The Geffen Dolby decoder will work without changing the default setting of the TV's digital audio output, however when the TV's digital audio output is set to "PCM" any 2 channel DAC with optical input will work.
Showing 2 responses by tls49
You need a basic 2 channel DAC with optical input and an optical cable.
Here’s a decent budget DAC for $23 with a cable or $18 without a cable. I have one of these and it did come with a power supply but there seems to be some conflicting information on the Amazon page. And yes, you can go for a more expensive DAC, but this one will solve the problem.
The L&R output of the DAC connects to your preamp with a standard RCA audio cable.
Also, and very important - You will need to go into the settings of the TV and set the digital audio output to PCM. This is not the default setting.