Connects with CD player, and the highest sound quality is realized!
With input volume "2A3"Single stereo amplifier A-011
- The sound quality highest by CD player to direct connection! First power amplifier with input volume in our company.
Although our company came to be globally estimated by A-08 of a previous work, and A-08S 45 single amplifier, there were many people who wish the sound more than equivalent with a bigger output, and they were furthering development of new amplifier. Since 2A3 was comparatively apt to use sound quality as an output pipe well, it decided to adopt this. Although 2A3 has used A-08S of the previous work, although it demonstrated the capability which 2A3 has for operation by the same busy condition as 45 100%, it did not become precocious. By A-011, in order to demonstrate the capability which 2A3 has 100%, I examined the circuit to details. Moreover, I made it obtain the highest quality, as CD player connects directly by preparing volume in an input. Usually, since CD player has the high output level, there is output level sufficient also by not letting a preamplifier pass, either. Therefore, many some people use only an attenuator without a preamplifier. The simplest system is established by developing it further in this machine and making by the input dual type volume. We made it become possible to constitute a quality system. In the attenuator unit of every exception, a needed connecting cable is also omissible, and since wiring can also be performed by the shortest distance, a quality rise at these points cannot be overlooked, either. It is the optimal amplifier for the person of an idea as liking to reproduce an own reproduction system by the quality highest with the minimum composition. A-011 the driver stage and the output stage 1 since it consists of only this vacuum tube, if CD player is connected, the sound of CD will be played only through only two vacuum tubes. This can be called system of ultimate simple composition. A-011 will prove the sound quality merit of simple is the best.
- "80" was adopted, and the improvement in sound quality was achieved famous for sound being good for a rectifier tube in 717A as a driver tube.
A-011 used 717A with high evaluation as a driver tubes, and adopted 80 as the rectifier tube. Since it designed on the assumption that CD player was linked directly and used, this machine needs to make the amplification rate of amplifier larger than the usual power amplifier. 717A is the optimal vacuum tube, in order to obtain a big amplification rate, since Gm is high. This machine is designed so that the maximum output 4W may be obtained with the input voltage of about 0.4v. Thereby, if not only CD player but the gain is somewhat larger, analog equalizer amplifier and other input equipment are also connectable. It is also possible to control and use the level of an input, of course using the usual preamplifier.
- Adoption and an energetic sound have been obtained for the mass Schottky barrier diode of super-low impedance in DC ignition circuit of the vacuum tube.
The heating circuit of 717A and a 2A3 vacuum tube was considered as DC ignition of both waves rectification in order to hold down a noise to the minimum, and the large scale Schottky diode was adopted as the rectifier by the super-low loss of the U.S. International rectifier company. In A-011, the force on account of the low impedance is charm.
- Sound which adopted a troydal power transformer and a high-B type cut core output transformer excellent in the regulation, and was excellent was realized.
The merit in the sound quality side adopted the large troydal type as the power transformer of this machine by audition. Moreover, the cut core transformer excellent in the regulation high-B type is adopted as an output transformer and a choke coil. The core material of made-to-order 100-micron thickness was adopted especially as the output transformer like A-08S, the coil was rolled using the insulating paper of Teflon, and sound quality was raised.
- The high-quality sound part and custom-made part which were collected from all over the world were adopted as the key point, and the highest sound quality was aimed at.
The capacitor and the resistor currently used for that of this machine have selected carefully and adopted the part of the highest sound quality selected out of every country in the world by the audition. Especially the capacitor is using it for it by the epoxy resin further, carrying out fill it up of the polypropylene type which was excellent in sound quality to an ebony case. Since an electrode vibrated easily, the film capacitor achieved the big improvement in sound quality according to this fill it up effect. The capacitor of most including the power supply currently used for A-011 is reducing use of the chemical capacitor which is inferior in sound quality as these film capacitors made from special as much as possible. Moreover, the resistor is also carrying out careful selection use of the high-quality sound parts, such as winding resistance of DALE, and metalclad resistance and mass surface mount resistance.
Form : 2A3 single stereo power amplifier / Use vacuum tube : Two 2A3s (it not being attached and there being also - or an RCA 2A3 attached type), 717A 2pcs, 80 1pc / Maximum output : 4W+4W / Frequency characteristic : 20-30kHz(at time of 1W output)/Input sensitivity : It is 4W output at the time of 0.4V input. / Gain : 24.5dB / Residual noise : about 1mV / Input volume : 100k ohms dual A type volume / Input impedance : 100k ohms / Outside dimension : 400 (W) -- 294 (D) -- 204 (H) / Weight: 14.3kg