My amplifier came in today, and I have been listening to it (straight) for about 8 1/2 hours. First, I don't believe I am coaxing the best out of this little gem because I am stuck using an unbalanced connection between my DAC and the amp (I am still awaiting the cable to run it via balanced), and the DAC I am using (DX300) with the stock amplifier card does not have a true LO (it is called LO mode but it is not bypassing the amplifier circuit). Once I get the dual XLR connector to 4.4mm I can run it from my other amplifier card that has a true LO jack available to use, and I am sure things will sound immensely better.
Having said that, it still sounds brilliant with most of my head gear (so far). I haven't taken too much time to test out the tube and tube+ mods, but SS mode is sounding really good with the majority of my collection. I find the X-bass to be subtle in most cases all the way up to 40Hz, where it becomes a big boost (nothing subtle there). There are a couple of sets that I have that will make known the different settings though. I find the quantity very pleasing depending on my mood (though I am no bass head for the most part). The only negative I might "nitpick" is the quality and overall punch (or lack thereof) of the amplifier altogether. But, this could just be that my DX300 that I am used to has more punch and is more visceral (even with sets that lack quantity) than the iCan Sig, or that I am basically "double amping" the signal ATM. I don't find it detracts too much from the enjoyment of the amp though.
Another beautiful feature for me is the 3D Holographic feature, but not for the reasons that is explained that this feature is supposed to do. I don't find that it widens the staging at all with any of my headphones, IEMs, flathead earbuds. BUT.... where I love it is that (to my ears) it either lowers the mids a bit to sound more recessed a bit, or boosts the treble to give more perceived clarity in the overall tone of the notes, or both at the same time because it makes most of my gear (seemingly) have a bit of a V signature to them. So, for me this is more like X-Treble than 3D Holography....
Great implementation anyhow because this isn't a subtle effect either.
Man! This thing has some power to it. I have a set of flathead earbuds (Yinman 2.0 600) that are both super high impedance, and also super low sensitivity making them one of the hardest pieces of head gear that I have (600ohms @87dB/mW). I am not able to get much volume out of the 4.4mm balanced connection (as expected after reading about the output power from that jack) but coming out of the balanced XLR connection, I can get deafening volume levels in low gain. I DO think that 9dB or 18dB make them sound more dynamic though.
Also, probably a bit dim on my part, but there are no instructions or diagrams showing the proper way to install a battery in the remote. I found the cap at the bottom of the remote that has to be removed, but I see no markings or an obvious installation method or markings for the battery. Am I just supposed to "shove" it in until it bottoms out, and which is plus and which is minus??? LOL
Edit: OH! Also, I am positively sure that my impressions can/will change over time as the caps are conditioned, and settle.