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Based on what I'm reading here, this chip may be great in certain specific uses, but apparently it isn't the sort of thing folks can just pop into their DIP socket.
Totally agree; also the way you decouple the OPAMP, the type of capacitors and where they are physically located around the OPAMP makes the difference.
For example, decoupling the LME49720 (aka LME4562 - same die) with 0.1uF Film cap can give it a harsh sound in the mids and make it sound a little bright IMO.
Go back and change the capacitors around the circuit to something like 100nF (0,1uF) Multilayer Ceramic Capacitors (MLCC) (such as AVX SR205C104JAR) in parallel with 470nF MKT Film cap (such as EPCOS B32529C474J) I found the timbre or tonal character of the opamp to change quite a bit.
I also quite like the combination of a 4,7uF 35V Tantalum (such as AVX TAP475K035SRW or VISHAY / SPRAGUE 199D475X9035C6VE3) in parallel with 1uF MLCC (such as AVX SR305C105K or MURATA RDER71H105K2K103B) is quite a sweet sound with the LME49720.
If your using the AD797, this requires care when decoulping, it seems to work best with 100nF MLCC capacitors that are bypassed with 4,7uF 35V Tantalums that have a further 1,0 Ohm resistor in series with the 4,7uF cap - there is good reason for this to dampen the ESL (Lead Inductance) of this cap.
The AD Datasheet gives a lot of good pointers in using this fast OPAMP.
Also a 10nF MLCC cap across the +V and -V supply rails at the chip (you can solder it on top of the DIP package's PINs) tends to keep it under control, as well as the usual decoupling from +V to GND and -V to GND, as described above. The following gives an outline:
D1 and D2 are a good idea if your using two 9V Batteries to run the circuit - they prevent the opamp from destroying itself...esepcially if you try and run the opamp with, say, the -V Battery disconnected. A schottky such as the 1N5817 is useful for the more sensitive MOS devices.