High Power  E505 Gold Seal Tube Pure Rear Stage Power Amplifier Board Class A


Introduction:
1. Use the original Ansemy MJ15024G/MJ15025G and Toshiba 2SA1930/2SC5171.
2. The interstage coupling capacitor adopts WIMA capacitor 1UF, with natural sound and wide sound field
The resistance adopts a five ring metal resistor, and the main circuit adopts a five ring metal film resistor with an accuracy of ± 1%, ensuring a good signal-to-noise ratio of the entire machine.
3. The PCB is made of 1.6mm thick double-sided sheet metal, with a thickness of 2.0A copper, and a gold plating process to ensure good current flow performance and PCB quality.
4. The feature of this board is the use of the currently advanced C1237 BTL horn protection circuit, which effectively eliminates the impact sound of turning on and off, as well as the DC output protection function, making your horn safer.
5. The wiring layout of the entire circuit board is quite rigorous and reasonable, and the overall PCB wiring adopts a single point grounding method. This power amplifier board works stably and reliably, with high output power; The voice is beautiful and round, with an open field. Strong three-dimensional sense, stable and solid low-frequency, excellent signal-to-noise ratio, and wide dynamic range; Clear details, excellent transient response, and able to handle various types of music, performing well in home playback environments.
6. The price is for a pair of boards

Parameter:
1. Power parameters: One set: DC+- (35V-55V) Recommended+-45V (AC: Transformer 300W dual 32V, rectification board required)
Another group: single AC12V (note: each board is independently powered by a single AC12V power supply, that is, one board is powered by a single AC12V power supply)
2. Power: 300 watts (total harmonic distortion THD+N<0.1%), DC+-45V, 4 ohms
3. Measured under Class A 80W, 4 ohm load
4. Horn impedance: 4-8 ohms.
5. PCB size: 87 * 334MM.
    Plate: 110 wide (including aluminum) * 334MM
6. First, adjust the differential input stage current to 2MA: adjust the VR1 (500R) adjustable resistor to make the voltage at C and D points 1.5-2V (i.e. the voltage at both ends of the R9 (1K) resistor); At this point, the input differential current is 1.5-2MA, which is a value of sound quality
7. The static current of the large tube is 100MA: Adjust the adjustable resistor VR2 (1K) to make the voltage between A and B points 22MV. At this time, the static current I=22MV/0.22R, which is 100MA; If the customer's heat sink is large enough, it can increase the static current, usually with a sound effect of 100MA-300MA.
8. Weight: 0.6KG+0.6KG

Package
1pair The New E505 Power Amplifier Board