Line level Preamplifier CA-04

While following the basis circuit of CA-03, CA-03L of the popularity the details were upgraded furthermore.

CA-04 receives several prizes and be CA-03, CA-03L, of the popularity the vacuum tube ceremony pre amplifier of the highly efficient line level exclusive use that causes the line amplifier department to, the basis become independent and improved the details furthermore. Drawing vacuum tube of charm that is not to succeed the circuit and sound of an old type and hid and had that the many sounds of the quantity of information that passes in the present is drawn was designed to the purpose.

Adoption of the single no feedback amplifier of 6AK5W in the line amplifier department

6AK5W made of Telefunken that is having an extremely excellent tone quality to, the line amplifier department of CA-04 is being used with the single no feedback. It pours a somewhat much current into 6AK5W of small and make the load resistor as much as possible and be lowering the output impedance. It is as the moderate gain of about 16dB in our company because we become difficult to use it even if the amplification rate of the flat amplifier department is so too high. Also we avoid the influence by the bypass capacitor, without using the bypass capacitor for the cathode department of this vacuum tube and the extremely wide frequency characteristic that calls it with 0.5dB within to 10 Hz-150kHz has been materialized-.

We adopt the good DALE company production of the 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 CA-04 are adopting the U.S. DALE company production to most of the parts. There are many parts that the resistor made of the DALE company was made in conformity with the MIL spec. of U.S. and the tone quality excellent as it is not able to compare it with the thing of the same class of the domestic production. Also even several the steps of reliability is high more for the general.

Also we are mainly adopting the polypropylene capacitor made in U.S. to the capacitor. The responsiveness to the signal of the palace nature this polypropylene capacitor excels in comparison with, a usual chemical capacitor and also even the distortion rate of capacitor oneself excellent more very more 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, filling up it into the case made of the ebony into the capacitor of the part that influences the tone quality largely with high strength epoxy resin in the own company the tone quality has been improved.

For instance, we adopt sub Shashih made of the brass where prevents the influence of the vibration it is to the vibration control diligently.

The vacuum tube receives the influence of the vibration not a little constructionally. The influence to the sound of the vibration remains none the less, although 6AK5W that our company is adopting is the vacuum tube that adopted the vibration control structure. CA-04 prevents the vibration by establish firm sub Shashih made of the brass under the foundation and joining the foundation and sub Shashih in the checkpoint and be causing to useful for the tone quality improvement. Also the Shashih structure is firm by the frame structure by the side panel and stainless steel metal fittings by the undirt material of a firm cherry tree material and be as strong Shashih structure to the vibration.

Realization of beautiful form with the adoption of the front panel and side wood of a beautiful cherry tree material

We adopt the wood panel by the cherry tree undirt material of the domestic production to CA-04, of the front panel and side panel. Beautiful form was materialized to other department material with the adoption of beautiful aluminum Shashih of the thick 2 mm. This design is common with A-08, A-09 power amplifier of our company and both are considered to match the design target even the tone quality face as the pair.

The chromium copper production, our company original pin Jacques, we adopt the high trust type made of the Teflon to the socket to input-output pin Jacques.

The input terminal of this machine is adopting our company original highest-class pin Jacques who is to the outside conductor the shaving of chromium copper 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. This pin Jacques is connected from the ground side when he connects and be an advantage also in the cheap entire surface because he is becoming the structure that parts from a hot side when he draws out it.

It is evaluated highly also in the foreign country not only Japan inside to the vacuum tube socket and be adopting the unresonance type Teflon socket made by the own company. There is not a meaning no matter how the amplifier body is strengthened in the case that the feeling Go condition of the socket is loose. Because the amplifier of our company is the structure that prevents the vibration from the socket part the effect appears in the sound largely.

Adoption of the hospital grade gold plating terminal to the plug of the high quality line material to the power cable

The power cable of this machine adopts the high quality cable of with the inlet terminal of 3p and be using an original gold plating pin for the hospital grade plug of Panasonic to the plug department. 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.

CA-04 specifications.

Form: Vacuum tube line level exclusive use pre amplifier

Use vacuum tube: 6AK5W made of Telefunken 2 pcs

Biggest output: 8V

Frequency characteristic: 10-150kHz (-0.5db)

Remaining noise: 0.07mV

Line amplifier department gain: 16dB (about 6 times)

Input impedance: 50k ohms

Output impedance: 1.6k ohms

External form measure: 420 (W) 290 (D) 94 (H)

Weight: 6.3 kg


その他 : 弊社の加工技術を駆使した木材、樹脂等の精密加工も承っています。(詳細はお問い合わせください)
Besides: the processing technology of our company even the precise processing of the lumber, resin etc. that utilized it are informed. (Inquire the details)

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