These are some THD tests I performed of various OPAMPS into a 2.7k load.
Measurement parameters:
PSU: 15-0-15
Gain: 2.2
Output: 2.7V RMS
Load: 2.7k ohms
| OPAMP | THD | Brand | Notes |
| AD712JN | 0.00041% | | |
| AD746JN | 0.00022% | | |
| AD827JN | 0.00036% | | |
| LM4562NA | 0.00016% | | Measurement limit |
| LT1358 | 0.00042% | | |
| NE5532N | 0.00020% | Brand forgotten! | |
| NJM2043DD | 0.00016% | | Measurement limit |
| NJM2068DD | 0.00020% | | |
| NJM2114D | 0.00026% | | |
NJM4558D | 0.00059% | | |
| NJM4565DD | 0.00025% | | |
| NJM4580DD | 0.00017% | | |
| OPA2111KP | 0.00222% | | Note bad harmonics |
| OPA2134PA | 0.00085% | | |
| OPA2604AU | 0.00017% | | |
| NE5532N | 0.00024% | | |
| NE5532 | 0.00016% | | Measurement limit |
| NE5532 | 0.00020% | Signetics | |
| TL072CP | 0.00152% | | |
