1 DTS system but not from the mac itself.

Bear with me because I have a new TC and have changed things a little:

My iMac is connected to the internet via a gigabit router

My DTS system is connected OPTICALLY to the optical port of my ATV unit.

SInce all devices are on the network, this streams audio without being connected to the mac.

If you don't have an ATV, and I'm guessing not, you could buy an Airport Extreme and use that to connect your audio system.

I think the small AE units are around £79.00, the ATV2 is not far off the same price.

My DTS does not show up on the iMac, I just use the small icon in iTunes to play to the ATV.....Effectively playing to the network.


Also should have said.HDMI on the ATV is connected to a 42" smart TV.


macrumors 6502a
May 8, 2011
Endwell, NY
I don't believe you need to do anything in the Audio MIDI setup. Have you tried playing a DVD to see if it outputs the correct 5.1 discrete surround yet?

I could be wrong... never played a DVD from my optical-out Macs, but I never needed to set anything up for my sound output when using TOSLINK.


macrumors member
Jul 18, 2011
Start up the DVD player without inserting a DVD;
Preferences>Disk set up>Sound>Sound out set to digital out

This should do the trick....


macrumors newbie
Original poster
Dec 15, 2011

OK, it looks like I have 5.1 through AlexBerkman's suggestion.
So, if others are trying to do this without Airport express or ATV; A toslink cable from the headphone jack of the imac to the optical in of the AVS receiver will process the sound.

Unfortunately, I have an on screen set up process for the the Denon 1712 AVS receiver, and it doesn't communicate with the iMAC. And the denon has a 130 page manual. I still have my work cut out for me. Has anyone else taken on this project?