Building the lowest noise amplfier circuits can be challenging. For years the good old 5534 (and 5532) were the go-to amps. With their combination of voltage and current noise, they’re right in the sweet-spot for the kinds of impedances typcially used in audio circuits. Sure there are amps with better voltage noise and amps with better current noise, but for the money, the venerable 5534 still performs quite well. Newer amps can best it though, some of our favourites that we now keepin include ADA4898 (an astonishingly low noise amp), OPA1612 – another fantastic audio amp – the good ‘old’ LM4562 (though not as old as the 5532, still been around a while), and OPA2350 for single rail work.