Audio Systems: car amp to home system, impedance load, speaker impedance

Question
recently i got my hands on a few different subwoofers and speakers, so i decided to hook them up to my jvc home system i already had the stock speakers hook up and added 2 other jvc speakers a aiwa home subwoofer that get power from the wall and a set of 2 6" subs in a box, but i relized that when i turn it all on it all work well, but when i turn it up to a certain volume it every thing stops playing music but the home sub now i think it because there is too many amps going to my head unit i have car amps but i was wondering if it was possible to hook one up to my home system i have a american legacy seriesLa890 series 2, 4 channel 1200watt amp can you please help me out...? i would greatly appreciate an educated oppion thank you

Answer
You have two problems.

ONE:  Adding speakers in parallel is a dangerous thing for the amplifier.  If the impedance of the amp is rated at 4 ohms, for example, you must never load the amp with a load of less then 4 ohms.  If you have connected the the amp a 4 ohm speaker it is fine.  When you add another speaker to that amp the impedance load becomes 2 ohms and that will be dangerous to the amplifier.  Therefore, you must make sure you are properly loading an amplifier with speaker impedance suitable for the load ratings of that amplifier.  In your example situation you have added too many speakers and overloaded the amp; it was sent into protection mode - and maybe damaged internally.

TWO:  You want to use a car amp in the home.  The unit you mentioned is bridgeable and is suited for a 2 ohm loading scheme.  It can drive speakers nicely being with much power.  Here is a good site for deciding how to wire speakers to it for proper loading:

http://www.crutchfield.com/S-wb8DkpFeMsz/learn/learningcenter/car/subwoofers_wir...

and choose from the various configurations given at the bottom of that page.

Then your next big hurdle is how to power the amplifier when used in the home.  It is never a good solution and I don't recommend you do it.  The only practical way to power it is either a car batter/charger combination or a 12v converter power supply.  Either one of which, to supply the enormous current this amp requires, will cost more than to just purchase a home amplifier.  It is not a good solution ever to run a car battery in the home.  Under severe conditions like this amp would place on it the battery could explode and cause all kinds of dangerous liquids to spray around the house.  

Let me know after studying these ideas if you have more questions.

C