Talking about the collocation of integrated operational amplifier and integrated power amplifier

The operational amplifier and integrated power amplifier are two kinds of devices that beginners and students like to use. They have many varieties, different performances, and different sound quality and color. How to match and combine the above two types of devices in order to make the best use of them, give full play to their respective advantages, and create a priority cost performance ratio is a problem worth discussing.
Although the author has accumulated some experience in the course of fever for several years, he also has a considerable amount of audio devices in stock. There are many integrated operational amplifiers and integrated power amplifiers, including the early feverish operational amplifiers LM833N, NE5532N, NE5535N and the recently popular OP275G, LT1057, AD827JN. Integrated power amplifiers are some well-known models, such as TDA1514A, LM1875T, LM1876TF, LM3886TF and earlier TA2030A. Of course, modules like JRC4558P, TL072 and TDA2030 do not need to be studied because their performance is not high enough.
The above integrated power amplifiers are all finished boards. The components and processes on the boards are exquisite and simple. For the above-mentioned op amps, because they are standard dual op amps, only one pre buffer amplifier board is used, that is, the AD827 in Detail 1876 on the Electronic News on June 13, 1999. The components are very sophisticated: DALE W gold film resistor, WIMA, ELNA capacitor, APLS potentiometer, silver plated double-sided plate, and the process is also very excellent. The author removed the AD827 and replaced it with a 24K gold plated operational amplifier socket.
As for the power supply, the op amp is powered by ± 15V servo power supply, and the power amplifier is powered by a large loop cow, a double bridge rectifier, and a large pond electrolysis in turn.
At the same time, the author also invited several like-minded barbecuers to comment together. Listening time is still selected after 7:00 p.m., so as to have a better environment. The equipment used are Xiaxin's third generation DVD8058A and Huiwei Dushi 2.1C, and the software is still familiar with saxophone, Cai Qin's old songs, Hugo I, etc.
The author loved 1876 and let it take the lead, replacing it with the aforementioned six operational amplifiers in turn. Of course, the combination of 827+1876 used by the author before gave priority to the sense of hearing, which was well received. This medium and high frequency matching has a strong musical flavor, which is smooth, balanced, natural and warm, making people intoxicated. The low frequency is also clean and easy to play. The combination of OP275+1876 is slightly poor in high-frequency extension sense, slightly vague in low-frequency, and still excellent in intermediate frequency. The overall feeling is slightly inferior to that of AD827, which is the first choice for pursuing cost performance. Although the LT1057 is famous, it is not suitable for matching with the 1876. The problem lies in the timbre, which always gives people the feeling of "cold" and "thin". The LM833 is similar to the NE5532. It has a warm voice, but it has a strong sense of burr at high frequencies. At low frequencies, it can't stop the tail. The noise of the 5532 is still a little loud. As for the NE5535, one channel is seriously distorted after replacement, which is estimated to be damaged, so the comparison is withdrawn. To sum up, for LM1876 power amplifier, AD827 can achieve high performance, while OP275 has high cost performance.
Next, we replaced the LM3886, which is very similar to the 1876 and has higher power. I still feel better with AD827. The OP275, NE5532 and LM833 have little difference after use, but the low frequency of OP275 is better, which may be related to its 22V/ms conversion rate. The LT1057 still reflects the characteristics of heavy metal taste. This combination makes people think it is good for home cinema, with great dynamic and momentum. Especially the section [Kiev Gate] of the Picture Exhibition in Hugo I is very magnificent.
On LM1875, this prestigious amplifier, the AD827 is not very prominent, while the LT1057 is a shock. It is balanced as a whole, with moderate timbre, rich high and low frequencies, and the music details are handled properly. In particular, the background music triangle iron accompaniment in Kenny G. Sax's Spring Wind is clear and pleasant outside the frame, and it is perfect. The NE5532 and OP275 match well with the 1875. In particular, the 5532 is cheap and good in quality. It has the same conversion rate as the 1875. There is no speed "bottleneck" problem. It makes the best use of everything. It is worth recommending, while the LM833 is slightly worse.
As the 1514A is a "cool and beautiful" amplifier, it is difficult to get along with the LT1057. The AD827 and OP275 in other amplifiers are better. The NE5532 and LM833 can also be matched with them, but the IF is not always satisfactory. After comprehensive consideration, 1514A and OP275 can be the first choice. Although there is nothing outstanding, they are still in line.
The TDA2030A, which was later unveiled, although it was yesterday's yellow flower, has a large number in the society, and a considerable number of computer active speakers still use it. Our suggestions can be used as a reference for 2030 A users. We recommend the NE5532 or LM833, which is enough to match with the 2030A. There is no need to pursue the other three models. In terms of listening sense, the difference is negligible.