2X60W pure class A mixed power amplifier with excellent sound

This is a gallstone hybrid power amplifier, the original design intent is not a simple combination of their own strengths. But the use of bile ducts can achieve the simplest level of voltage amplification and promotion. Minimize the signal flow. Try to keep the original flavor and reduce distortion and sound staining and additional distortion.
This feature cannot be achieved by using transistor single-stage amplification.

This circuit has the following characteristics;

1. Amplify and promote the primary bile duct voltage.
2. The voltage amplifying stage is connected in parallel with SRPP to make it work in Class A state. It has lower output impedance than single-stage SRPP amplification.
Higher magnification, and smaller distortion factor.
3. Multi-power supply design minimizes the impact of involvement between all levels.
4. The use of general genuine components can achieve very beautiful sound, which is beneficial to reduce costs.
5. There is only one-level capacitor coupling.
6 The work is very stable. If the power amplifier tube is selected strictly, the output DC drift can be two decimal places.

Figure 1 is the circuit diagram:

Production and debugging points:

First, the power amplifier level:
1 Try to make the parameters of the two connected gallbladders consistent to make them work in the single-stage SRPP state, and then measure the resistance of the two cathodes separately.
Choose a bile machine with the same voltage.
2 The total current of the voltage amplification stage should be at the right of 10MA. If there is a deviation, it can be achieved by adjusting the size of the cathode resistance and increasing or decreasing the power supply voltage. But cannot exceed + 260V.

Second, the current output stage:
1 Adjust W1 so that the total current of the three pairs of transistors is about 1.8A: adjust W2 to make the DC potential at the output end zero.
2 The envelope volume of the radiator of each channel should not be less than 45X16X4.5 CM.
3 All the stone particles must be fixed on an integral heat spreader, and then tightly coupled with the radiator by silicone grease. Each stone particle must be fixed with silicone grease.

Three, power level:
1 This machine uses a 500W E-type cow, and there are two reasons for not using the ring cow. One is that the E-type iron core is warmer and richer from the sound of the school. The second is because the ring cow is in a class A high current state. Extremely easy to saturate and produce hum.
2 In terms of dynamics, transients, and analytical power, it is better to use one 500W cow than two 250W cows. For the sound field, use two for positioning
The independent power supply of 250W cattle left and right channels is better than a single cattle.
3 T2 can use 50W six-lamp machine products with good results.
4 W3 is the filament AC balance potentiometer, adjust its value to minimize the exchange sound.
5 Note that the primary phases of the T1 and T2 transformers must be the same, and the T1 and T2 primary wire ends can be exchanged so that the potential difference between the machine shell and the zero line is the minimum. This is especially important in advanced models where multiple power supplies are used.

School sound:

1 The bile duct can use 6N8P, increase the power supply to + 360V, and the cathode resistance is changed to 1.5K. At this time, the sound of the whole machine is thicker and warmer, the taste of the gallbladder is thicker, and the dynamic is greater. Not on 6N11.
2 Coupling capacitors C1 and C2 are quite satisfactory with Sauron tone and are extremely neutral. With Weimar capacitors, there is less human touch and more realistic sound. Domestic New Dirk capacitors also perform well here. In short, these two capacitors have a great influence on the sound, and different brands will have different performances. You can switch to several different brands and choose the ones you are satisfied with.
3 Transistor is replaced by Sanken tube, which has stronger texture and bright lines, but the tone is harder. Audiophile enthusiasts can use it. After switching to Darlington tube MJ12033, the low frequency after MJ12032 is more plump and sturdy, and the intermediate frequency is also good, but the high frequency is less delicate. Transparency is a little worse, but for fans who use tweeters with frizzy speakers, they may be correct.
4 Using 6Z4 bile for rectification has the effect of increasing bile taste and softening timbre. But it also slowed the bottom of the sound, and it is precisely what has been gained and lost.
The above points are the adjustments of the components that have the greatest impact on the whole machine. The impact of other components such as resistance is not too great. Interested fans can also try it.

After the sound calibration is completed, the machine is continuously burned for about 30 hours, and the working voltage and current are re-tuned. After all are normal, the machine can be listened to.
This is a very neutral sound amplifier. Due to the simplest circuit, the signal distortion is minimized, the reproduction of the sound field, the positioning of the instrument has reached a very high level, and it can be compared with tens of thousands of foreign machines. His voice makes people listen for a long time, both the smoothness of the amp and the fullness and strength of the stone machine. It's not the kind of downsides that favor one's strength by one skill. When the author listens in the listening room,
Even the most discerning golden ear can't pick him out.
Please note that this power amplifier is very sensitive to all equipment. It will give you what sound at almost any price, and will never bury high-priced equipment. Both the bold and timbre sound can be adjusted [such as Marantz 7 preamp + Marantz 16 CD], and the accurate sound effect can also be adjusted [such as with 6N11 SRPP preamp + DENON DCD—S10 IICD].

As users hands or debris enter the zone 6 inches (15cm) from the infrared sensor on top of the dustbin, the lid will automatically open

Rectangular Sensor Automatic Dustbin

Rectangular Sensor Automatic Dustbin

NINGBO ZIXING ELECTRONIC CO.,LTD. , https://www.zixingautobin.com

Posted on