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Manufacturer: JCAT
Price (when reviewed): 3500 EUR

Contact: JPLAY
ul. Rymarska 45/1
53-206 Wrocław | POLSKA


Provided for the test by: JPLAY


translation Ewa Muszczynko
photos by JCAT, "High Fidelity"

No 233

October 1, 2023

JCAT is a Polish brand established in 2013, owned, along with XACT, by JPLAY. It is run by MARCIN OSTAPOWICZ and focused on "hardware" side of a computer-based music systems. It offers specialized USB and LAN cards, USB and LAN isolators, cables and - above all - power supplies. We test its latest and most expensive product of the latter type, the ULTIMO DC power supply and it is its PREMIERE review.


N 2020, the first external DC power supply, the Optimo 3 Duo model, appeared in the JCAT offer (test → HERE). As Marcin Ostapowicz said in an interview a year later, it was originally conceived as a power supply for USB and NET cards. Later, he and his partner designed a cost-optimized version, but, he added, "based on what we did in a more expensive device" (entire interview → HERE). The Initio, as he referred to it, had one regulator board instead of two and slightly cheaper components than in the more expensive power supply (test → HERE).

Both of these models were created with the custom, line-powered "music” computer in mind. However, they proved to be so successful and versatile that the company decided to make them part of its lineup. The situation is somewhat different with JCAT's latest power supply product, the Ultimo model. Based on its predecessors, it was designed from the outset as a stand-alone product, and a top-of-the-line one at that.


| A few simple words...


ULTIMO LINEAR POWER SUPPLY was developed as a statement type product. It is a completely uncompromising product using the best available technology. It is a demonstration of the engineering capabilities of the team I work with on new products and our sensitivity to sound, as technology is important and provides the foundation for the product, but it is the listening and tuning that leads to the final result. In fact, everything about the OPTIMO 3 DUO, tested earlier by "High Fidelity," holds true for the ULTIMO power supply. However, it is clear that we have made numerous improvements to these designs.

⸜ JAROSŁAW KUPIEC, JCAT’s designer - photo by JCAT.

˻ 1 ˺ Custom-made power transformer according to our design with reduced induction, and minimal dissipation field. Magnetically and electrically shielded. It was designed to operate in the linear part of the magnetic core characteristics and optimized for the lowest possible output impedance. It was filled with resin to minimize mechanical resonances. It was separated from the chassis using high-quality vibration absorbers used in medical equipment.

˻ 2 ˺ Rectifier based on silicon carbide diodes. SiC semiconductor technology features unparalleled properties compared to silicon diodes. Virtually zero turn-off time and negligible oscillations lead to a significant reduction in noise levels compared to standard solid-state rectifiers, which are the main source of the line power supply's inherent noise.

⸜ DC voltage stabilization block

˻ 3 ˺ Three-Stage Topology. Ultimo consists of two regulation stages with a voltage buffer between them. The voltage after the first regulation stage is buffered in a very low impedance stage to improve the dynamic performance of the power supply. It is then fed to the second stage. This configuration provides optimal operating conditions for the output stage, minimizes its thermal load and separates it from low-frequency interference created by rectifying the AC supply voltage. This ensures the highest sound quality.

˻ 4 ˺ Minimal Interference Path. This is a PCB design technique developed by JCAT that optimizes the placement of components responsible for filtering interference as close as possible to its source and with the shortest return path.

˻ 5 ˺ Short and symmetrical current path.

˻ 6 ˺ High-quality, rigid and non-magnetic chassis. Mechanically optimized for best sonic performance, made of high quality anodized aluminum.

˻ 7 ˺ Very high quality workmanship. Best components, PCBs gold plated with 2oz copper. The power supply and all its components are manufactured in Poland.

⸜ DC power cables - older (left) and new (right)

˻ 8 ˺ Cable ULTIMO DC. For our flagship power supply, we designed the best possible DC cable from scratch. I don't want to write too much about it, because we worked on it for a very long time and I'd rather not give away our know-how. I will only say, that the cable is made of OCC copper with a cross-section of 14AWG. It is shielded and has minimized impedance and a special design to minimize mechanical vibrations.

With a power supply of such high quality as the ULTIMO, the use of a top-quality DC cable is key to showing off its capabilities. Using an inferior cable degrades the sound quality greatly. MO.


THE EXTERNAL FORM of the Ultimo power supply is similar to that of the Initio and Optimo 3 Duo power supplies. It features a black aluminum front panel with an orange LED, with the rest of the walls made of bent aluminum sheet. On the back there are one DC voltage output, of the Speakon type, and a Furutech IEC power socket with a fuse from the same company - we no longer have to worry about replacing it with a better one. The unit stands on four feet. These are glued-on rubber parts, which absolutely must be replaced with some real feet in the future. This is because the power supply is very sensitive to vibrations.

The logo on the front panel is milled, rather than painted on. The lettering on the back, on the other hand, is lacquered, except for the indication of what output voltage you get. This information is indicated using a sticker.

Most of the inside is occupied by a large, shielded toroidal transformer with a core flooded with damping material. It was screwed to a metal plate and only the latter is attached to the bottom of the case, but not directly, but through rubber bushings. This part is separated from the rectification and voltage stabilization circuits by an additional shield.

The voltage from the transformer is routed to a circuit board with electronics. At its input is a rectifier based on four discrete diodes covered by a small heat-sink. Behind them was a bank of voltage pre-filtering capacitors. These are eight nice Nichicon high-temperature capacitors of 6800 μF each, designed for audio circuits.

Next is the first voltage stabilization stage, covered by a heat-sink - so you can't see what type it is. However, you can see more ripple suppression capacitors. This time they are even higher quality elements, Nichicon Muse, four pieces of 1000 μF each, and they are accompanied by two Wima polypropylene capacitors, which I assume are connected in parallel with the electrolytic capacitors, smoothing their characteristics for high frequencies. And finally there is a second stabilization stage, also with a heat sink on top.

The cable looks similar to earlier JCAT cables, but has different - I assume better - plugs on the power device side - gold-plated and with a solid aluminum body.

I would like to add that the designer in charge at JCAT is JAROSŁAW KUPIEC, an engineer by training, who worked for many years in the high-tech industry. As Marcin says, he is an avid audiophile and a fan of jazz music.


˻ HOW WE LISTENED ˺ The JCAT Ultimo power supply was tested in a "High Fidelity" reference system, where it was connected to a file player MYTEK BROOKLYN BRIDGE. Mytek has a small built-in switching power supply, purchased by this company from one of its sub-suppliers as a complete circuit.

For comparison, I had the JCAT Optimo 3 Duo power supply, which we bought for our system after its test, and a power supply from Nordost. A separate session was devoted to comparing the Ultimo DC cable and the older cables sold with the Optimo 3 Duo and Initio power supplies.

The JCAT Ultimo power supply stood directly on the top shelf of my rack, namely Finite Elemente Master Reference Pagode Edition MkII on its own feet, next to the Mytek player. It was powered by Harmonix X-DC350M2R Improved-Version cable, alternating with the player. During the test, I listened to music from the Tidal service and files from a USB drive.


⸜ FRANK SINATRA, Come Dance With Me!, Capitol Records/Tidal Master, FLAC MQA Studio 24/192 (1958/2021).
⸜ OSCAR PETERSON TRIO, We Get Request, Verve Records/Tidal Master, FLAC MQA 24/96 (1964/?).
⸜ BENNY CARTER, Jazz Giant, Contemporary Records/Tidal Master, FLAC MQA 24/96 (1958/?).
⸜ TILL BRÖNNER & DIETER ILG, Nightfall, Masterworks/Tidal Master FLAC MQA Studio 24/96 (2018).
⸜ EVA CASSIDY WITH THE LONDON SYMPHONY ORCHESTRA, I Can Only Be Me, Blix Street Records/Tidal Master, FLAC MQA Studio 24/48 (2023).
⸜ JOHN MARTYN, Solid Air (DeLuxe Edition), Island Records/Tidal, FLAC 16/44,1 (1973/2009).
⸜ AROOJ AFTAB, VIJAY IYER, SHAHZAD ISMAILY, Love In Exile,Verve Records/Tidal Master, FLAC MQA 24/96 (2023).
⸜ TEN YEARS AFTER, A Space In Time, Chrysalis | Warner Music Group/Tidal, FLAC 16/44,1 (1971/2014).
⸜ DEPECHE MODE, The Singles 86>98, Mute/Tidal Master, MQA Studio FLAC 16/44,1 (1998/?).

» The recordings featured in the test can be found on a playlist on the streaming service TIDAL → HERE .


THE CHANGES INTRODUCED BY different types of DC power supplies, well, differ from case to case. Small, large, important and less important, impressive and indifferent. But always - there are some. In the case of the Mytek Brooklyn Bridge player, which I tried the Ultimo with, they go in the direction of cleaning and deepening the sound at the same time. Sometimes, with the best power supplies they do more than that: they change the way you listen to music. The Ultimo does the same thing, in which it closely resembles the Ferrum Hypsos power supply.

This relies on the fact that if the band accompanying FRANK SINATRA on the album Come Dance With Me! is perceived in a somewhat bright and emphatic way, the tested power supply modifies it. We are still dealing with strong performance, emphasized by the extreme distribution of the band across the channels. Now, however, it is sounding much smoother and - let’s say - silky. It's the "silkiness" of the brass, to be clear, but so different from the metallic sound that Mytek itself serves up that it's hard to believe.

And now - I slightly exaggerated the metallicity. Mytek powered by AC cable is open and accurate, but never harsh. However, comparing its sound "with'' and "without'' the power supply, we have this very impression, as if the Ultimo removed the hard component from the attack and replaced it with velvet. It's still powerful playing, but now much more humane, just musically better. And that's because instead of one sound we have two, instead of two we have four, etc. The power supply brings out its components from a similar-sounding cluster.

It might seem that the presentation is turned warm by this. And it is, a little bit. We perceive this "new" sound because it's different enough from the "old" one, as if everything is rounder and more saturated. But with all this, the tested power supply goes in the direction of better instrument separation, or rather in the direction of their better selectivity. Although warming is usually associated with a fusion of layers and sources, with the Ultimo it is different. Both Sinatra's vocals and then OSCAR PETERSON's trio were presented in a more accurate way, giving a larger sound picture with better selectivity.

This was repeated, moreover, with BENNY CARTER's Jazz Giant. The leader's alto saxophone and Ben Webster's tenor saxophone (BTW, having recently been in Copenhagen, I learned that he rests at a local cemetery), placed in the left channel had distinctly separate "spaces" despite being on the same axis after all. Anyway, Carter's trumpet, which enters later - we're talking about the track Old Fashioned Love - was given its own axis. In this recording, unlike the previous two, we have only the left channel and only the right channel. A difficult thing to reproduce, but if it's done correctly, as with Ultimo, giving very satisfying results.

Because it was big playing with clear sources, that almost jumped out of the speakers. Without an external power supply, the Mytek played this album very well, with dynamics, spark, drive, or whatever you want to call it. But the JCAT added so much intensity to all these elements, and calmed everything down at the same time, that it was something else entirely.

I've already noticed this with Sinatra, it was nicely demonstrated on the Carter album, but it came out perfectly on the TILL BRÖNNER & DIETER ILG duo album. Ilg's double bass with the power supply played in a stronger way. And, interestingly, the Ultimo showed that it was recorded a little too offensively, sacrificing some body and subtlety in the name of clarity and mass. It's an excellent album, a great recording, and everyone would wish such albums at home. But, just like any other one, it is a collection of compromises.

And this one, that is, emphasizing the beat to fill the space between the speakers, is one of them. This is usually achieved by recording the instrument directly from the microphone and simultaneously through the guitar amp or from a pick-up taped to the body. In this case, we could clearly hear that the direct microphone was a secondary sound source. So in the end, the recording of A Thousen Kisses Deep, a cover of a Leonard Cohen song, had a distinct sound, and indeed the double bass filled the space in front of me. But now I understood better that this was not an entirely "faithful" recording of the instrument, in the sense that artistic considerations forced sound choices.

I was able to convince myself that this is not the power supply's own sonic signature, but rather its effect on the device it is powering, giving it more freedom to interpret the musical signal, while listening to Autumn Leaves (Instrumental) from EVA CASSIDY's I Can Only Be Me album. Her vocals have been admixed to the sound of the orchestra and are quite bright - a feature of most of her recordings, by the way. Without an external power supply, the Mytek reproduced this recording in a smooth, nice way without forgetting the brightening I'm talking about. With the Ultimo plugged in, the brightness remained, but there were slightly less muffled elements in her voice, resulting from the recording itself and the microphone she was using. It was as if the JCAT had cleaned it up slightly.

This was a different performance than what the Ferrum power supply did. Hypsos went in the direction of darker sound, even at the expense of less detail. The JCAT, on the other hand, allowed Mytek to play more clearly, stronger. It's a similar level of quality, very high, although the effect achieved was different. Ultimo goes in the direction of enlarging dynamics, selectivity and bass. It gently pushes back the foreground, as recordings have more breath. But it doesn't round off the attack or warm up the sound in the way that most turntables do, for example.

JOHN MARTYN's track Solid Air was thus shown a bit further away than without the JCAT power supply, but the accompanying reverb was just as bright, and the guitar strings, although it is, it seems, a classical guitar and therefore with nylon strings, were crisp. Nothing was muffled or covered up in the midrange. Because the Ultimo, we finally come to it, widens the frequency response, adding energy at the band's extremes. Without it, the Mytek played them in a somewhat dirty way. That is, it masked them and lost energy there. The tested power supply largely restored them both.

And at the same time everything was more sonorous and pretty. Yes - pretty. While that's a vague definition, it captures well what Ultimo brings to the system. Because both TEN YEARS AFTER with A Space In Time, and DEPECHE MODE with the track Behind The Wheel, originally included on the Music For The Masses album and played by me from the compilation titled The Singles 86>98, as well as the previously referenced tracks, they all just sounded better. Precisely because the sound seemed nicer with it.

˻ DC CABLES ˺ Along with the new Ultimo power supply, we also get a new DC power cable. So comparing it with the older one seemed to me an important part of the test.

And...? - And, it seems, some of the changes in tonality I mentioned are results of using this cable. The power supply offers dynamics, resolution and energy, but it's the cable that allows the bandwidth to expand. The older DC cable listened to with the JCAT lowered the timbre and saturated the low midrange more strongly. The remarkable resolution of the band's extremes disappeared, and the midrange also got a bit foggy. However, it may be worth trying this combination at home as well, since some may find such a high amount of information undesirable.

The new cable gives a more accurate picture of the instruments. Ray Brown's double bass from the Peterson’s album had a less pronounced attack, and the leader's piano lost some of its luster. These were not major changes, ultimately the biggest change was obtained by adding the power supply to the Mytek. But they were there, and in a well-tuned system you will be able to determine for yourself what is more important to you.


ULTIMO DOES WHAT WE WANT when we equip a device with a high-end power supply. It cleans the sound of „dirt”, widens the frequency response and energizes the presentation. It's a power supply that doesn't hide anything under warming, nor does it change the tonality of recordings - it's exceptionally true to their sound. It also gives them breath and deepens the soundstage. Because the latter also benefits a lot from having more low-level information in the signal.

Bass is strong, dense and extremely dynamic with it. With the Ultimo it takes on clarity - whether it's a double bass or a guitar amp, or - if it's bass generated from a synthesizer - it shows more of its shades. Everything with it takes shape, literally. Even such ethereal playing as that from AROOJA AFTABA's Love In Exile album (nota bene - a beautiful album) takes on mass, and meaning with it.

Because the JCAT Ultimo is an exceptionally good product. It is also different enough in what it does from other power supplies that it will be easy to decide if this is what you are looking for.


THIS TEST HAS BEEN PROVIDED UNDER THE GUIDELINES adopted by the Association of International Audiophile Publications, an international audio press association concerned with ethical and professional standards in our industry; HIGH FIDELITY is a founding member. You can find more about the association and its constituent titles HERE .


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