Ferrum OOR / HYPSOS Headamp Review: Girl You Know It's True

Yannow what, I'm gonna throw a winky dinky devil's advocate argument out for the sake of it and say that shielding the transformer will negatively affect the performance of said transformer. All those magnetic fields and crap have to radiate for their mojo to work properly and squishing/constraining them will make the heisenburgs flow in counter capacitivity and make angry onomatopoeia noises.

 

I think my boss put it succinctly, with a 1 year return policy, it doesn't serve us if we sell a bad product to a customer if they end up returning it anyway. Even when I was on commission at TSAV, I would rather take that hit on commission selling a cheaper product that worked better for the person than the more pricey crap that wouldn't.

Oor and Hypsos is rather interesting to me still, beginning of Ferrum brand there was the hype that the Oor was the Susvara amp to grab since its like half the price of amps with similar performance, standard FOMO in the beginning. As time passed the hype did cool down and it was now moving more on its own when they came out with Erco and Wandla especially. Still will have folks get the Oor+Hypsos blind and end up only wanting to return Oor for the sound not synergizing with their system... But they love the Hypsos and want to keep that.

The guys behind the brand are cool folks and I like the NA distributor. The brand is still relatively new and I would be interested to see what they got cooking for the future. Back when I was at Questyle I liked how our products were all generally the same size for desktop stuff but now I also see how that was rather limiting. Ferrum everything is the same size and if they could break that mold, I wonder what their team could cook up without restriction.

 

I'd really prefer not to have to murder you tomorrow.

 

That last measurement is a pretty good punchline. I mean, they're obviously intended to stack given all the photos of the stuff stacking. Everything else aside, it's really bad to have the thousand dollar power supply cause measurable power fuckery when deployed as advertised.

Something else this makes me think of, is a lot of headphone amps seem to get reviewed as do-all generalists by some people, and dead/boring by others. I've seen that with this, Liquid Platinum, a few others. Which I guess makes me wonder whether 1. some people (probably me included, honestly... at least sometimes) really are looking for a very nice version of sleepy sound, and 2. whether a lot of those amps actually do have something they work well with, and the people reviewing just didn't have that kind of headphone on hand.

 

I haven't heard the Oor extensively, but I will say that for the same $ there are other amps I preferred planars - sadly some were DIY, some I don't remember the name of, and some are OOP.

Also what YMO said - I can get MOT or some other people in some situations not wanting to say when they don't like something... but lack of any dissenting opinions here is not going to be good for this place long term.
That and 90% of the times I enjoy being this guy when people debate here:

 

So @penguins just want to eat or smoke while seeing a bitch fight. That’s the summary of what I got from it.

 

transformer hum due to constipated heisenburgs:

 

That reminds me, I should pack a couple of my fancy knives for the meet...

 

My birthday actually falls on Groundhog day (Feb 2 every single year), weirdly enough.

 

So I had this in my notes when I first heard OOR 2 years ago at a show: "I would put it alongside Headamp's GSX-2 in terms of broad overall quality but OOR is a bit warmer sounding and not as powerful. For the size OOR stack is great, but overpriced." I think I did pretty good for a 20min show demo

Forgot to add, I think the dealer at the time had the amp and PSU side by side and not stacked.

 

I think the size aspect is really underappreciated here, there's a lot of headphone amps on the market that can't be classified as desktop gear anymore because the boxes are massive, weigh a ton and output so much heat that siting in front of them gets uncomfortable after a few hours. I'm not saying all amps should be like that but it's nice to see an amp that's not carsized for a change.

 

I am of the opinion that if it fits on my desk, it's a desktop I have 2 CFA3s and those are for sure desktop amps

Yeah, OOR's size is definitely a plus for folks with limited desktop space.

 

There is much to be said of solid state technology. It has allowed for much of our advancement in the past 70 years. You would think we would have a simple hi-fi amplifier for headphones figured out by now.

The tech? Let’s look at their white paper:

"First of all OOR has unique discrete output stage. It is not class A, it is rather something between class A and AB. OOR doesn’t have full-time operational current source, which forces the current through one transistor, which always deliver current to load. Instead it has special circuitry, which never lets to turn off neither of both output steering transistors, which are polarised similarly as in class AB. It is done in a way, that current of both transistors is monitored by independent circuits and those circuits prevents to drop below some threshold value of current. That way the distortion is much lower, because the transistors aren’t going through the most nonlinear region of its characteristic. This output stage is even more linearised by feedback loop of discrete current feedback amplifier, which has about 60kHz of open loop bandwidth (-3dB) and almost 1MHz of closed loop bandwidth (-3dB). 60kHz of open loop bandwidth was achievable due to two-pole compensation scheme. This feature makes distortion more flat in audio spectrum, because the open loop gain rolls off at higher frequencies compared to typical Miller compensation. This wide open loop bandwidth is not present in IC headphone amplifiers." ​

Ok…so I actually understand MOST of that. It still looks like a few key words…discrete current feedback…wide open loop bandwidth. And the topology is “somewhere between class A and AB.” Let’s just take their word for it.

Now, before anyone reads further and wants to get knives out, just understand the only orthodynamic headphones I own are legendary Audeze LCD-2, which are only moderately hard to drive. I wish I had something like Susvara or LCD-R, but alas. It is what I have. I jumped on the loaner before really doing my research.

Soundwise, this is a rather boring amp. It does have good blackground and some width. It does not sound laid back or soft nor does it sound overly aggressive. No real tube like qualities, it is very fast solid state. It is very neutral in sound presentation. The attacks and leading edge are there without being too much. The mids still could a bit harsh and grainy. It makes the amp have a more forward presentation.

I just feel there is not really good layering with the Orr. I can get WAY better layering out of my MJ2 and things don’t get in the way. The depth of things and instruments not having enough space around them, especially when things get complex. I like to listen to music like I am behind the console and isolate every instrument because every instrument should have its own space. When the track gets thick, complicated, every track is compressed, the staging just goes flat and the sound gets even a bit more mid-centric. The amp no longer sounds open and effortless. Not as bad as some other amps I have heard do this (eg. Jot 2), but it is still there. Maybe this is just me being super sensitive to this with current feedback designs, but just feel like there is a loss of both micro and macro dynamics, and then eventually everything sounds like that.

There was mention of the Liquid Gold, and I did hear the Monoprice version that went around with the RD-X and from memory I will say the Liquid Gold had even more background, better dynamics, and way better layering. The mids on the LAuX are more relaxed and it sounded like a never ending soundscape. It is a much more different experience amp that is nearly the perfect amp for orthodynamics. I don’t know why anyone would call that amp boring, but it is slightly darker tilted, but one of the more effortless amps I have ever heard.

Someone also mentioned something like the Magi Unity. The Orr is much more smoother in the mids and slightly more of a refined amp than Unity. Albeit, this is only with orthodynamics. Although I can see the argument over Unity because it is something that works fairly well with more variety of sources and headphones. Orr might have a little liquidity, and smoothness, but not much. With the price, it should be winning way more categories.

Like I said, I know this amp is likely more for headphones that demand more power, but I don’t think that is going to totally change the personality of the amp. It sounds way more polite than the amp power suggests and in the end did not have any kind of “wow” factor.

 

Ferrum Oor & Hypsos Loaner Impressions

Thank you SBAF and Julie for making this loaner tour possible, I very much appreciate the great opportunities to audition gear at home and gain valuable first-hand experience with so many things I’d not otherwise get to try.

Unfortunately, listening to the Ferrum stack was less a pleasurable experience and more an exercise in diagnosing audio maladies. I wonder if this stack is defective – more rust than iron? Alternatively, and I should emphasize this, I wonder if I screwed up. EDIT: please disregard the text here and below that I'm striking through today 1/18/24: I may have had the Hypsos configured incorrectly and not set to the correct voltage for the Oor. I think I was outputting 14v to the Oor but it might have been 24v. I forget. Sorry. Please bear this in mind as you read the following impressions. It turns out that I did have the Hypsos set up correctly, outputting 24v, to the Oor, as @Ksaurav402 noted here).


Gear
I tried the Oor and Hypsos in a chain with my Yggdrasil A2 and Atrium and LCD-4 headphones. The Atrium has the solid mesh installed, for a darker tuning, and I tried the LCD-4 in its stock form, i.e. with no EQ as well as with the Audeze Reveal present EQ, and a modified version of the Oratory EQ profile (reducing the mid-bass hump and the upper-mid emphasis to make it less like a Harmon target), all in a vain effort to get the headphones to sound half-way decent from this amp.

I tried both headphones with medium and high gain. The Atrium sounded better – more open and lighter in tonality, less compressed and ponderous – from the high gain. The LCD-4 was poor from both settings.


Other Caveat
I also got to hear the Oor back in November, at a friend’s place after a day spent at CAF. I really liked it. I was tired, though, from a day spent listening intently to a bunch of 2-channel setups. I had a headache, wasn’t in the quietest environment, and only heard the Oor with my LCD-4 for a couple of tracks and with an unfamiliar DAC. I don’t remember it sounding so bad as this loaner unit.


Strike 1
The Ferrum stack made the LCD-4 super fatiguing. This was less the case with the Atrium. But both suffered from some kind of treble trouble. I wondered if the stock tuning of the LCD-4 contributed to this problem: it has the treble emphasis that bothered Tyll Hertsens and that makes for an incoherent transition from the mids through the treble. The two EQ settings did nothing to ameliorate the treble issues, so I’m not sure what’s going on.

Adding to my troubleshooting trouble was the unclear reason why I found the pairing so fatiguing. It had something to do with the upper registers, I think, but I couldn’t hear any specific peaks. Maybe the combination is jagged and uneven in the treble? The treble didn’t seem to suffer from grain or etch. I did hear some ringing in the treble on Radiohead’s Decks Dark.

It got to the point where I couldn’t tolerate the LCD-4 for long at all. The LCD-4 has its tuning oddities, to be sure, but I’ve never found it to be fatiguing before.


Strike 2
The Oor made both headphones sound compressed and congested. Separation is really poor. There’s a suffocating lack of space and air around instruments. I wonder if the wrong voltage from the Hypsos explains this.


Strike 3
As I had it set up, the Oor was the definition of limp dick. No impact. No slam. Poor macrodynamic contrast. The LCD-4’s not the most percussive headphone at the best of times. But the Atrium can hit like a freight train. With the Oor, it hit like a slow-moving marshmallow. Again, I wonder if this would be a sign of the Hypsos not putting out enough voltage.


Game Over
The final straw, and the single worst offense, was what the Ferrum stack did to overtones. They were almost completely missing. I could barely recognize acoustic guitars for what they are. They were like synthesized approximations. Without being able to make out harmonics, there was no sparkle, and the complexity of the instrument was entirely missing. So weirdly bad was it that it sounded like I had a really crap DAC in my chain. (I double checked, the Yggdrasil’s fine). Would the Hypsos on the wrong setting account for this?

I suspect a consequence of the lack of overtones was the weird sound of reverberations. I listened to a Shostakovich string quartet and all the instruments were too smooth. The problem was more apparent with electric instruments. I use PJ Harvey’s Meet Ze Monsta to listen for bass and electric guitar textures. Both are distorted on this song, and the guitar has a great growling, crunchy, and tactile sound. With the Oor, all of this was missing. The same thing could be said for The Oh Sees track Sticky Hulks.


Other troubles
Transient attacks were slightly rounded, which, combined with the other problems, made for a plodding, lethargic sound. The LCD-4, not the fastest of headphones to begin with, sounded like molasses. The Atrium suffered less. But the sound was still ploddingly slow.


Conclusion
I tend to be more circumspect in my impressions than I have been here, and I again need to note that I may have screwed up with the Hypsos settings. But if I didn’t, the Oor was awful, probably the worst amp I’ve heard. If this unit isn’t broken, and if the Hypsos settings don’t account for the problems, then it’d be absolutely shocking for these items to be sold for $3000+.

Lesson learned: I should have persevered and experimented more. The sound was so unpleasant, though, that I didn’t want to listen to music for any more than the two nights I spent with the Ferrum stack.

 

Hum... The spec voltage for Oor is 24V. As for the unit(s) being potentially faulty: I had to get my Hypsos replaced (excessive transformer hum), and the Oor is annoyingly sensitive to static, I've had it get into weird states if I stand up suddenly from a fabric-covered sofa while listening.

Having said all that, lack of space around instruments is the last thing I'd say about this amp (with Caldera or Atrium). Really wondering if the unit(s) in the tour are messed up.

 

FWIW, this matches exactly every experience I’ve had with the Oor+Hypsos. The first time I heard it I was blasted back into 2009 because it sounded almost exactly like an Objective2 to me.

If it isn’t supposed to be like this I’d be a lot more interested since I love the aesthetics, but I’ve seen a few owners of the combo describe it as “better THX” which makes me think that’s just how it’s supposed to be.