nlevo.gif (119 bytes) Integrated Tube Amplifier ASV TA-60 ndesno.gif (118 bytes)

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An Excellent Tube Audio Component

It is the fact that the design of audio components has been going back to the tradition, to what was once discarded as obsolete, of course in more developed in modernized forms. The question is why? Why should old and maybe obsolete designs be revitalized and redesigned? Why should long forgotten vacuum tubes be used again in high quality audio components?
It should be admitted too that interest for audio components with tubes has never really died. During the period of absolute reign of transistors, ICs, hybrids, and mass robotized production of audio components, a significant number of audio fans remained devoted to the old-fashioned and unique and perhaps exotic atmosphere created by the glow of tubes.
Several manufacturers have never discontinued this tradition and many
new ones are entering the market.
Acknowledgment for the revival of tubes is to be paid to some Japanese designers who earned international recognition and acclaim. They have designed unique tube amps noted for their simplicity and minimum number of components employed.
It should also be noted that the quality of all audio components has improved significantly. There is a great supply and choice of high quality and good value audio components.
There is no uniform answer to the question "Why" asked at the beginning. It shall have to be answered by each audiophile individually. We have spent years looking for an answer to this rather rhetorical question. And the answer is here in front of you. We shall be most pleased to share it with you.
The concept
The integrated tube amplifier ASV TA-60 is at your disposal. It is the result of years of careful and persistent development and design. There have been no compromises in achieving ultimate quality. The ASV TA-60 has been designed as a stereo 2x30W block fitted in the housing containing two power stages, a power supply and a passive preamplifier stage with inputs for CD, tuner and tape, and REC output, a quality input switch and an Alps stereo potentiometer. Thanking to a relatively high level of input sensitivity no separate preamplifier is needed, except for MM or MC phono cartridges.
The housing is made of quality nickel-plated or varnished steel sheet. Two output transformers in metal housings, circular array of tubes on top panel and functionally designed fron panel all together contribute to an overall elegant look of the tube amplifier. Rear panel is fitted with output and input signal terminals, fused AC inlet and power switch.
The circuit
All components built in the ASV TA-60 were carefully selected: polypropylene capacitors, metal film resistors, ceramic tube sockets, toroidal power transformer, quality electrolytics, high quality input and output terminals, Alps potentiometer, Mogami cables, etc. In the basic design the principles of Williamson topology were followed. As active components in the input and the driver phase-splitter stage dual triodes ECC 83 (12AX7) are used. In the power stage the EL 34 ( 6CA7) pentodes are employed in the cathode bias circuit. They work in the push-pull AB1 configuration with a high quality double C-core output transformer. Mode switch located on the top panel enables to alternate the operation of power valves between triode or ultra-linear mode. Both modes provide a clean and airy performance and deliver trully classic warm tube sound. An extra feature of this amp is an aptional application of a small amount of overall negative feedback (-5dB). The switch is on the rear pannel.
The output transformer
A high quality output transformer is the heart of a tube amplifier. A poor output transformer fitted in a well designed amplifier will spoil its performance.
Needless to say that the design and optimization of an output transformer takes high skill and know-how because performance requirements are complex and high. The transformer must deliver adequate and constant power without core saturation. It should provide wide frequency bandwidth at minimum distortion. Moreover, it should provide constant outstanding performance to retain the open, spacious qualities of recorded music. The sound quality of ASV output transformers is exceptional: low distortion and an extremely wide frequency and dynamic ranges.
The present AOT-30 transformers have a double C core and are carefully wound, have no internal solder joints and are impregnated and encapsulated in metal housing.
Performances
The final results are excellent and also confirmed by measurements. The TA-60 re-creates the glory of tube sound, it focuses well, has very good depth and transparency with fine image width.
The ASV TA-60 tube amplifier is manufactured in the classic manner of manual soldering of all components and joints. All elements and connections are entirely hard-wired on the circuit assembly. No printed circuits are used in this amplifier.
We believe that only such a manner of manufacture can, together with a great degree of skill, know-how and enthusiasm, provide the result: warm, natural sound without disturbing, sharp transients. An outstanding quality of reproduction from an amplifier like this can be enjoyed for hours and hours.

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