Product Description:
E405 is an upgraded version of E305. Compared with E305, it belongs to the diamond-diamond structure with double differential input of FET and has extremely low crossover distortion. Unlike E305, E405 is pure DC. The feedback capacitor is a current negative feedback type with excellent dynamic response and diving depth. Refer to the pure power stage of AccuphaseE405, with a DC servo circuit (played by OP07 with extremely low noise), Omron relay + C1237 speaker protection is Your speakers are escorted; increased output overload and overcurrent protection.
E405 sound characteristics: natural and slender, wide sound, excellent large dynamic effect, the biggest feature is the deep bass dive.
Product details:
1. Using original Toshiba A1943/C5200 and 2SA1930/2SC5171.
2. The inter-stage coupling capacitor adopts WIMA top-level capacitor 1UF, and the main circuit of the electrolytic capacitor signal adopts imported Panasonic brand, which ensures strong and continuous power support.
3. The five-ring metal resistor is used as the resistor, and the five-ring metal film resistor with an accuracy of ±1% is used in the main circuit, which ensures a good signal-to-noise ratio of the whole machine.
4. The PCB adopts 1.6mm thick double-sided sheet, 2.0 oz copper thickness, and full tin spraying process to ensure good passing performance of large and small currents. Top-notch PCB quality.
5. The biggest feature of this board is the use of the current advanced C1237 BTL speaker protection circuit, which effectively eliminates the impact sound of opening and closing and the DC output protection function, making your speaker safer.
6. The wiring layout of the entire circuit board is quite rigorous and reasonable, and the overall PCB wiring adopts a one-point grounding method. The power amplifier board works stably and reliably, with large output power; the sound is beautiful and round, and the sound field is wide. Strong three-dimensional sense, stable and powerful low frequency, excellent signal-to-noise ratio, wide dynamic range; clear details, excellent transient response, easy to play all kinds of music, and has a very good performance in the home playback environment.
Basic parameters:
1. Power parameters:
One group: DC+-(35V-55V) recommended +-45V (AC: transformer 300W dual 32V, need to add rectifier board)
The other group: single AC12V (note: each board is powered by a single AC12V power supply independently, that is, one board is powered by a single AC12V power supply)
2. Power: 300W (Total Harmonic Distortion THD+N<0.1%), DC+-45V, 4 ohms
3. Class A 90W, measured under 4 ohm load
4. Speaker impedance: 4-8 ohms.
5. PCB size: 59*236MM.
Board size: length 236* width 95* height 30MM
6. First adjust the differential input stage current to 2MA: adjust the VR1 (500R) adjustable resistance so that the voltage of C and D points is 1.5-2V (that is, the voltage across the R9 (1K) resistor); at this time, the input differential current is 1.5- 2MA, this value is the best sound quality
7. The quiescent current of the large tube is 100MA: adjust the adjustable resistor VR2 (1K) so that the voltage of A and B is 22MV, at this time, the quiescent current I=22MV/0.22R resistance is 100MA; if the customer’s heat sink is large enough, it can make Increase the static current, generally 100MA-300MA sound effect is the best.