Ｔｈe power amplifier that established "45" of the sound
"45"Single stereo amplifier A-08S
●We improved A-08 that received high evaluation furthermore 45' the final edition of the amplifier.
A-08 that is the antecedent of this A-08S was evaluated very highly among the mania of the single amplifier of the vacuum tube, for instance, receive high evaluation since the launching and receive the SOTA prize in Internet audio magazine 6moons of U.S.A There are many one that are combined with the high efficiency speaker such as the ALTEC and LAWTHER into one of the user, although it was becoming the bestseller of No.1 among the product of our company and be desiring and be making lower the remaining noise and was receiving the request a lot. The quality of the sound at the time of the small signal is important' in a high efficiency speaker it is thought that it was the vacuum tube that 45' of the tone quality were suited to those request most. There is the characteristic that the high efficiency speaker appears largely as it is even the noise not only the music signal. Therefore the noise level needs to be held down over a general amplifier.
A-08 was adopting the no feedback amplifier constitution with the single amplifier of the triode tube. Therefore there is a limit to restrain the noise level low in the case that we ignited the output tube AC. We did to that adopts the DC ignition with driver tube 717A, output tube 45 and launch as A-08S newly to solve it in our company. Finally the noise level is succeeding in restraining it in a sufficient low level for the single no feedback method. The level is becoming the level without a problem at all with the combination with a high efficiency speaker in the range of about 0.3mV～0.7mV.
The quality, although the output is small rather A-08S surpasses in all of have the tone quality that is not inferior in the 300B amplifier of the highest-class. As combine this amplifier with a high efficiency style speaker in our company and be obtained the highest tone quality it is designing it. We promote that adopts a high efficiency speaker by all means, to make the most of the performance tone quality that this machine has. We are answering it to the question regarding the matching speaker in our company. Please inquire it to our company for details.
We chenge the rectifier tube 5U4G to 80. Tone quality improvement was accomplished.
It was changed to 80 in A-08S, although we adopted 5U4G to the rectifier tube in A-08. ' The capacity and resisting pressure are very clear, although they are fairly smaller in comparison with 5U4G even more older vacuum tube 80 and be the clear sound the excellent rectifier tube that is obtained. Even the affinity is perfectly due to the vacuum tube that was made as the pair when 45 was developed as for the phonograph originally. Bloon style "45" old vacuum tube exists besides usual ST style with 80'. Those have original gentle good atmosphere even the sound, besides the form is interesting merely. Even these tubes can use it without special adjustment in A-08S. Please experience a precious vintage sound by all means.
Adopting the large capacity shottkey barrier diode of ultra low impedance in the DC ignition circuit of the vacuum tube we have obtained an energetic sound.
We adopted the large capacity shottkey diode of an U.S. international Rectifier company to the rectifiers of the heater circuits of 717A, 45 vacuum tubes. This diode is having a very low impedance characteristic with the thing that our company decided by the test listenning out of many diode in the world and the rectification loss is restrained low to about 0.3V and limit. The paucity of the insertion loss becomes sound and turn up. The force that does not show the smallness of the output in A-08S is a characteristic.
Being distorted the cut core transformers of the excellent High B type of all the performance to the transformer and the like with the concomitant use with the adoption, Teflon insulation paper the few excellent sound of the impression was materialized.
We are adopting the cut core transformer of excellent High B type to the regulation to all the power supply transformers, output transformers, chalk coils of this machine. The cut core transformer is that the performance and tone quality are good and there is an established opinion, it was adopted only to a high-class machine type formerly because the price is expensive. We omit the part that we were enclosing with the case conventionally to lower the cost of this transformer in our company and be nude and adopt and the cost of reduces the cover that covers all the transformer department without lowering the quality by adopting and adopted it the same transformer as the upper grade machine type particularly. Each transformer resins the resin to maintain the performance and be working at the maintenance of the quality. Especially we adopt 100 micron thick core material of the special orders similar to A-08 to the output transformer and wind by using the insulation paper of the Teflon and improve the roll wire method newly as for A-08S and be improving the frequency characteristic.
We adopt the DALE company production of the good sound to the resistor and the like and the capacitor to a main part to the adoption of the few polypropylene film capacitor of the distortion
The resistor and the like that are using it for A-08S are adopting the U.S. DALE company production to most of the parts. To a large resistor the etal crad style of the noninduction type, the wire wound resistor, we are using appropriately the metal film resistor to the type of the small capacity to the middle capacity type. With the whichever same DALE company production the tone quality is excellent as it is not able to compare it with the thing of the same class of the domestic production. Also it is high greatly because it is manufactured in conformity with the MIL spec. of U.S. even the reliability.
Also we are mainly adopting the polypropylene capacitor to the capacitor. The responsiveness to the signal of the palace nature of the ratio sob this polypropylene capacitor excels in a usual chemical capacitor and also even the distortion rate of capacitor oneself excellent very much. To influence largely also in the power supply circuit not only the signal circuit the capacitors of many parts including the power supply circuits the difference of the tone quality in this capacitor adopts the polypropylene type we are measuring the tone quality improvement through the means. Furthermore, we are adopting an our company original capacitor, to the cupring capacitor of the input capacitor and signal system of the big power supply of the influence to the tone quality most. These are the one that resined the film capacitor by the epoxy resin into the case of the ebony or bakelite and have accomplished a big tone quality improvement by preventing the vibration of the element.
So that equip the ammeter of the output tube and be constantly able to check the condition of 45 precious vacuum tubes it became.
The vacuum tube of the vintage is a precious thing. Just the condition of the output tube saw it with the eye we do not understand the merit and demerit well. If it is able to monitor the current of the output tube we are almost able to grasp the condition of the vacuum tube. The current of the output tube we arranged the ammeter that is possible to A-08S direct reding. Changing the vacuum tube of the right and left with the switch on the right side of the meter those current value can be read. Thus the exchange time of the vacuum tube can attach the guess approximately and became convenience very much.
To the vacuum tube socket our company original Teflon production, pin Jacques made of the chromium copperinput terminal, we adopted the speaker terminal made of the pure copper to the speaker terminal.
Established opinion of be of be adopting the socket made of the Teflon, highest-class pin Jacques who is to the outside conductor to the adoption, input terminal the shaving of chromium copper with the height of the reliability in the socket of this machine and send the terminal, to the inside pin the neighbour bronze shaving and adopt the that circle pin terminal and adopted the Teflon as the insulation material. Sending the pure copper shaving to the output terminal we are adopting the large terminal of the Teflon insulation with the gold plating. Even the speaker cable of the thick yarn called thickness 8 ? is enabling the connection to this. It is the highest-class part that even the simple substance sells individually and be evaluated whichever highly, although these are our company original parts.
Adoption of the beautiful very hard African ebony circle stick of the sound to the leg
Starting to shave the African ebony material with the established opinion to the leg of this machine with the beautiful case of the sound we are adopting it. The sound is beautiful with the material that this African ebony material is used to the oboe and the clarinet actually, be receiving high evaluation even for the material of the setting base of our company. The leg is fixed in Shashih made of direct complite to obtain the goodness of the strength and sound and be supporting it the whole weight accurately.
Adoption of the hospital grade gold plating terminal to the plug of the high quality wire material to the power cable
The power cable of this machine adopts the high quality cable of with the inlet terminal of 3p.
Even that we exchange to the cord of the hope of the customer is possible because we are adopting 3p inlet Jacques to this side of the body. When the quality will improve even the vacuum tube amplifier the change of the tone quality by the power cable comes come to turn up sensitively. Even the change of the sound by the power cable please have fun by all means.
Spec.
Form: 45 single stereo power amplifiers
Use vacuum tube: "45" (the vintage articles made in U.S.) 2 pcs, 717A 2 pcs, "80" 1 pc all standard belonging
Biggest output: 2W+2W
Frequency characteristic: 18-30kHz (1W output at the time of)
Input impedance: 200k ohms
External form measure: 400 (W) 294 (D) 204 (H)
Weight: 14.3 kg