Scottish audio manufacturer Linn has officially announced the global release of a mono power amplifier named the Klimax Solo 500. The designers claim that the Klimax Solo 500 is the finest compact mono power amplifier they have ever produced. This model features proprietary technology known as Adaptive Bias Control. Additionally, the method used to maintain the amplifier’s stability and coolness in all conditions is noteworthy.
Linn Klimax Solo 500: Class AB mono power amplifier
The Klimax Solo 500 from Scotland-based Linn is a completely new design, based on the basic principles of what they claim to be the most successful amplifier ever, the Klimax Solo. The designers say they have maximised the potential of every cubic millimetre in the solid-metal cabinet to create a product that is an improvement on its legendary predecessor in every conceivable way. And it’s still a relatively compact unit.
The Klimax Solo 500 combines the latest cutting-edge innovations in a single package. The synergistic combination of adaptive bias control, an advanced hybrid cooling system and a precision-crafted chassis results in a Class AB amplifier that is much greater than the sum of its parts, yet noticeably smaller than its peers.
The engineers have skillfully miniaturized the amplification and power supply technologies and placed them in the sleek and minimalistic housing. The compact size is particularly suitable for active setups and scenarios where space is at a premium.
Linn Klimax Solo 500: Adaptive Bias Control
Adaptive Bias Control is the groundbreaking, in-house developed technology first introduced in the 360 Exakt Integrated speakers, subsequently optimised for integration in the Klimax Solo 800 and now a crucial part of the impressive performance of the Klimax Solo 500. It ensures optimum output performance under all conditions and for the entire life of the product.
Conventional Class AB amplifiers require the application of bias current in their output stage to reduce transistor crossover distortion. This corrective bias current is manually set only once by the engineer building the product. Due to variations in manufacturing tolerances of individual transistors, temperature fluctuations during use, and the age of components, this estimated bias current begins to drift far from the ideal value (and continues to do so over the life of the amplifier), resulting in ever-increasing audible transistor distortion.
Linn says Adaptive Bias Control solves this problem. At any given moment during operation, the optimum bias current is set intelligently and in real time in the Klimax Solo 500. The current sent to each of the eight output transistors is continuously measured, sampled and digitised, and then passed on to a powerful FPGA processor, which calculates the required bias at that precise moment. The FPGA simultaneously implements a digital control loop to adjust and maintain the bias current at the measured optimum for the transistors.
The Klimax Solo 500 therefore continuously measures and corrects its own output to be optimal at all times; at any temperature, regardless of volume or sudden dynamic changes in the received music signal, and throughout its entire long service life. Crucially, the Klimax Solo 500 performs identically to its neighbours, ensuring a flawless and consistently balanced performance between all amplifications in the system, permanently.
Adaptive Bias Control is a key factor in the Klimax Solo 500’s extremely low noise floor. Thanks to this implementation, the Klimax Solo 500 measures 85 times less total harmonic distortion and noise than its predecessor under normal listening conditions.
Linn Klimax Solo 500: hybrid cooling matrix
The Klimax Solo 500 features a brand new thermal management system, i.e. a hybrid cooling matrix. This allows the amplifier to adapt to the demands placed on it and remain cool and whisper-quiet at all times.
The hybrid cooling matrix works as follows. All internal electronics are mounted directly, upside down, to a sub-chassis. This sub-chassis consists of a highly conductive block of hard anodized aluminum, mounted to a thermal plate. This sub-chassis draws heat away from the underlying electronics and is isolated from the amplifier cabinet. The thermal plate features a series of machined fins. Designed and optimized using advanced simulation software, these fins form a labyrinthine network of precisely measured channels on top of the thermal plate. At this stage and under these conditions, the fins naturally radiate heat upwards and outwards through precision cut fins in the amplifier’s top cabinet. This natural convection and radiation system is ideal for keeping the Solo 500 cool during everyday listening sessions.
However, when the amplifier is put under heavier load, the Klimax Solo 500’s hybrid cooling matrix really gets smart. In order to safely keep the amplifier cool for optimum performance, efficiency and preservation of electrical components, the Solo 500 must now switch to active cooling using two internal fans placed deep within the product. The fans force cool air through the network of channels on top of the thermal plate, which is the hottest part of the product.
The intelligent fan management system implemented by Linn in the Solo 500, controlled in real time by an FPGA processor, allows the required fan speed to be determined based on a combination of both the measured internal temperature of the amplifier and the input signal. This ensures that the fans run silently at the lowest possible speed at all times, while providing sufficient cooling to prevent overheating and thus maintain optimum performance, listening experience and efficiency.
The effectiveness of the hybrid cooling matrix is supported by a specially optimized Utopik power supply. Automatic voltage rails ensure that the output of the Utopik also adapts to the audio signal itself and only delivers the necessary power, depending on the playback and the volume. Less excess energy is generated, which would otherwise be lost as heat. This improves efficiency, minimizes the internal base temperature and the Solo 500 consumes less power overall.
Linn gives a power rating of 250 watts into eight ohms and 500 watts into four ohms. The output impedance is 0.01 ohms at 1 kHz. This gives a damping factor of 800 at eight ohms.
Linn Klimax Solo 500: Build quality and design
The overall appearance of the Solo 500 is one of minimalist and refined beauty. Upon closer inspection, the solid-material cabinet is characterized by finely designed and characteristic details. Thanks to the seamless construction consisting of only three precisely machined parts (base plate, housing and rear panel), the Klimax Solo 500 gives the impression of a single piece of aluminum.
The eye wants something too. The shape of the frontal view is new; a modern evolution of the signature Linn ‘smile’. Below the smile is a completely flat face, while the upper half is machined with a compound curve on two axes. In different lighting, this precision-machined detail produces a pleasing variety of reflections. A variable fillet in the aluminium evolves into a bevelled edge and a striking centrepiece; a backlit Linn emblem in the centre of a miniature roundel, with radially grooved chrome finish and a steel outer ring.
The ventilation openings on the top of the housing are equipped with fins with luminous surfaces. The cut-outs are subtle, concealed and invisible from the front. Three solid steel feet, impregnated with rubber O-rings, form an extremely stable and insulating platform for the amplifier and visually fit in perfectly with our contemporary products.
Soft animations of the LEDs behind the central mini-circle indicate the amplifier’s status. When the amplifier is in operation, the white light spreads out, creating a soft glow around the outside of this attractive and refined detail. The badge construction also has depth, dynamically reflecting light from different positions. Each amplifier in the room reflects light and creates its own shadows, contributing to the distinctive, striking aesthetic of the Klimax Solo 500.
