Can I output the audio from the RaspberryJAMMA DAC to headphones or a 2.1 set without cab mod?

Questions about the RaspberryJAMMA adapter.

Moderator: dee2eR

Post Reply
lobdale
Community Member
Community Member
Posts: 17
Joined: Tue Sep 22, 2020 4:17 pm

Can I output the audio from the RaspberryJAMMA DAC to headphones or a 2.1 set without cab mod?

Post by lobdale » Fri Dec 11, 2020 2:58 pm

Me again...

I have read about how to mod for stereo/add a receiver to the Astro City cabinet mainly because I have an interest in using headphones on the cab when it's late in the house or my kid is asleep, and have not been looking forward to all the hacking up that seems to be required to do that.

But then it occurred to me, I'll be mainly using the RaspberryJAMMA, and it has a stereo output jack both on the Pi and on the onboard DAC...

So, would there be any issues leaving the DAC output to the JAMMA board connected as normal when I want sound to go through the cabinet, and then just removing the cable that goes from the DAC to the JAMMA board and plugging a pair of headphones into the DAC when I want to use headphones? It won't draw more power off the cabinet's power supply or bork it in some other way I'm not considering, will it? Alternatively, would this also be a way to output the audio to a 2.1/externally powered system to use a subwoofer in the case that I wanted beefier audio than the cabinet speakers provide?

Many thanks for your continued support.

dee2eR
Inventor
Inventor
Posts: 1854
Joined: Tue Aug 22, 2017 2:07 pm

Re: Can I output the audio from the RaspberryJAMMA DAC to headphones or a 2.1 set without cab mod?

Post by dee2eR » Fri Dec 11, 2020 11:28 pm

The DAC audio output is indeed in stereo and can be useful source for external 2.1 systems. However it is line level (not amplified) and will probably not suit headphones very well (will vary greatly from set to set depending on the headphone specs). It shouldn't hurt to try the headphones with the DAC output if you want to try it, just don't expect amazing results.

One other thing to consider is bypassing the onboard mono JAMMA audio amp also bypasses the volume knob, which won't be an issue with a 2.1 system (as they usually have their own volume control) but may be a deal breaker for directly connecting headphones.

Probably the easiest way to do both would be to use an amplified stereo (or 2.1) system that has it's own headphones output as well.

The audio is in stereo at the DAC (and mixed to mono on the RaspberryJAMMA before amplification) so just using the line out of the DAC is all the config you need - no need to adjust settings in software or anything like that.

To use the RPi analog audio output would require software changes and would most likely not sound as good as the DACs output.

lobdale
Community Member
Community Member
Posts: 17
Joined: Tue Sep 22, 2020 4:17 pm

Re: Can I output the audio from the RaspberryJAMMA DAC to headphones or a 2.1 set without cab mod?

Post by lobdale » Sat Dec 12, 2020 2:05 pm

That is awesome news! I'll have to get an inline volume dial for the phones or decide on a 2.1 system.

I'm gonna start off by just using a really cheap portable headphone amp (1/8" input and two 1/8" amplified outputs with volume control) and see how it goes for when I want to use the phones.

Post Reply