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Comment by squarefoot | Hacker News Reader

Any comments on the LM4562? As per data sheet it appears to be really good for audio wrt noise and distortion, yet I see it rarely mentioned. https://www.ti.com/lit/ds/symlink/lm4562.pdf

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It and the LME49720 (same part) were discontinued a couple years ago along with the entire LME Overture series.

Potential replacements for ultra low THD would be: OPA1612, OPA1656 and OPA1642 with bipolar, cmos and jfet inputs respectively.

There's a massive (old) list of them in Horowitz & Hill TAOE 3e Table 8.3a p. 522. I'm sure you can just go to Digikey or Octopart and do a parameter search for high-voltage, low-noise, BJT-input op-amps too. If one wanted to "use a Ferrari to go the grocery store", they could always use a $20 AD797 or LT1115 for audio applications. :o)

I picked those particular chips is due to their extremely good performance at a reasonable cost. Check their THD against AD797 and LT1115! :)

You sure about the LM4562? I've just checked at TME, Mouser and Digikey, and all of them have many in stock. I's also marked as "nopb" so it could likely be a newer lead free version.

It appears this particular part was un-discontinued in 2021(?). They certainly were all discontinued almost 10 years ago.

https://e2e.ti.com/support/audio-group/audio/f/audio-forum/4... (this list only contains the op-amps, not stuff like the also-discontinued LME49810)

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