Purchased two op-amps.
Hello, I'm Munou.
I lent a digital amplifier I bought a long time ago to a friend, and I'll probably just give it to them, so I bought a new digital amplifier and op-amps.
The digital amplifier will arrive at the end of this month, so I'll write about it then.
This time, I'll properly research the op-amps I bought.
LME49720NANOPB
Originally, I planned to buy one made by Burr-Brown, which I used before, but there wasn't much stock, so I decided to try another brand.
Current TI, Texas Instruments, has made many acquisitions, so while it's manufactured by TI, it's produced under the National Semiconductor brand.
https://prod.kyohritsu.com/KP-LME49720NA.html
>Flat-balanced monitor sound
Customize your preferred sound by replacing op-amps! This is a set of op-amps for audio, original to Kyohritsu Products. It's a Hi-Fi audio op-amp boasting low distortion: 0.00003%. It's popular for DIY headphone amplifiers, etc. 600Ω Easy Drive.
https://www.ti.com/product/ja-jp/LME49720/part-details/LME49720NA/NOPB
>Overview of LME49720
The LME49720 device is a product in the ultra-low distortion, low-noise, high-slew-rate op-amp series, optimized and fully specified for high-performance Hi-Fi applications. Combining advanced modern process technology with state-of-the-art circuit design, the LME49720 audio op-amp driver achieves unparalleled audio performance as an excellent audio signal amplifier. The LME49720 can easily meet the demands of the most stringent audio applications by combining very low voltage noise density (2.7nV/√Hz) with almost negligible THD+N (0.00003%).
Apparently, it's installed in the following product.
https://hifigo.com/blogs/news/upgrade-desktop-dac-topping-d70-bt-comes-with-bluetooth-hifigo
Since it's manufactured as other chips and products, a simple comparison isn't possible, but it seems to be installed in amplifiers costing over 50,000 yen, so I'm interested.
NJM2068D
JRC, New Japan Radio's op-amp.
https://www.nisshinbo-microdevices.co.jp/ja/products/operational-amplifier/spec/?product=njm2068
>The NJM2068 is a dual op-amp with low noise, high speed, and wide bandwidth. Compared to the NJM4558, its SR, GB, and noise characteristics are further improved. It incorporates a phase compensation circuit and can be widely applied in audio equipment such as active filters and audio preamplifiers, as well as for industrial measurement. Additionally, for applications requiring low noise, input-referred noise voltage selected versions (NJM2068DD/MD/LD) are also available.
Although it states a low distortion rate (0.001%), which is a larger value than the LME49720 mentioned earlier, the measurement methods of the manufacturers might also differ, so I feel this level is just within the margin of error.
Because it seems to be somewhat complex.
Ask an Applications Engineer – 13 Why Are Op Amp Distortion Specifications So Complex?
Although I couldn't find this product or an amplifier equipped with it, I have some expectations since it's my first New Japan Radio product.
I recall seeing in a documentary long ago that wireless equipment from a certain country that often launches missiles was Japanese-made. (I don't know if that's true, and I don't think op-amps are very relevant, though.)
When the digital amplifier arrives at the end of the month, I might post again after making some modifications.
I have spare 8-pin sockets at home, so I'll make the op-amps swappable.
See you then.