To use the advantages of Class A without having to deal with its disadvantages – this is the goal of the German high-end hifi forge Octave Audio once again with the new Octave V 70 Class A, which is being presented these days as a new stereo integrated amplifier. A new amplifier concept is to guarantee an outstanding sound image.
Class A is a circuit concept for amplifiers in general, which is sufficiently recognized as particularly “musical”. This is also the view of the German high-end hi-fi manufacturer Octave Audio, and the company therefore strives to use this concept to its best advantage in its latest stereo integrated amplifier, the new Octave V 70 Class A.
Octave Audio describes Class A as a circuit concept that allows a particularly pure mid-range reproduction in amplifiers. The reason given for this is that a higher quiescent current setting ensures very low distortion in the form of second-order harmonics. This results in a virtually beguiling mid-range reproduction which, according to the unanimous tenor of all advocates of this circuit concept, promises a very warm, appealing sound. One thing, however, is not available here that would be equally desirable, and that is performance, according to Octave Audio. These deliver, for example, push-pull concepts many times over, but also exhibit higher inharmonic distortion.
In order to be able to use the advantages of Class A to the full, but still provide sufficient power, the new Octave V 70 Class A has been developed, based on a new amplifier concept, Octave Audio promises.
Andreas Hofmann, founder and chief developer of Octave Audio, was tempted to combine the two aforementioned amplifier concepts into something new, which, according to him, he has now succeeded in doing through extensive development.
Octave Audio describes the underlying concept of the new Octave V 70 Class A as a Class A push-pull amplifier in pentodes, which in turn relies on a newly developed Class A technology.
At the core of this concept is a way found by Andreas Hofmann to dynamically shift the limited dynamic range and thus the limited performance of the Class A concept upwards in accordance with the performance requirements. The German company refers to this as Dynamic Bias Control and thus describes a dynamic operating point adjustment which, in the form of a self-regulating Class A amplifier, enables almost double the output power. In this way, the new Octave V 70 Class A achieves 50 watts or 70 watts peak power in combination with the Octave Super Black Box. This means that the power potential of the new Octave V 70 Class A is clearly higher than that of conventional Class A amplifier systems and thus offers sufficient reserves to be used with a wide range of loudspeaker systems.
The manufacturer also expressly points out that this new principle guarantees the advantages of Class A over the entire frequency response, right up to maximum output level.
The new Octave V 70 Class A is equipped with four KT120 as end tubes and ECC 83 and ECC 81 as driver tubes, although the manufacturer expressly points out once again that there are a wide range of options available for realizing individual ideas. For example, an audio bias circuit is available for this purpose, in which the amplifier automatically adjusts itself to the tube being used, and therefore does not require an adjustment controller. Nevertheless, the proven bias measurement with coloured LED traffic lights is still available, even though this is only used to check the proper function of the four end tubes. In addition, the new Octave V 70 Class A, like other top models from Octave Audio, features a power preselection. Power High and Power Low are available here to optimally adapt the unit to the different end tubes. Power High is preset for the KT120, and can also be used for the KT150. According to Octave Audio, however, lower power tubes should be operated in Power Low, such as the KT88 or 6550, are mentioned here as examples. This means that the new Octave V 70 Class A would still have between 15 and 25 watts of music power available.
At the inputs, the new Octave V 70 Class A offers five Line In in unbalanced form, one balanced input, and optionally a phono preamplifier can be offered as an extension, designed for either MM or MC cartridges. Of course, a so-called bypass is also available to integrate the amplifier into home cinema solutions, for example. It also has a controlled pre-out for subwoofers, for example, and a record out is also included.
Of course, the new Octave V 70 Class A has not neglected to implement the typical Octave Audio features, such as a power management with electronic monitoring, which, based on a special power supply technology, protects the amplifier against various kinds of mains disturbances and reacts to increasingly noticeable mains fluctuations and higher-frequency mains disturbances in order to avoid any sonic dips. Even in this class, an ECO Mode is a must nowadays.
The new Octave V 70 Class A is available in either elegant black or brilliant silver, with the housing made of solid aluminium.
With dimensions of 451 x 175 x 405 mm, the new Octave V 70 Class A weighs in at 23 kg.
According to Octave Audio, the new Octave V 70 Class A doesn’t really require patience, but this new stereo integrated amplifier is now available in specialist shops. The recommended retail price is stated at € 8.500,-.
Getting to the point
After last year’s convincing performance with the newly developed single ended triode power amplifier Octave Junilee 300 B with Class A, another exclusive amplifier in pure Class A is now to be presented, namely the new Octave V 70 Class A. With the new Octave V 70 Class A, a new solution has been created that once again brings out the undisputed sonic advantages of Class A in a way that is suitable for everyday use, according to the promise of the German high-end hi-fi manufacturer Octave Audio. An enchanting musical performance is combined with power and therefore exciting dynamics.