The S.M.S.L. AO200 is a small/desktop integrated amplifier with Bluetooth, USB, unbalanced and balanced inputs. There is one set of speaker outputs and subwoofer outputs.
There is an excellent little display on the front of the unit for status, etc. The volume control is smooth, and it also acts as an input device with a press to select operate the menu. The unit also comes with remote control.
The USB A input can accept a USB stick with digital files; there is no playback control; it just plays them in order. S.M.S.L. provided a unique USB A to A cable that connects to your computer for playback as a USB DAC.
The D.A.C. in the AO200 is a fixed rate unit 24/48, which is similar to the D.A.C. in my Audioengine A2+ speakers. These seem unusual to my audiophile brain.
The compact size of the unit presents some issues. First, the speaker terminals are tiny, and because they are so close together, they are tough to connect wires. The R.C.A. connections are also too close to each other for comfortable use.
My initial use case was to improve my desktop sound system. The folks at High Fidelity Services, Neat Acoustics' USA Distributor, sent over a pair of the Neat IOTA speakers in their blue color. Thanks Paul! I set them up on Isoacoustics stands to isolate them from the desk. The IOTA speakers are horizontally oriented. You can swap the left and right to put the tweeter on the inside or the outside.
My desk is in the corner of my office. The "magic" equilateral triangle is impossible with two 27 in. monitors in-between the speakers. I was able to get a pretty good sound stage presentation in the corner. But, I found that it was better when I went to my other desk with a flat wall behind it and only one display. In that location, the staging was much simpler to get "right." Close near-field setups are tricky to get right. My case is worse than many.
Most small desktop speakers can use some help on the bottom end of the spectrum.
One of the features of the AO200 is a subwoofer out. I tested this with a R.E.L. T0 Subwoofer. Setting this up over a short term was not as simple as I had hoped. It took me several days of listening and adjusting until I found the sweet spot. The subwoofer balanced the system out rather nicely. For this class of design, it might be too much cost.
While I had the setup in my office, I tested both the balanced and unbalanced inputs from my Soekris DAC2541. The sound quality over those inputs is a natural step up from the internal D.A.C. or Bluetooth. Of course, I added a $1400 DAC in front of the $279 integrated amp!
I did a few days of listening using my Volumio Primo via their analog out into the speakers. While this sounds pretty good, you start pushing the price up into other hardware that might be a better fit, such as a BlueSound Power Node. In addition, I use Roon as my primary streaming system, so adding Volumio is a bit of extra work I do not want to do.
During this testing, I had no way to compare other amplifiers in a meaningful way. I did some casual testing with an older Rotel class A/B system, and there was no significant difference for the applications.
The system ended up in my workshop, where I am moving around more and is a bit more casual listening. I use Bluetooth from my iPhone in the shop, and I am using a Raspberry Pi running Vitos hooked Via USB to the AO200 as a Roon Endpoint. I am using the NEAT IOTA speakers for now. They will be leaving soon, so I will hunt for small speakers for that room.
Thinking about use cases such as a garage system or my shop, where you want music, podcasts, radio, etc. In those cases, the compression on the Bluetooth link or the lower performance of the USB input is not a limitation. The AO200 might work well in a dorm room or bedroom system.
The AO200 is a building block for the playtime audiophile. It is priced well for the features; it looks good and takes up very little space. The manual is overly brief and needs expansion. The size of the case is a blessing and a curse for connecting all the wiring up.
I am not sure what speakers I would pair with the amp. Time and budget do not allow for any research in this area. I leave that up to you, dear reader.
While the AO200 did not end up at my desk it is now the “basement/workshop” system for general use. With Bluetooth and Roon using a Raspberry Pi, it is NICE!.
I continue to use my Audioengine A2+ speakers in my office because they image almost perfectly due to the front ports.
I have returned the subwoofer. It was Wonderful, but not really in the budget.