Pros: Portable, compact, light, sturdy
Cons: Incompatible with USB 3.0, slightly narrow soundstage, sounds muddy with higher-end headphones
SMSL Fort USB DAC is a quite affordable, very portable USB DAC with volume control pot on the top. The DAC is housed in a CNC machined black aluminium cylindrical casing with dimensions of 50 mm in diameter, 38 mm in height and 72 grams in weight. It is capable of outputting 130 mW of power with 32 ohm load and its Burr-Brown PCM2704 chip supports the following sampling rates: 32/44.1/48 kHz@16 bits. The headphone jack is 3.5mm in size. The DAC comes in a plain cardboard box with a white USB-Mini USB cable.
OS: 64-bit Windows 8
Player: Foobar2000 (Kernel streaming)
Source material: FLACs ripped from CDs
Headphones/in-ears used: Thinksound TS02, Superlux HD 622F, Hifiman HE-500
I compared the SMSL Fort against my main setup which is Audio-GD NFB 3.1 and Meier Audio Corda Classic. Powerwise the Fort handled all of the headphones very well, it had plenty of power to spare. Even with HE-500 I didn't have to crank the dial past nine o'clock (the dial goes from 6 to 4 o'clock). I mostly used my Hifiman HE-500s for the sound quality tests. The sound seemed quite neutral but a bit thin. The bass lacked a bit of that familiar punch and highs were not as high as I was accustomed to. All in all the sound was nicely balanced but the lack of power was clearly showing with the HE-500s. The Superlux HD662F was a much better companion to the Fort as the shortcomings of the DAC/AMP were not as apparent due to the lower quality of the headphones.
The DAC does not function with USB 3.0 ports. On the brighter side, on USB 1.1 and 2.0 ports no separate driver is needed because Windows recognizes the DAC automatically.
If you have a crap sound chip in your computer and you don't want to break the bank, invest in the SMSL Fort. It is a good upgrade to an integrated chip especially if you can get it cheap.