I submitted an unflattering review of this amp a few months ago that was not published. I feel moved to try to share my experience again.
First of all, other than that review not getting published, I have been very happy with B\oom Audio's customer service and their willingness to work with me on a number of purchases that have now totaled over $9000 in just the past 13 months. All of the equipment I have bought from B\oom has worked out very well. Until this iFi Pro iCAN Signature. It took me about a month to begin really listening to this amp and, when I did, I heard what sounded like noisy tubes in both tube stages, and when switching between solid state, tube and tube+ stages there were loud - I mean reflexively rip the headphones off your head loud - popping noises. I had the amp for 33 days at that point and B\oom suggested I send it to iFi for service rather than them replacing it for me. Ok. Its been over 30 days....
Really poor communication aside, iFi finally let me know the main board on this amp was defective. They replaced it and shipped it back. I received the repaired amp and this time the amp went into overload mode (the lamp on the top left of the front faceplate blinked red) and the amp shut down every time I engaged either of the tube stages. At this point I demanded iFi replace this lemon with a different unit which, to their credit, they did. This new unit ALSO (sometimes) goes into overload mode when switching from solid state to tube mode but, when it does, it has always returned to an operable condition within a few seconds. So far.
Other than these minor annoyances (sarcasm), this is the most versatile and one of the best sounding amps I own. I purchased (quite excellent) headphone cables from Forza Audio Works to access the pair of three-pin balanced XLR outputs for some of my headphones. I prefer using the amp's soundstage adjustment to get a more natural speakers-in-the-room separation and I appreciate the options of using different output stages, output jacks, and having an adjustable bass shelf. It's a great little amp with a very pleasing sound. If only the factory's quality control process was up to the task, this would be a fantastic amp that would receive a five-star review from me. I primarily listen to this amp direct from my Denon DCD A110 Anniversary Edition SACD player as well as streaming audio through my Gustard X26 Pro DAC.
Other amps I have that I've compared this to, and still found the iCAN Signature at or near the top in terms of sound quality and enjoyment:
Feliks Audio Espressivo Mk II, Burson C3R with Burson Super Charger PSU, HIFIMAN EF400, RME ADI-2 DAC FS, Ferrum Oor with HYPSOS PSU, iFi NEO iDSD and HeadAmp GS-X mini.
The headphones I primarily use with this amp are my Meze Elite, Audeze LCD-X and LCD-5, HIFIMAN Arya Stealth and Focal Utopia. Tonight I plugged in my Audio Technica ATH-ADX5000 for the first time and it sounded superb in tube and tube+ mode with the highest level of gain. I just hope this thing keeps working.
The iFi Pro ICAN Signature is an amazing piece of equipment. The power this amp provides is enough to power any difficult-to-drive headphone or even speakers for that matter. I purchased this amp to drive my HIFIMAN He6se headphones and nothing else I tried had adequate power. This amp provides mind-blowing juice. The sound tailoring features like the x-base just add to the fun. I am hooked on the tube sound, so this is my favorite setting, however there is so much here that anyone can find the sweet spot for their taste. I have tried at least a half dozen different amps for my headphones, and nothing comes close to the iCAN signature. Try as much as you like, but if you want to save time and have a game changer amp for much less than anything that sounds this good, look no further.
If you feel the need to upgrade your headphone or your sound gear you should consider pairing your current DAC/AMP and using it as a DAC and pair it with the iFi Pro iCAN signature. If you look at it as an equation, your current headphone will have better sound in every way shape, and form with your DAC paired with the iFi Pro iCAN signature, than if you were to just upgrade your headphone alone. Amplification is a very detailed and sensitive art in making your sound experience excellent without coloring or adding unnatural garbage. A DAC/AMP Cambo simply doesn't have a decent amp to give your headphone its potential. iFi Pro iCAN signature does this with authority and excellence full stop. Without coloring, iCAN adds better separation, space between instruments, and clarity to everything you listen to. If you can add a stand-alone DAC just like Burson Performace 3X you don't just get to have the cake and eat it too, you get to have the whole Pastry store and its chains and the whole 9 yards on top of that. Let me give you another comparison (Burson comp 3X Performance + iFi Pro iCAN signature) takes my -OEM Samsung Galaxy S10 AKG (free) Earbuds- makes them sound almost as good as an -Audeze LCD 2 close back- running only from iFi Micro iDSD Black Label. I hope this helps. Happy listening.
This is by far the best audio experience I have had with any preamp [and I have used quite a few]. The sound is clear, detailed, and non colored, unless you fiddle around with the doodads using knobs ;). This thing is built like a tank, and equally matched performance too. I have tested it with the following headphones [ranging from economical to premium]: Koss ksc75, Koss porta pro, Koss pro4s, Sennheiser hd [****] Arya gen 1, Hifiman HE6, Sennheiser hd 800s and trust me, there's no disappointment on any of those. You'll be surprised with what pro I can signature can to your headphones. Even Koss ksc75 sounded like some premium headphones. It took the premium stuff to the next level.
I have tested the preamp with the following bookshelf speakers: Adam audio T5V (balanced connection), Monster Clarity HD (balanced connection), Adam Audio A3X + Sub 7 (balanced connection), and B&W 606 s2 + Denon amp (single ended connection), and it brought the best of every single one of these.
If you are curious, I have used it in pairing with ifi idsd diablo, and ifi zen signature dac with Amazon HD music and local flacs as source.
Now on to the doodads: the knobs can fix flaws in your speakers and headphones. They do color the sound, but it's a good color, and better than throwing your gear out of the door. The tubes are voodoo. I don't think I am qualified enough to talk about them.
The wishlist: I wish it had a pentaconn input with xlr.
The only con is that I am sad to find the gold signature badge, and gold trim on the knobs [as shown in the pictures] is not there on the unit. Just the aesthetics though ;)