Margules U-280 SC. 30th Anniversary Limited Edition




This amplifier incorporates our proprietary Active Servo Bias, which guarantees an optimal operation since it does not require any polarization adjustment, always operating the output stage at pure Class-A to ensure a detailed sound scenario.


At the same time, the Active Servo Bias allows the use of different tubes such as KT88, KT90, KT120, KT150, 6550, without the need of any adjustment.





The U-280 SC 30th Anniversary LTD avoids the use of negative feedback, a common practice that results in a loss of details and sound richness.


To improve the damping factor without recurring to negative feedback, Margules Audio has developed the Back Electromotive Force Sensor system or BEFS, which changes the output impedance of the amplifier per the load requirement



The U-280 SC 30th Anniversary LTD is a low power consumption pure Class-A tube amplifier.


The Active Servo Bias and the BEFS (Back Electromotive Force Sensor) by continuously adjusting the polarization based on the signal rather than the tube characteristics, extend the tubes life expectancy, optimizing power consumption, reducing distortion, preventing overheating, and improving the damping control, resulting on the output stage to always operate in a full Class-A.



The output stage valves can be configured through the simple operation of a switch (triodes/pentodes), changing the transfer function, optimizing efficiency and tonal characteristics.





This amplifier can work without additional pre-amplification thanks to its input attenuators.





The U-280 SC 30th Anniversary LTD can be configured as a monoblock. This allows it to be used in conjunction with another U-280 SC 30th Anniversary LTD as double MONO increasing the power.



The U-280 SC 30th Anniversary LTD power/distortion curve is uniquely low in a non-feedback and tube circuit, thanks to its redesigned Active Servo Bias.





The low-level signal circuit is biased by a Shunt power supply that has no correction circuit. By not having a control loop circuit, avoids the induction of non-desirable harmonics, guaranteeing the integrity of the audio signal.




The ANA® technology (Neuro-Acoustic Alignment) is one of Margules’ technological innovations developed from a fundamental principle: the human brain perceives sound by prioritizing the harmonic structure above fundamental tone; that is, it focuses on how humans perceive sound and not on how we measure it.


This technological advance originates from the seductive sound theory (engaging sound) and is based on the way in which our brain decodes the information from the sound waves through the ears: when sounds are closer, they keep us focused due to the relation between perception and sound, the distance at which we perceive them and their intelligibility, whereas distant sounds, even when intelligible, do not catch our attention and are easily ignored.


Our ANA® technology is designed to achieve a realistic sound, with a wide frequency response, low distortion, and accurate harmonic reproduction, optimizing to the utmost the relationship between the source and the receiver, so that you can enjoy your music in a way you have never experienced before.



Margules Audio

Our Story More than 90 years of history implementing out technology with special attention to the innovation and design. Today the fourth generation of engineers and craftsman are devoted to challenge the boundaries of audio reproduction. Each piece of our catalog is handcrafted to implement our innovation with chosen components to achieve our specific design philosophy, ANA® ( Acoustic Neurologic Alignment ), focused in how we as humans process and perceive sound, prioritizing the harmonic structure over the fundamental tone. Our efforts, knowledge and talent are focused in the design and manufacture of High-Performance audio equipment with our own technologic proposal to bring unsurpassed audio experience. Thanks to our innovative technology and the sound reproduction quality, Margules® is today a World reference in the high-end industry. MARGULES ® is also interested in creating sound oasis, making integral sound projects that generate captive and enriching audio experience in different spaces. 1925 In the Early twentieth of 20th century A Rumor is heard by a young European engineer, Mexican President, Plutarco Elias Calles is inviting capable man to participate in the National Electrification Plan. Jacob Margules sees this as an opportunity and an ideal pretext to construct a new life on America. Jacob asks for a loan to his father-in-law and crosses the Atlantic along with his wife, his dreams and capabilities. 1927 His talent as an engineer is rapidly recognized in Mexican land and plays an important roll in the first national radio stations. In this country our name has been link to the sound reproduction since its origins. Rapidly acquires the needed expertise to step up and found a store called Emporio Electronico, focused on selling and supporting the new radio industry. In a short time is the gathering oasis of the aficionados and professionals of the radio enthusiast, later turns in to Casa Margules. 1954 As a result of the success obtained in Casa Margules the business grows in to two, the distributing company, Radio Surtidora, and the manufacturing branch, Tel Rad, where we can find the born of our legacy, is here where we started manufacturing reproduction instruments, gramophones, turntables, amplifiers and speakers. When High Fidelity begins to be possible, the Brand Marvox was created, under that brand where produced several Amplifiers, Speakers etc. Tel Rad and Marvox project was headed by Alejandro Margules, second generation on the company. 1981 The accumulated experience and knowledge  thru does day and the new generation brings new ideas: Julian Margules, grandson of Jacob Margules and son of Alexander Margules, has the vision to use this baggage to implement his own ideas, the Magenta line is born, first as an high performance biamplified active system . 1990 After years of RD, Julian Manage to bring together his Ideas and experience in a project that became an Icon: The U-280 , the first servo controlled full class A amplifier with no need for any type of adjustments an unprecedented thermal efficiency. The U280 has been awarded throw the decades by the specialized critics and press, The U280 always has been in continuous evolution. Due unique characteristics  is a worldwide reference in the High End  Audio. Today, Margules, continuous working with the same passion in new technologies to reproduce the music with a natural and reach sound and exclusive aesthetics. Our Mission is clear: give the deserved place to your music and space where you listen, so you can enjoy it at its best. 2004 Margules makes the first high End iPod interphase, the “I-end” with one of the first electrostatic tactile panels in the market, video feedback, fully remote control throw RS232 o IR, and converted any I-pod in a music server with a high quality audio characteristics. In 2006 Sterephile reports over it and 2007 In the CES at Vegas is consider by NBC  news as a high light at the show. It was develop around our Analog to Digital Enhancer ADE, that has been mention by StereoPhile as a killer product and received awards by many other publications. 2018 Thanks to the growing demand on our product, and a continuous quality improvement requirement, the factory was relocated at a bigger and very well-organized facility.