Portable DAC recommendations

There was a post on Headfi from an Oppo design engineer who said he could not hear a difference between the two units except hiss from some iems was cured.

 

This is all you need to attach a 30 pin connector to an HA-2 or HA-2SE. I can confirm that an iPod Classic works just fine with an HA-2(SE) using a cable like this.

 

No wonder the headphone output on the LG G5 is lacking. Saw this chart and it has almost half the output of my old phone and nearly 3 quarters less than the new LG V20. WOW.

Audio output

Headphones output power (Volts)
HIGHER IS BETTER
LG V20 - 0.99

LG G3 - 0.57

LG G5 - 0.29

Loudspeaker loudness(dB)
HIGHER IS BETTER
LG V20 - 72

LG G3 - 81

LG G5 - 73

 

Wow! is right. That certainly explains why you're not getting enough volume when plugging the headphone jack into your car's AUX input. An external portable headphone amp would be almost mandatory to get any sort of useful output when the headphone jack is that wimpy.

Another possible solution could be a Bluetooth adapter for use in the car.
Something like this: https://www.amazon.com/Belkin-Hands-Free-Bluetooth-Versions-Smartphones/dp/B004CLYJ2I

Bluetooth is lossy. So you're going to lose some audio quality. I've never used any of those sorts of Bluetooth adapters in a car. I don't know how well they would do for audio quality and how good (strong) the analog AUX output signal would be.

 

I actually have one of those and the volume is a little better although still not great, but the soundstage is very narrow and not as clear. I do use this when listening to talk radio or podcasts. But it is hard to listen to my FLAC HD files through it when i know how it is supposed to sound and it just doesn't.