QC2350 Power Amplifier Home Theater Power Amplifier 350W/8 Ω 700W/4 Ω 220V XLR/RCA Output

Main parameters:

Output power: 350W @ 8 Ω @ THD distortion 1%

             700W @ 4 Ω

Recommended load impedance: 4 — 16 Ω

Total harmonic distortion:<0.01% @ 250W 20Hz — 20KHz

Frequency response: 5Hz — 50KHz

Signal-to-noise ratio:>110DB

Static power consumption:<3W @ standby state<400W @ static power consumption (no music output)

Input voltage: 220V

Overall size: 480mm wide, 280mm high (including foot nails), 500+45mm deep (handle)

Operating weight: 60KG

Power Supply:

Someone once described the power supply as a successful heart, which shows its status in the eyes of enthusiasts. The same is true. If there is no good power supply, the best line is zero. The QC2350 standard is equipped with a Tianxian wiring base and a feverish power cord with a red copper gold-plated plug tail. The power tail on the power amplifier body is also our customized red copper gold-plated product. The pure silver fuse is not loose at all. The DC power filter device can eliminate the cow hum caused by the dirty power supply (with DC component), and set the opening and closing (through) function. The burning friends can compare the opening and closing sounds, and you can use the setting which is suitable for you. In the through state, the current does not pass through the switch, but through a 30A silver contact relay, ensuring the purity of the power supply.

The whole machine adopts a 3000VA power transformer, with 1500VA independent power supply for each channel. It is made of Japanese Z11 silicon steel sheet, high purity 4N oxygen-free copper enamelled wire, with epoxy resin filled in the middle to reduce the vibration of the transformer. The input and large current output wiring of the transformer adopts imported Teflon oxygen-free copper silver-plated wire.

The power supply system of this machine is quite unique. The amplifier circuit of each channel of the machine has a total of three power supply circuits, which are independent windings and independent power supply circuits. The power supply circuit of the final high-current amplifier stage is composed of four TO220 encapsulated 60A current ultra-fast rectifier diodes per channel, and two screw-mounted high-current 100V33000uF imported from Europe and the United States for each channel (the main filter is upgraded to two Nikkeon 100V68000uF ultra-large reservoirs per channel). The big pond is not installed on the PCB board, but is installed independently. The connection line of all capacitors is also made of 3 square meters of imported Teflon oxygen-free copper silver-plated wire, which plays a significant role in the strong power of the whole machine, the bass effect of the explosion and the reduction of details. The voltage of the voltage amplifier stage is high and the current is small, so the rectifier circuit is composed of 8 ultra-fast recovery diodes with a current of 2A. The filter is composed of 14 high-quality capacitors of 330uF. With a stable and reliable series voltage stabilizing circuit, the output voltage is stabilized at+- 92V. Practice has proved that this is very effective for improving the sound details and stable and accurate sound field. The power supply of the input balance board is also a separate group of power supply, using the simple, reliable and effective American ON three-terminal voltage stabilizing IC.

Amplifier board part:

I think the power amplifier board should not be introduced too much, because there is nothing to talk about circuit analysis. After all, few of them learn this part. All amplifier tubes and constant-current source tubes of this circuit all use American ON transistors in one color, and they are quite famous tubes in the HIFI field. The input stage uses the diamond diamond circuit structure commonly used by the Japanese Golden Voice. The high frequency extension of this circuit is really good, and it is hard to listen. Specifically, the frequency response is wide, and the distortion is small. I really like this circuit, The signal amplifier tube and constant current source circuit of the input stage both use A92/A42 matching tubes. It is said that this type of tube is used less. ON Company has stopped production, and now can buy all the stocks in the past. When one is used up, one will be less. We have tried to use tubes of the same model of other brands, and the final conclusion is that it can not be replaced…..

The second stage amplifier and related auxiliary circuits use the ON company's MJE340/MJE350 matching tubes, which are more suitable for use in this place than the Hitachi 2SD667/2SB647, because the MJE340/350 has higher withstand voltage, higher current, and is also a low-noise tube, with a thicker sound. The current amplification stage uses MJE15032/15033 matching tubes. The driving capacity of this tube is strong. The driving capacity is four times that of the common Toshiba driving tube. The performance is stable. The sound will not become rough due to the increase of the current. The final current amplification stage uses MJE21193/MJE21194 matching tubes, which are known as the king of tubes. Eight pairs of tubes are output in parallel. The current output ability is first-class and the control force is excellent. A 330uF decoupling capacitor is arranged on the side of each power amplifier tube to make the work of these power tubes smoother and the power supply cleaner. All places with high current on the PCB board are welded with 1.6 square meters of single crystal copper silver-plated wire to improve the conductivity of the circuit.

The coupling capacitor adopts the UPP series audio capacitor of the highest level in Bennik, Taiwan. We ordered it directly from Bennik factory (because there are many fake products in the market, it is difficult to distinguish). The capacitor adopts pure silver pin, ultra-low loss angle, and good frequency response and accuracy. We have compared with many mainstream capacitors in the market, and finally chose the most comprehensive Bennik UPP capacitor, The sound of this kind of capacitor can be completely comparable to the priceless capacitor abroad.

The input signal line is a European brand single crystal copper silver-plated wire (not to mention the brand), the output line is AQ speaker wire (not to mention the ordinary surround wire), the input RCA is a domestic customized red copper gold-plated product, and the output speaker terminal is powerful, the authentic Taiwan MPS pure copper gold-plated (10u) terminal