On the Collocation of Integrated Operational Amplifier and Integrated Power Amplifier

Into the op amp and integrated amplifier is the primary enthusiasts and students enthusiasts favorite use of two types of devices, they are many varieties, different performance, sound quality and sound and different. How to combine the above two types of devices, combinations, to make the best use, to play their respective advantages, to create the best cost performance, is a question worthy of discussion.

I have a few years of fever, although the accumulation of some experience, but also inventory a considerable number of audio devices. Which integrates a large number of integrated op amp and integrated amplifier, including the early fever op amp LM833N, NE5532N, NE5535N and the recent hot OP275G, LT1057, AD827JN. Integrated amplifier is a very well-known models, such as TDA1514A, LM1875T, LM1876TF, LM3886TF and early TA2030A. Of course, like JRC4558P, TL072 and TDA2030 these models of the block, because its performance is not enough "fever" level, they do not have to come up with research.

Above the integrated power amplifier is done a finished board, board components, the process is quite elegant, and are very simple. For the above-mentioned several op amps, because the standard dual op amp, so only a piece of front buffer amplifier board, is June 13, 1999 "newsletter" on the "fine 1876" AD827 with the piece The Components are very elegant: DALE W gold film resistors, WIMA, ELNA capacitors, APLS potentiometer, silver-plated double panel, the process is also very sophisticated. I removed the AD827, put on a 24K gold-plated operational amplifier socket.

As for the power supply, op amp with servo power supply ± 15V power supply, power amplifier is a large ring cattle, double bridge rectification, large reservoirs and small reservoir electrolysis power supply.

I also invited a few like-minded Shaoyou friends, the common taste. Listening time is still selected after 7 pm, the purpose is to have a better environment. The equipment used to build a new third generation DVD8058A and Huixi Du Xi 2  1C, the software is still familiar with the saxophone, Tsaiqin old song, Hugo Ⅰ and so on.

I love 1876, let it lead the array, followed by it put on the aforementioned six op amps. Of course, the author previously used the 827 +1876 combination of listening to the best, won the praise. This match with the high frequency of a strong music taste, smooth, balanced, natural, warm, people intoxicated, low frequency is also neat, retractable. OP275 +1876 combination of high-frequency extension in the slightly worse, slightly slightly blurred low frequency, IF is still excellent, the overall feeling slightly lost in the AD827, is the pursuit of cost-effective choice. LT1057 Although the famous, but with the 1876 with not appropriate, the problem lies in the sound, always giving "cold", "thin" feeling. LM833 and NE5532 similar, sound warm, but high-frequency burr strong, low frequency also can not accept the end, 5532 noise is still slightly larger. As for the NE5535, put on a channel after a serious distortion, it is estimated that the damage, then withdraw from the contrast. In summary, for the LM1876 this amplifier, with AD827 can achieve the highest performance, and with OP275 is a cost-effective.

Then we put LM3886, it feels very similar with the 1876, and more power. With the AD827 still feel better. OP275, NE5532, LM833 these three after the difference is not, but OP275 low frequency is better, it may be related to its 22V / ms conversion rate. LT1057 still reflects the characteristics of the metal flavor, this combination makes people feel good for home theater, dynamic, momentum enough. In particular, "Hugo I" in the "picture exhibition" of the [Kiev door] section, very majestic.

In the LM1875 this prestigious amplifier, AD827 is not very prominent, LT1057 people make a shock, the overall balance, sound moderate, high and low frequency rich, the details of the music is also handled just right, especially Kenny G Sax "spring" Background music triangle iron accompaniment, particularly clear and pleasant, the slightest deduction. NE5532 and OP275 with 1875 is also good. Especially 5532, can be described as cheap, it has the same conversion rate with 1875, no speed "bottleneck" problem, make the best use, it is recommended, LM833 is slightly worse.

For the 1514A, because it is a "cool" type amplifier, and LT1057 difficult to get along, several other op amp in the AD827, OP275 better. NE5532, LM833 can also be used with, but IF is always not satisfied. Comprehensive consideration, the 1514A, OP275 can be preferred, although no prominent place, but also quite satisfactory.

The final appearance of the TDA2030A, although it is yesterday's yellow, but the community has a large, and quite a part of the computer active speakers still use it, our proposal can be used as a reference for 2030A users. We recommend using the NE5532 or LM833, they are enough with 2030A, there is no need to pursue the other three. From the sense of hearing, the difference is minimal.