[abellmc019]

Which is worth getting?

 

[cel4145]

I think the D1 would work better as a door stop given it's larger size

It is April Fools, and you did forget to talk about what you wanted it for, what equipment you have, how you intend to use it, etc.

 

[abellmc019]

Intend to use it to improve the sound quality of music coming through laptop, then through speakers. The D1 is more inexpensive, are there any acoustic advantages to the D3? The D3 is obviously an easier set up and more convenient with a slimmer form factor. This decision is the difference between spending $120 and $190. Did hear from W hatHifi that the second incarnation of the Dragonfly USB DAC was a big acoustic improvement over the first version for less money.

 

[cel4145]

Even the first Dragonfly is supposed to be very good, and the Dragonfly has been extremely popular on Head-Fi, more than the Audioengine D3: http://www.head-fi.org/t/617241/audioquest-dragonfly-review-affordable-outstanding-tiny-dac-amp

Given the popularity of the Dragonfly, someone in that thread might know how it compares to the D1.

Meanwhile, I would think the D1 design might be more convenient if you plan on using headphones since it has both a headphone jack and RCA outputs for speakers.

 

[ChinBo37]

I have the D1. To me it sounds amazing but then again its my first DAC so I dont have a lot to compare it to. I dont think you would be disappointed though. 
 
Just remember it can only handle 24bit/192khz through optical input so remember that. USB input handles up to 24bit/96khz. Also remember if you run optical input you still need to run USB power, so I picked up a usb wall wart connection.
 
 
IMO this is a great DAC, I havent heard the D3 but if you want a more portable solution that may be a better bet.

 

[abellmc019]

Likely wouldn't use an optical output. Which USB DAC supports 24/192?