Capacitor Types

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My capacitor recommendations:
470pF and below: silver mica or MLCC. Silver mica is better, especially in the signal path. They are wider, so fitting is sometimes difficult.
470pF to 1uF: film except when MLCC or electrolytic are specifically called out in the build docs or PCB silkscreen.
1uF to 47uF: tantalum electrolytic. Tantalum caps are far superior electrically (and more expensive) compared to aluminum.
above 47uF: aluminum electrolytic.

I have been searching on tantalum and have some questions based on the above. When you are designing a new circuit on a breadboard or in Spice, and have a 1uF cap from the output of an op-amp in-line to further processing (not to ground), do you use film or tantalum?
Or only use tantalum in an actual build, not on a breadboard, due to noise?
If tantalum is far superior, does it make sense to use it whenever a 1uF cap is needed in the signal path?
Does tantalum have a lifespan issue like aluminum electrolytics?

 

[Chuck D. Bones]

In general, I consider 1uF film & 1uF tantalum to be equivalent. In theory, film caps are less noisy than tantalum because their leakage is lower. However, the leakage in tantalum is so low that I doubt the noise will be detectable. Some hard-core audiophiles might be able to tell the difference under optimum listening conditions.

If the capacitor must be non-polar, for example in certain oscillator circuits, then film is necessary.

On the breadboard, I use whatever comes to hand.

On a PCB or Vero, I use whatever fits.

Tantalum caps DO NOT have the limited-life problems that plague aluminum caps. Provided they are not over-stressed, tantalum caps will be among the most reliable components in your circuit.