Børresen Z1 Cryo Loudspeakers | REVIEW

Børresen z1 cryo

Did I get those speakers in for review? You know, the little monitors that cost $100,000 per pair, the ones that baffled me with their impossibly epic sound and subsequently prompted my adventure in Denmark this past summer to determine if they were, indeed, legit? I did not get those speakers, the Børresen M1s, in for review–at the time of my visit to the factory in Aalborg last August there were only two pairs in the world, and one of them was completely disassembled on a table in front of me so I could see its innards. No, I’ll be reviewing the Børresen Z1 Cryo monitors instead.

The Børresen Z1 Cryo monitors, which sell for $14,500 per pair USD, are located nearer to the beginning of the bookshelf speaker line–still an exceptionally lofty place to be. (Throw in an extra $2,860 for the very cool dedicated stands, which I’ll describe in a bit.) The actual entry-level monitor for Børresen is the $12,000 per pair Z1s, which come without the cryogenic treatment at the Audio Group Denmark factory. I’ve seen that vat in person, and I was close enough to be told to be careful and to step back.

Words and Photos by Marc Phillips

During this visit, I participated in numerous A/B comparisons between the Børresen Z1 monitors, Cryo vs. non-Cryo versions–in fact, I did this for nearly every other model in the Børresen line-up. Depending upon the specific upgrades between models, such as driver complement and materials, I heard steady improvements in clarity and a stunningly low noise floor as I moved up. When I compared the two Z1s, the differences in sound were not subtle. An additional layer of detail was added with the Børresen Z1 Cryo, but there was a more of an organic improvement in the sound.

In my article on the AGD factory, I mentioned that these differences felt like I had watched a painter create a beautiful portrait and then go back because he forgot to add a certain color. (For some reason Colleen and I have been binging on Bob Ross lately.) You didn’t notice the color was missing of course, until you observed how the whole was taken to the next level. If you’re not quite sold on the benefits of cryogenics in the high-end audio industry, here’s a fantastic and clear introduction. Grab a seat and listen for yourself. Don’t formulate an opinion until you do.

marc phillips system

Inside the Børresen Z1 Cryos

When Audio Group Denmark says the Børresen Z1 Cryos have been treated in a cryogenic chamber for 72 hours, they’re talking about all the metal components being placed in that scary frozen vat at the Aalborg factory. One notable exception is the Børresen planar ribbon tweeter–that ultra-thin membrane doesn’t quite stand up to absolute zero. But everything else metallic does spend time in the cooler, so to speak.

I get your hesitation. When it comes to high-end audio, cryogenics is still one of those proven technologies that foster endless snarky comments on internet discussion forums, usually with an unnecessary and problematic Walt Disney reference thrown in. The science, however, is solid. I’m familiar with cryogenically treated cables, having used Furutech’s flagship loom for almost a dozen years now, and I’ve read huge chunks of their research on the technology. This Japanese company has published most of their findings on the subject, including detailed microscopic images of how the crystal structures in copper re-align after freezing, which allows a “pure(r) transmission” of the signal, to paraphrase Furutech’s tag line.

audio group denmark

At Audio Group Denmark, Michael Børresen adds a new wrinkle to the cryogenics discussion–the treatment also lowers inductance, something that can be easily measured. It’s one more tool in the toolbox when it comes to achieving AGD’s primary goal of eliminating noise from the audio system. But the more common benefit of cryogenics, as explored earlier by Furutech, concerns conductivity. Or, in the words of Audio Group Denmark:

“Cryogenic treatment of all metal components of the loudspeaker results in a further significant improvement in conductivity – unleashing finest and most subtle musical details. When metal components undergo cryogenic processing, they are subjected to extreme cooling. In the wake of this process, the crystal structure of the metal contracts more and more. Alloying elements are pushed out of the grain structure of the metal, which now becomes very similar to a monocrystal. These structural changes in the metal have a profound effect on its audio properties, resulting in an increase of conductivity by 6-8%.”

If you’re still doubting the effects of cryogenic treatments, you can simply come to Aalborg and compare the Børresen Z1 to the Z1 Cryo–as I’ve already suggested. If you’re still skeptical, I suggest you head over to the company’s pub where Lars Kristensen will make you the best gin and tonic you’ve ever had, made with cryogenically treated gin.

I disliked gin until that fateful day. Cryogenics, it seems, makes everything better.

making cone membranes

Beyond the cryo, the frozen version of the Børresen Z1s still offer plenty of unusual, cutting edge technology. Both drivers, of course, are made from scratch in the factory–I seen ’em do it. We’re talking, of course, about the classic Børresen planar ribbon tweeter and 4.5″ Børresen bass/midrange driver. Here’s the technical scoop on the bass midrange driver:

“The Børresen membrane consists of a composite of two layers of very thin carbon on both sides of a 4 mm Nomex honeycomb core. This composite structure – like the one used in formula 1 type of racing cars – provides the ultimate combination of stiffness to weight ratio. The exceptionally low weight of only 5.5 grams allows a very high acceleration factor in the driver, resulting in both outstanding resolution and higher efficiency.”

And the tweeter:

“The efficiency of this closed ribbon tweeter amounts to an exceptional 94dB and operates from approximately 2.5 kHz upwards. The moving mass is extremely low at 0.01 grams. The totally concealed tweeter has the capacity to operate at an incredible speed, which is an absolute prerequisite to unlocking the most subtle and refined sound details of any kind of music. The enormous robustness of this tweeter allows it to handle extremely high transient peaks without any ear fatiguing breakups. No transformers are being used.”

The specs on this two-way bookshelf monitor don’t tell an unusual story–the 50Hz-50kHz frequency response spec does not account for the fullness of the Z1’s sound, which of course is transformed when you use the side walls to reinforce the lowest octaves. Sensitivity is 86 dB, with a 6-ohm impedance, which also seems less meaningful when you consider three of Aavik’s integrated amplifiers are class D and provide 300 wpc.

But when you dive into this speaker, you notice details such as the parallel crossover, which is built to be mechanically stable to reduce any resonance these parts can create, and the driver magnets, which borrow technology from the iron-free driver assemblies in the O series from Børresen to lower inductance to one-tenth of the amount in conventional drivers. You also get an enclosure made from the same composite material AGD has developed to further reduce noise and resonances. The knuckle rap test revealed a very solid and acoustically dead box.

As I mentioned, the specs seem altogether unimportant after spending months with the Børresen Z1 Cryos in the system and hearing just how athletic and capable these monitors are.

Børresen z1 cryo


I knew this was going to be my biggest challenge with the Børresen Z1 Cryos, that they require unconventional placement in the room to achieve their potential. Everyone at AGD mentioned the Børresens’ preference for loading along the side walls, and the whole time I’m sitting there nodding and thinking oh man, I have to completely rearrange my listening space to accomplish this. I should get used to this, since I’m getting some Audio Note UK speakers in for review later this year.

This goes back to my very first exposure to the Børresen M1s back in Munich, and how Lars Kristensen had them placed far out into the room, and tight against the side walls, which bolstered the bass response and created an incredibly wide soundstage thanks to the good 20 to 25 feet of distance between them. Could I do that if I needed to? If I place the Børresen Z1 Cryos where all the other two-way monitors usually wind up and the result is dreadful, will I have the common decency to admit I was wrong and then listen to those who know their speakers better than I do?

Well, at least I had to try the Børresen Z1 Cryos in my conventional preference just to see how wrong I was. I have to admit, the Z1 Cryos made an immediate big splash within the first couple of songs, with plenty of size and weight and balance to the overall presentation. The solid low frequency performance tapped my shoulder almost immediately, confirming it was there and ready for its close-up whenever I had the gumption to play something that really jammed. We’ll come back to this in a bit.

The Børresen Z1 Cryos spent most of their time with the rest of the Audio Group Denmark products I’ve received, revolving around the Aavik U-280 integrated amplifier/DAC and S-280 digital streamer, with Ansuz cabling, power distribution and ethernet switch. The Z1s also hung around after class so I could listen to them with non-AGD products such as the Burmester 101 integrated amplifier and the Musical Fidelity M8S PRE preamplifier/Ayre V-3 combo.

dedicated stands

Børresen Z1 Speaker Stands

I really enjoyed the dedicated stands for the Børresen Z1 Cryo–this is a manufacturer that clearly doesn’t scrimp on anything, and it’s clear that same unconventional and limitless thinking applies here. First of all, the stands are light since they’re made from that same composite material you’ll find throughout the company’s three brands. The Z1s are solid and substantial but not incredibly heavy (both stand and speaker weigh just short of 40 pounds), so it’s very easy to slide the speakers around on their stands for optimal placement.

They’re even easy to assemble, with big composite screws that are meant to be tightened with a coin. The final touch is the four ball bearings that fit into little cups at the four corners of the top plate. You place the bearings in the cups, place the Z1s on top (the speakers have cups on the bottom as well), and then you install one of those big screws underneath and tighten it all down.


The unusual part about these stands is that the entire structure is somewhat flexible–it’s easy to get the speakers to sway side to side. At first this seemed a little unstable, but it’s not. It’s just one more way of decoupling the speakers from the floor. I’ve dealt with precarious speaker stand arrangements many times, and this is not one of them.

The Børresen Monitor Z stands are not cheap at $2,860/pr USD, especially since they’re light enough to chuck across your front lawn like a javelin, but they are elegant and effective. Børresen even makes a more ambitious stand for the 01 two-way monitors, and those cost $5,500/pr. They’re the ones you’ll usually see under the $100,000/pr M1s.

Børresen Z1 Cryo


The Børresen Z1 Cryo loudspeakers went high. They went low. They went deep. They went wide. They went tall.

I’ll hazard a guess and say there’s a correlation between a low noise floor and the ability of a small loudspeaker like this to utterly disappear in the room. Noise and other types of artificial presences can ground the images within the narrow confines of the soundstage. The Z1s had a way of cutting those tethers and allowing music to exist in a larger three-dimensional space–here, there and everywhere. Soundstage depth and width was formidable.

I often heard sounds flanking my listening position, which inspired me to listen to tracks such as “Dogs,” from the newly reissued Animals from Pink Floyd (who put a big hound dog out on my balcony?) and that memorable horse-drawn sleigh in “Too Much Rope” from Rogers Waters’ Amused to Death, which miraculously travels from ten o’clock to four o’clock in your listening space if it’s done right.

How did the unorthodox speaker positioning work out for the Børresen Z1 Cryos? In my usual speaker position, which is 2-3′ from the rear, along the long wall of the room with very little side room reinforcement, I still heard deep bass that was very cooperative with my listening room with a superb and linear balance up and down the frequency range. It wasn’t too much bass (I’m still surprised at that 50 Hz spec), which tends to excite nodes in this room, but there was a calmness and poise to the Z1’s deepest bass performance that convinced me that I had all I ever needed.

So why even bother trying out Michael Børresen’s preferred way of using the side walls for low frequency reinforcement? I keep thinking of the Børresen testing room at the factory, where there was plenty of space between the speakers but the side walls didn’t seem to be that close. But I also think of the Børresen M1s at Munich and Seattle, and how they were brought halfway into the room, along the side walls. That’s what got me started on the whole adventure, after all.

Since I’ve set-up my room to be extremely flexible when it comes to speaker placement–there’s plenty of space to slide things around to accommodate special requests, I went ahead and rotated the entire room. Once the Børresen Z1 Cryos found their new home, I sat down for a listen.

The Z1s went from being a solid and competitive premium two-way bookshelf monitor to something much closer to the M1. All of my favorable first impressions of the Børresen Z1 Cryos were suddenly and unexpectedly enhanced. The overall dimensions of the soundstage expanded even more than I thought possible, the deepest bass stretched its legs out and relaxed, and I heard even more detail than before because the map of the landscape was now more encompassing. Only the already superb and natural tonality was left unchanged.

So yes, put them close to the side walls if you can.

Børresen Z1 Cryo


I listened to the Børresen Z1 Cryos in my system for a few months without interruption, which means I listened to a lot of music through them and it’s hard to trot out a giant list. But I will tell you about a specific magic moment.

I finally had all of the Audio Group Denmark pieces in place–it took me a little while to integrate the Aavik S-280 digital streamer into the system and figure out all its secrets. When the music finally flowed from Qobuz for the first time, I was knocked for a loop. I’d been trying to cue up the new Fred Hersch just because I dig the way his piano sounds like no one else’s, and the sound quality on his albums is always superb. What I didn’t know in advance was the new album is a duet with the amazing Esperanza Spalding, Alive at the Village Vanguard, and when her voice finally appeared after a few minutes of Fred Hersch, it was so immediate that it startled me.

Fred and Esperanza were two distinct forces, separated by some distance but still together in the same room/stage. The full Audio Group Denmark system was so exacting, so meticulous in its rendering of the tiniest details, that you can clearly see that dividing line between the dual origin of these sounds and they way they meet in the middle and draw energy from each other. We audiophiles like to proclaim that the finest audio systems can make you feel as if the performers are really in the room, but this almost seems like an extra step toward reality. You can almost see the two performers looking at each other for clues, suggestions and affirmations. It’s a mesmerizing way to experience music.

Børresen Z1 Cryo

Børresen Z1 Cryo Conclusions

To tell you the truth, I was a little relieved that Audio Group Denmark didn’t send me the Børresen M1s at first. A pair of small two-way monitors that retail for six figures? I’d have to put velvet ropes around them and listen with my dad’s old Winchester sitting across my lap. (But if they offered them to me, heck yeah.) I think the Børresen Z1 Cryos are more in my wheelhouse–these are competitively priced among my bookshelf faves, so I have a much stronger sense of what they should be doing at this price point.

Nevertheless, the Børresen Z1 Cryos distinguished themselves among those premium monitors I tend to champion by fulfilling their role in an Aavik and Ansuz system, which is delivering low distortion, low noise, stunning black backgrounds and thrilling me endlessly at the frequency extremes. In many ways the Børresens are one of those exceptionally clean and transparent monitors that let you hear deep into the recording–like studio monitors. Yes, they’re neutral. Exceptionally so. But that didn’t sound like I thought it was going to sound.

I keep repeating this mantra about lower noise floors and their gift of delivering more music to your ears. That doesn’t mean the Børresen Z1 Cryos are cold or uninvolving or sterile or overly detailed. When you hear everything that is on a recording, that includes much of the human presence that’s associated with the making of music. You don’t just hear music, you hear human beings making that music. That gives the music a more immediate and natural feel. “Neutrality” becomes secondary, of course, to being a part of the musical event. Nothing feels forced.

While I’ve heard a few bookshelf speakers over the years that accomplish this type of performance, none do it with this same level of effortlessness. Highly recommended.

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audio group denmark

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Børresen Z1 Cryo

Børresen Z1 Cryo

cryogenic gin