Desktop headphone amps over the last 5 years have really come a long way. It’s crazy to see how good amps at each price category have become. The Ferrum Oor is a great example of this phenomenon, and it competes with more expensive amps as well. Why do I call it the The Mighty Thor you might ask, because although Oor is not a big as other amps, like Thor is not as big in size compared to some of his contemporaries, hulk for example, the power it possesses is quite impressive for a compact unit, and it competes easily with other bigger amps. Additionally, just like Mjölnir helps Thor reach new heights, the Hypsos does the same for Oor. Now let’s dive into what makes this amp and power supply combo so special.
Build and features:
The build of both units are fantastic, Ferrum definitely machined these units with good precision, and in my opinion they look fantastic. The Hypsos power supply is heavier than the Oor amp, but both units together are not too heavy, so moving them around isn’t an issue, although you’re most likely going to leave it in one place on the desk or rack. The Oor features a knob that you use to switch the amp on and off via RCA or XLR inputs, and also a knob that you use to control the gain. You can also use Oor as a preamp. The Hypsos power supply features a built-in screen. From here you can go to the menu to choose what amp or dac you wish to pair it with and change the voltage output to that device. Overall, build is very nice with a lot of rich features. Now let’s examine the sound portion of this review.
The bass on Ferrum Oor is very tactical and impactful, and it can be quite thunderous when it needs to be. The Oor boasts an impressive 8w at 60 ohms, and I can tell that it is delivering that Mighty Thor power in the bass region which is fantastic. This amp has no issues giving hard to drive headphones like the Hifiman Susvara or Mod House Tungsten the power required to bring the most out of them. Bass has great quantity and control. I enjoy how the Orr can shift gears depending on what’s required. It can go from thunderous bass with great body to very tight and well delineated the next. The bass is also very informative and detailed as well, and I like how Oor can easily position this frequency within the soundstage. With the Hypsos some of these traits are further elevated, but what really stands out to me is that the control of the bass further improves which is a pleasant surprise.
The Midrange on Oor is what I will describe as soulful, but not smoothed over which is important. Although in my opinion I think it has a slightly warmer tilted tonality. It’s not like just because the amp is leaning in that direction that you are missing out on details, which a lot of warmer amps have the tendency to do. Oor just delivers sound in a sweet as honey manner, nothing sounds sterile or sharp in nature, and it’s a joy to listen to. Vocals on this unit sound fantastic, and I like how Oor separates the vocalist from the rest of the mix effectively. Vocals never seem to be overwhelmed, and it’s not too pulled in as far as depth is concerned, which is where the GSX Mini struggled with in this department. Instruments are presented with great tonality and articulation and are very detailed and have great texture. Instrument separation is also superb, and the layering and depth of the midrange is fantastic as well, so it’s very easy for me to decipher the placement of where an instrument should be in the mix. Imaging is also a strong suit of Oor as well, and panning of elements is quite addictive and admirable. If there is one thing I would slightly improve about Oor personally in the midrange department, that would be soundstage size, but that’s just a personal preference thing and not a technical performance issue.
With Hypsos this region improves a little, but mostly transients and control when a song gets energetic, complex, or busy.
Treble on Ferrum Oor is articulate and informative, with a tiny hint of warmth. Although the treble is very and I mean very slightly laid back, I would rather an amp lean in this direction than the other, because in my opinion most headphones will sound pleasant and great with this trait. If you have a Hifiman or Focal headphone, trust me this amp is for you. I really loved the HE1000 series, Arya series, Susvara, Utopia, Stellia, and Clear og with this amp, because any headphone brighter leaning just has great synergy with this amp. Treble detail, control, and articulation is top class, and does not sound sterile or sharp. Information in this region is well separated and very distinguishable and does not sound congested or overbearing. The background information of higher frequencies really stands out as well, and the slightest imperfections of a mix can be easily heard, but it’s not presenting those elements in a forced or grating manner which is a positive. Imaging of higher frequencies is also great, and elements in this region do reach out a little further in the stage, and the depth is generally solid as well. With the Hypsos the added control and separation aids the treble, and in busy passages of a track the extra sense of tactility is always appreciated.
The Ferrum Oor is an amp that honestly, in my testing, works well with a lot of DACs because of its rather neutral non problematic tonality. You can easily run an A26, R26, Ares 2, Pontus, D1se, Spring 3, May, and the Wandla with it no issues at all. It also works well with cheaper DACs as well like a modius which was surprising, but of course you ideally want to supply the Mighty Thor with his proper equipment.
Well as you can see, the Ferrum Oor is a fantastic amp, and it’s a unit I have very little complaints with personally. It’s compact, powerful, great technically, pleasant tonally, engaging, and most importantly very enjoyable. Yes, in my book Oor shares resemblances to the Mighty Thor in so many ways, and when you pair it with the Hypsos it helps it reach new new heights, just like Mjölnir helps Thor reach new levels as well. The Ferrum Oor and Hypsos should be a consideration of yours, if you want a compact stack, that has the power, thunder, and lightning of Thor, and something that can basically do it all in so many regards and aspects.