Description
Pre-biliary-PRT06A tube preamplifier (fever preamp)
Reference Matisse circuit (280V version)
We refer to the original Madis (high voltage 400V power supply, and tube, the first level is 12AX7, the second level is 12AT7)
According to the actual situation, we are divided into two and developed separately:
1, PRT06A (280V single tube version, economical type)
2, PRT06B (400V and management version, fan type)
PRT06A design thinking:
1. Compared with the original machine 400V power supply, 06A uses 280VDC DC power supply to facilitate the customer to use 400VDC withstand voltage filter capacitor.
2. The screen voltage is the same as the original machine.
3. The resistance is modified to be equal to half of the current and the current of the tube (that is, the current is the same as the actual single transistor current of the original machine)
4, DC filament power supply, to avoid the impact of voltage fluctuations on the filament
Listening introduction:
The test uses Twilight's 12AX7+12AT7 (also measured 12AX7), the most special in the low frequency, the depth of the dive, the strength, the bounce is unmatched by many stone preamps, when using the imported tube EN foot test, the details are more Rich, quieter and more mellow.
PCB size: 100*177*1.6MM FR4 Class A plate
Power supply requirements: 0-220VAC*40mA, 0-15VAC@1A
Note: This is a bare PCB and does not contain any equipment.
