Enthusiasm and powerful expression
Quest for gentle and beautiful sound of vacuum tube
DescriptionAccuracy of basic performance and reproducibility supported by high-definition device and powerful power supply.
Pull out the attractiveness of WE pentode
Western electric high-performance pentode WE 408A for the vacuum tube. A resistor was loaded on the output of the DA converter, and it was connected directly to the input part of the vacuum tube as it was, and made it as a single non-feedback amplifier of one stage configuration.The current to the screen grid which greatly affects the sound quality was supplied through a constant current circuit by MOS FET, and the purity of the sound was improved. The heater circuit is rectified in double-wave with a large Schottky diode and independently supplied right and left.Incorporated a design policy that reduces the number of using elements to the limit, it is configured to simplify the circuit so as to maximize the purity of the sound.
Mono configuration of PCM 1794A to DA converter IC
The output of the PCM 1794 A DA converter IC has a monaural configuration and has four output sections for operation output, though only one of these outputs is used, and the other terminals are not used by adding dummy resistors.It seems to be a wasteful way of use, but the purity of the sound is higher than that of the parallel connection.
Supplying from individual regulator circuit eliminates interference with circuit by power supply
Large capacity toroidal transformer for power transformer,Independent windings for analog and digital, then it issuppressing each other's interference.The transformer is an elaborate power supply circuit that separates the digital part, the analog part, and for the output circuit, make them independent, supplied from individual regulator. Teflon insulation and silver plated copper wires are adopted as wiring material with extremely high reliability and excellent sound quality.
|Digital input terminal||Coaxial 1 line (RCA)|
|Analog output terminal||Coaxial 1 line (RCA)|
|Vacuum tube||WE408A x2|
|Corresponding frequency||32~192kHz(Automatic tracking)|
|Sampling filter||8 times oversampling digital filter|
|Signal/Noise ratio||78dB (IHF-A )|
|Output impedance||2.6k ohms|
ReviewThe reason why the brand was made using the tube called WE 408A on this machine is not limited to simple bulbous seasoning,I think that this is due to the intention of actively reflecting this pentode.For example, it can be said that the transistor modelYDA-01 is more abundant in treble range of information amount and wideband.However, on the contrary, I think that the taste of the vacuum tube is sufficiently drawn out for the thickness of the low range and the stable energy balance.Particularly, thick sounds with power on low range may be due to WE tubes.Listening to jazz makes it easy to understand the difference.Although there is no diffrerence in bleed-free touch andthe depth of pitch of the Wood base, the body resonance of the torn sound was felt thicker than it sounds.The same can be said for the tone of the piano and the instantaneous power of the kick drum.It is a kind of clearly impression.In the orchestra too, the solid resonance of bass string lowered the center of gravity,The string instruments and wood tubes are rich in moisture and glossy solid finishing. Slightly contrasting with YDA-01 which felt delicate softness, YDA-01B is characterized by instantaneous crisp and strong clarity.When seeking some kind of enthusiasm and powerful expressive power in music,I think that the model YDA-01B will demonstrate its charm.Also note that it is never "old sound". The basic performance supported by high precision devices and strong power supplies guarantees the accuracy of reproducibility.