some more links & details from my pervious emails here from 2001 & 2002Hi
There are some good articles on the web about the wiring as I recently
reconnected mine. The Hanes manual's wiring diagram was wrong by the way
in case you look at that.
The factory wiring has the speakers (4ohm each) connected in parallel,
this results in a 2 ohm load across the amp for each channel. And most
amps can't handle such a low load for a long time, the result could be
cooked output transistors. If you have an after market external amp you
may get away with it as many are rated down to 2 ohms. Otherwise you
need to connect your speakers in series so that they have an 8ohm load.
The result is they are not as loud but they still work just fine.
Anyway check
http://www.miataforum.com/cgi-bin/ultim ... 7;t=000099
http://www.mx5club.org.nz/emaillists/nz ... g00107.sht
http://www.mx5club.org.nz/emaillists/nz ... g02555.sht
(yes my site search engine is still stuffed... I found them via google
using a search for "headrest speaker howard site:mx5club.org.nz"
zorruno