Phasemation CA-1000 Preamplifier
I. Analog amplifier section consisting of two mono-block units
The amplifier units consist of the shaved 20mm thick aluminum front panel, 2mm thick copper plating steel chassis base and 3mm thick aluminum cover; so it has the strong chassis structure. The amplifier units separated into L/R and the separated powerful power supply unit support the playback sound by which you can enjoy music expressing the overwhelming liveliness and re-creation of vistaed stage because of the high resolution and high S/N ratio.
The volume adjustment circuit which is the core of this equipment has a necessary and sufficient volume resolution (46 steps) and the hybrid attenuator (patent technology) by which the input at high impedance and output at low impedance are achieved without using the active elements is adopted; in addition, the remote control function is realized by utilizing the high sensitivity relay as a volume adjustment element. Therefore, even if the volume is narrowed down, you can enjoy the music keeping the excellent penetration capability without degradation of sound quality.
II. Separated unit of the power supply section incorporating the control circuit
1. To avoid the effect of noise against the analog amplifier circuits, the control circuit mounting a CPU is assigned to the inside of the power supply unit; furthermore, the relay driving circuits in the amplifier units are controlled through the I2C (Inter-Integrated Circuit) communication. In order to prevent the digital noise from being mixed to the analog circuits, this control circuit and communication are not operated and the CPU enters in a sleep status when playing music.
2. The luxurious rectifier circuit consisting of the R-core power transformer having more capacity than necessary, 5U4G which is the rectifier tube not generating a switching noise principally and the two choke transformers separated to L/R is adopted. In addition, the high S/N ratio is achieved by adopting the DC power supply circuit for the vacuum tube heater using a 3-terminal regulator.
III. Adopting a variety of input- and output-switching functions
1. As the input terminals, three audio lines for RCA and XLR systems are respectively arranged. In the XLR input circuit, the balance/unbalance conversion transformer designed anew is installed; so even a minute signal can be played at high S/N ratio at high resolution.
2. As the output terminals, one audio line for RCA and XLR systems are respectively arranged. Similarly, the output transformer designed anew is installed; the output at low impedance (100 ohms or less) which we have aimed thoroughly is achieved.
3. To utilize the specialty of the hybrid attenuator (patent technology) by which the input at high impedance and the output at low impedance are achieved, the direct output terminal outputted from the attenuator without passing through the amplifier is arranged. Please enjoy the attenuator output of being proud of outstanding freshness; in addition, the remote control function can be used.
IV. Tube type non-feedback unit amplifiers
The output-buffer 6922 (6DJ8) and the non-feedback SRPP amplifier circuit ECC803 (12AX7) which excels in transient characteristics and has a reputation for sound quality are adopted. You can enjoy the charming vigorous sound quality having a wide dynamic range because of a vacuum tube non-feedback amplifier.
V. Solid chassis structure
To remove an unnecessary vibration, machined 20mm thick aluminum parts are adopted for respective front panels. The respective covers are a hybrid structure made of a 3mm thick aluminum panel and a 1mm thick copper plated steel plate. To enhance the rigidity, a 2mm thick copper plated steel plate is adopted for the chassis. In addition, unnecessary vibrations are removed by combining different materials and adding a wood base under the chassis.
Input and output terminals evaluated as high product quality and high sound quality made by WBT and NEUTRIK are adopted.
The completed product having the dignity and high universality will not disappoint you on the owner’s joy.