On Sun, 8 May 2016 18:28:08 -0700 (PDT), wrote:

why are stereo equipment fuses glass tubes in cylindrical holders,
auto fuses in vinyl holders fuses set in plastic cases with 2
connecting prongs out the bottom. ?????

1. Glass and ceramic cylinderical fuses have the fuse wire soldered
to the end caps. If you were to do the same thing using a plastic
tube, the heat from the soldering operation will melt the plastic
tube.

2. Automotive style plastic fuses, also known as blade or spade
fuses, use a stamped fuse wire. You can only make a stamped wire so
thin before it falls apart. The minimum value I could find for
cartridge fuses is 0.080A. The minimum value I could find for
automotive fuses is 1 amp:
http://www.littelfuse.com/products/fuses/automotive-passenger-car/blade-fuses.aspx
Speaker protection fuses need to be fairly low current:
http://www.barryrudolph.com/greg/fuse.html

3. Glass and ceramic cylinderical fuses are typically rated at 117
and 230VAC insulation. Plastic automotive fuses are 32v and 58v. Note
that it is possible to obtain UL listed blade fuses:
http://www.optifuse.com/blog/p100201.php
but not for use at 117/230VAC.

4. For stereo equipment, glass fuses can be chrome or gold plated to
make them look "cool" and expensive. Same with gold and chrome plated
cartridge fuse holders. Plastic fuses are comparatively ugly.
https://www.google.com/search?tbm=isch&q=gold+audio+fuse

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558