Sure. The Arcam rHead was such a undervalued headphone amp that I actually had three at one point, in three different audio systems around the house. I sold one a while and up until today, kept two rHeads. It's a Class A headphone amp with average to above-average power. The sound is warm, musical, powerful and instrument separation is good. It takes balanced XLR inputs. Outputs are single-ended 1/4-inch and 3.5mm. It runs warm given that it's Class A and the amp is always primed. It's a budget to midrange amp, but the sound quality is outstanding for the price,
It's been great driving my Beyer T1.2 (600 Ohms) and new Audeze LCD-X (20 Ohms, I think). With the LCD-X in particular, I could sense that the rHead wasn't delivering everything the LCD-X is capable of.
After some research and several questions on here, I bought the Soloist 3XP. The things I was looking for, and things that were slightly missing or subdued in the rHead, were subtlety in particular, and an effortless presentation. By subtlety, it could be hearing more 'breath' of vocalist, a new instrument playing that is so quiet and 'far' that it's difficult to make out with the rHead. By effortless I mean the song is presented with great depth whilst not sounding strained at any time.
I've definitely heard some of these improvements to some degree during an initial listening session today. I'm also able to use the balanced headphone out but I will need to compare it to the single-ended output to see of there's a discernible difference.
Of course, we are talking about diminishing returns when it comes to HiFi, and I'd be a fool for suggesting that I'm hearing night and day differences. The differences are small, but an improvement.
I have a couple of playlists that have songs that I've listened to hundreds of times so I'll be using those playlists over the next few weeks to evaluate the improvements in sounds quality. I've run the Soloist 3XP through a headphone test playlist a couple of times already and it was pretty good.