The circuit refers to the 3850 preamplifier. The circuit is a preamplifier worthy of making and admiring. If you do it with your heart, the effect is much better than the general preamplifier, more relaxed, more delicate, warmer and charming, because the classic is far from the ordinary tube. Compared with the preamplifier of the op amp, the sound can be compared with the timbre of a tube
The circuit architecture uses the operational amplifier as the basic amplifier. Discrete parts are added to increase the open-loop gain, and the voltage and current dual feedback circuit is used to reduce distortion. The output tube uses the British original famous tube ZTX450 ZTX550, and the output is in Class A status. The music tastes very good. Bold
No need to debug the board
PCB size: 155X136MM
Transformer input voltage "AC14VX2 to AC18VX2 is all right, and 24V transformer can be used.
The resistors and capacitors of the components are all very high-profile materials to ensure that the circuit can perform 100% perfectly
The kit materials are very good. In addition to various original pairs of tubes. The capacitor adopts the British NOVER main filter, ELNA brown god WIMA decoupling 718 military resistance. Double-sided military PCB
The standard op amp is Philips NE5534, customers can upgrade other single op amps, such as OPA627, LME49710, OPA1611, etc.
Need to buy a chassis can contact us