There's one thing that needs to be clarified "between" tantalum and electrolytic caps..
Electrolytic and tantalum are not mutually exclusive terms.
Just copying the text here for any future reference:
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Capacitors may be:
polar or non-polar
electrolytic or non-electrolytic
aluminum or tantalum
Ceramic, mica, mylar, polyethylene , polypropylene, aluminum, tantalum, etc. are materials used in the construction of the capacitor. Specifically, it refers to the dielectric material that separates the parallel plates of the capacitor. The material could be a solid, liquid or gas. A liquid electrolyte is often used and hence the term electrolytic capacitor.
Electrolytic capacitors made with aluminum (or aluminium) are generally lower priced than those made with tantalum.
Tantalum capacitors have higher capacitance per volume.
Capacitors made with tantalum can be either polar and non-polar though the polarized form is more common.
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I replaced 4 tantalum caps on my preDMD WPC89 audio board with electrolytic 1uF/50V (same value) and they still work.