Egg-Shell Prestige 12WKT

Encore Seven is a typical example of creating and building the brand completely from scratch. The passion, knowledge, experience, and willingness to act were the fundamentals here. In these few words, you can describe the genesis of this manufacture, but we should go back in time 25 years to start the story from the very beginning. As Encore Seven's founders say, the best way to get something good back then was to build it yourself. As teenagers wishing to play the electric guitar, they needed an amplifier, so they used some components from tube receivers and their first amps were created. The owner of the company assured me that, already at this point, his brother came up with the Egg-Shell name and logo, because he dealt with the design of amplifiers for their own needs. In the subsequent years, the passion moved to stereo systems for listening to music at home. Finally, five years ago they started designing new amplifiers and began regular production.

For this purpose, the Encore Seven company was formed. One and a half years later they introduced the first design of an integrated amplifier from the Prestige series. It was an 18-watt push-pull Prestige 18WP model, working in AB class. Paweł Hankus, who was already awarded in the field of industrial furniture design, was responsible for the visual side of the project. That's how the characteristic features of the appearance came into existence. Proportional, low and closed shape with rounded edges, horizontal volume wheel, glass front panel and an unusual V-shaped layout of tubes. After one year, the Prestige 18WP has been replaced with 15WS model. This was the triode, single-ended amp working in pure A class. Simultaneously the less powerful 9WST model appeared, and again after another year the offer has been changed - two MK2 versions and two constructions based on the KT88 tubes - Prestige 20WK and Prestige 10WKT - have been introduced. The latter has been replaced by the new 12WKT model, which is the subject of our review.

On the way, the company released a phono stage compatible with MM cartridges and an unusual remote control. And finally, for the full picture, there is the new Classic series, which is to draw the best technical solutions and visual from the Prestige series at more affordable prices. In this line, only one model is available for now - the Classic 9WLT. The musical passion of the company's founders does not stop at building the amps. It is also music photography, writing the music texts, taking photos during concerts, and even co-organising the contest of music photography. Encore Seven is one of the official patrons of the jazz "City Album" by Michał Wróblewski Trio, which won third place in the poll of Jazz Forum magazine in the Album of the Year category. The company is also the co-founder of the Polish Audio Cluster, uniting manufacturers of high-end audio.

Egg-Shell Prestige 12WKT
All amplifiers from the Prestige line are available in individual finishes.

Design and functionality

A separate paragraph should be devoted to the extraordinary design of the amplifier. Prestige 12WKT is, like the whole series, a very elegant design combined with precise craftsmanship. The amplifier is so distinctive that it is difficult to find something similar on the market, especially at this price. It is simply pretty. We received it in a custom color version - maroon metallic. The manufacturer offers huge number of options for customisation - beginning with the color of the chassis and glass front panel, and ending with the pattern of ventilation holes in the enclosure.

We have quite a lot distinguishing features of the amplifier. Firstly, the Egg-Shell is proportionate and shapely block. Casing components are moved apart a few millimeters, which creates an impression of lightness. In fact, the device weighs 20 kg, due to the transformers' size and solid materials such as metal, glass and MDF. Designing such a slim device probably would not have been possible without V-shaped array of the tubes which reduced the height of the housing. This is clearly associated with high-class motor cars. The inside of the amplifier is made of stainless steel which looks like a mirror. There's a closed chamber for transformers behind the tubes, so the walls of the enclosure reflect the light of tubes, giving the impression as if there were more of them. In the tested model, there were two tubes, but the reflection suggested there were eight of them. The visual impression, especially in the evening, is really very attractive.

Another distinctive feature is a horizontal volume knob. It is huge, although we can see only its fragment. With such a large size, we can precisely set the number of decibels. The knob was finished with paint in the color of the amp and, as the sides, it was made of MDF. The third element is a glass front panel. Because of it, the tubes are visible through the closed construction. For the review, we received the unit with blue glass (green and graphite panels are also available). From the top, the device is is covered with a metal panel with cooling cutouts - here in the form of the extravagant stars. Not everyone may like it, so the manufacturer can deliver the amp with almost any cooling patterns, and simple stripes are offered as standard. Interestingly, the top panel can be easily removed, because it is mounted magnetically. Magnets are strong enough to hold it without any problem. But if someone wanted to expose the tubes, it can be done quickly and without any tools. Clever.

Prestige 12WKT stands on fairly high, oval legs. As the manufacturer assures, this is a way to improve the air flow and cooling. The amplifier heats up quite strongly and we should remove the top panel during long listening sessions. On the back, we find three pairs of line-level inputs. They are gold RCA jacks made by CMC company. The signal for the currently used input is selected by the mechanical knob on the front panel of the device. The number of the selected source is highlighted on the glass panel on the left. Speaker outputs are also gold-plated and they support impedance of 4 and 8 ohms. In addition, on the back we find the power socket and two fuses. You can't see the mains switch here, because it is hidden under the enclosure, on the right. The access is quite convenient because of the high legs. There is also a second switch next to it, which plays a double role. Its first function is the soft start - firstly we turn on the mains switch, then we wait a minute and only after heating the tubes we turn on the second switch, giving high anode voltage to the tubes. From this moment on, the amplifier is ready for use. Turning off looks similar - first we 'drain the current' from the capacitors, and then we turn off the device. The second function of the switch is the stand-by - useful when we have to leave the amplifier for some time but we know that we will resume listening after one hour or so. Useful, but it's a pity that the manufacturer doesn't provide separate LEDs informing when the amplifier is in stand-by mode. Here we get only one LED indicating the amp's activity.

Finally, I have to mention the extravagant remote control. I have to admit that I haven't seen anything like this before. It is a smooth, wooden ball, which has a solid piece of metal at the bottom. The sphere stands on the table, and we simply rotate it to the right or left to change the volume. The remote doesn't have any moving parts, and it's shock-resistant - it simply deactivates when it's struck or knocked over. At the bottom of the ball we can also check the battery status. We also have a switch and mini USB socket for charging the remote control. To see how it works, watch the manufacturer's video on YouTube. Speaking of flaws, I have to mention the lack of markings of the slots for tubes. To make sure which tube should be plugged into which socket, you need to read the instruction manual - every item is clearly marked on the drawing.

Egg-Shell Prestige 12WKT
A unique V-shaped tube layout keeps the amplifier compact and looks brilliant thanks to the glass front panel.

Sound performance

In the first setup the amp worked with NAD C565 BEE CD player, Tara Labs TL-201 interconnect, Triangle Celius ES speakers and Cardas Clear Sky speaker cables. Burn-in soon turned into a normal listening. I started with jazz and rock and Prestige 12WKT played all the tracks completely correctly. Even more - perfectly, as no transistor I've listened to. For a moment, I wondered if I'm really dealing with a tube amp. None of the valve amplifiers I know sounded quite like this. All aspects of tube construction appeared in the jazz music - it was warm, spatial, gentle and transparent. But when I started with rock or heavy metal music, it began to behave like a high-end solid-state amplifier. The bass was tight and free of artificial discoloration. There was also a very good separation between the instruments and proper dynamics, especially where it had to be extreme, for example when the artists were hitting the snare drum. Everything was very well arranged, with no chaos whatsoever.

After such surprise it was time to change the system configuration. Firstly I tried the B&W 803 Diamond - speakers created rather for very powerful transistor amps. The manufacturer declares that the connected amp should have at least 50 W, but here we have only several watts. I started listening to the classical music. The orchestra showed a very big sound. I felt as if my 50 square meter listening room had grown to 200 square meters. The string section, as well as brass section were standing around me. I felt like a conductor who not only listens, but actually manages what, when and where is going to happen. When the bass showed up, I thought that maybe there was a subwoofer somewhere in the room? And it was, but it was turned off this time. In the world of audio equipment, sometimes it pays off to take a chance and go against the manufacturer's advice. The sensitivity of B&W 803 Diamond is 90 dB, which was enough for the Prestige 12WKT to drive speakers properly. Egg-Shell didn't lose its way, but gave me an immense listening pleasure.

This amp is not addressed to a limited group of consumers who are only listening to a couple of jazz albums. It showed every genre faithfully, as per its tube DNA. Its application is constrained only by other elements of a hi-fi system. The Prestige 12WKT performed very well with Triangle Celius ES, B&W 803 Diamond and Bryston Mini A speakers with 87-dB efficiency. This shows how wide is the range of applications for this device, as a universal amplifier and an example of highly neutral tube construction.

Egg-Shell Prestige 12WKT
Power socket, three RCA inputs and speaker terminals for 4 and 8 ohms.

Build quality and technical parameters

Egg-Shell Prestige 12WKT is an integrated single-ended amplifier with a output power of 12 watts per channel in pure class A. It uses KT88 power tubes, one per channel in triode mode. The reviewed unit was equipped with tubes made by Sovtek. The power supply uses one tube - GZ34 JJ double rectifier diode. In the terminology of models, the letter "T" describes the fact that we are dealing with tube power supply. The preamp is the same as in the top model of the company - Prestige 20WK. In each channel, one double triode 6SN7 and one pentode EF86 were used - both made by Electro-Harmonix. The construction doesn't use a feedback loop, and the bias is adapted to the tubes permanently by a resistor cathode. Transformers are and wound by hand in Poland. Thick transformer cores are composed of annealed plaques with a thickness of 0.3 mm, which according to Encore Seven has a positive effect on sound performance and heat. The transformers are mounted on rubber feet isolating them from the chassis in order to reduce vibration. Inside we don't find printed circuit boards - it's a classic, manual construction with point-to-point connections. The device is equipped with Jamicon, Samyoung, and Pilkor capacitors, capable of operating in temperatures up to 105 degrees. With the 4-position input switch, the manufacturer gained complete signal isolation between the selected sockets. The motorized Alps potentiometer is also worth mentioning.

System configuration

NAD C565 BEE, HRT Music Streamer Pro, Norstone Stylum 3, Audio Physic Avanti II, Bowers & Wilkins 803 Diamond, Bryston Mini A, Triangle Celius ES, Accuphase DP-400, Tara Labs TL-201, Cardas Clear Sky, Furutech TP60E, Furutech FP-314Ag, Tellurium Q Black Diamond USB.

Egg-Shell Prestige 12WKT
Horizontal volume wheel is actually very easy to use. The small knob above it is the source selector.


Egg-Shell Prestige 12WKT is a very nice and fully audiophile tube amplifier. Despite rather small output power, it's a very versatile device, so finding right speakers for it is not a difficult task. I was successful with all models I tried - even those that theoretically shouldn't work very well with this amp. The founders of the company put their musical passion in the first place, and it can be seen and heard. I can only hope their efforts will be appreciated by audiophiles all over the world.

There are three base versions of the glass front panel - blue, green and graphite.
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Technical data

Output power: 2 x 12 W
Frequency response: 30 Hz - 20 kHz
Speaker impedance: 4 i 8 ohms
Analogue inputs: 3 x RCA
Tubes: 2 x KT88, 1 x 5AR4, 2 x 6SN7, 2 x EF86
Power consumption: 170 W
Dimensions (H/W/D): 20/40/39 cm
Weight: 20 kg
Price: €2999
Manufacturer: Encore Seven

Sound performance



Editor's rating


StereoLife High End