Help with connecting to an A/V receiver/5.1 system

[Kansas_Vol]

Hi,

Hoping for instruction/advice: I’m trying to connect a MacBook Pro to a 5.1 surround system. Components are a 2023 MacBook Pro 13” M2, Denon AVVX1400-H receiver that I bought in 2017 and a CalDigit Thunderbolt 4 Pro dock that I bought from Apple yesterday. I tried connecting from the rear headphone jack on the dock to the optical input on the receiver using a Toslink to Mini Toslink digital optical S/PDIf audio cable. System settings seem correct in that it showed TS4 as the speaker output. However, no sound. So, a couple of questions:

1. Are there any system settings that I'm missing?
2. Do I need an external DAC?
3. Will a USB-C to HDMI cable work instead of the Toslink cable?

Thanks in advance for any input!

 

[PaulD-UK]

Are you sure the dock has digital audio out?
It only seems to mention 3.5mm headphone audio out in the specs.

 

[Kansas_Vol]

Yes. It has audio-out jacks on the front and back for headphones and one audio-in on the back as well.

 

[PaulD-UK]

But those are analogue only? Not miniTosLink digital?
So yes, you need to connect the Mac to an external digital output device

 

[Kansas_Vol]

Thanks PaulD. I thought the newer macs had a built in DAC? Is this not the case?

 

[arw]

Thanks PaulD. I thought the newer macs had a built in DAC? Is this not the case?

Yes, Macs do have built-in DACs. DAC means Digital-to-Analog Converter. Analog is something like a pair of headphones connected to the headphone jack. Which of course works.
But you do not want an Analog signal out but a Digital one. Like Toslink / SPDIF. Which MacBooks released after 2010 unfortunately lack.
You are also out of luck with your CalDigit Thunderbolt Station 4:

CalDigit eliminated the Optical Audio connection found on the TS3 Plus and replaced it with the 3.5mm rear audio jack out.

https://9to5mac.com/2022/03/05/caldigit-ts4-review/
What you can do is connect the TS4 dock to your AV Receiver via one of the following two options (which also transmits a video signal):

• DisplayPort → Active DisplayPort to HDMI adapter → HDMI cable
• USB-C → HDMI adapter /cable

I suspect the latter would be the most feasible (USB-C → HDMI cable).
Which is also the answer to your question:

3. Will a USB-C to HDMI cable work instead of the Toslink cable?

I use this one with my Mac which supports up to 4K @60 Hz.

https://www.amazon.com/dp/B075V5JK36

If your receiver/display had Thunderbolt/DisplayPort inputs, additionally the two following options were possible with the TS4 dock:

• One of the two available Thunderbolt ports
• DisplayPort 1.4 port

BTW, all of these options are definitely the better solution compared to optical as the latter does not support:
7.1 sound, multichannel LPCM, Dolby Digital Plus, Dolby Atmos, DTS:X or high-definition audio such as Dolby TrueHD and DTS-HD Master Audio.
https://www.the-home-cinema-guide.com/optical-digital-audio.html