Question on Ohms?

[phaseout]

I know this may seem basic to all you audio Genius’s but I’m afraid I’m about to blow all my equipment up. So here goes…
I have a new power amp coming in the mail for me. I want to use it with my existing speakers but I’m confused about the ohm ratings. The back of my speakers has an 8 ohm symbol and a warning stating that I should not use the output on the back the speaker as it may reduce the ohmage (Terminology?) to the speaker, and that this is unhealthy. The new power amp has different outputs at different ohmages (there’s that word is again) but no direction as to select, or make sure you are using the correct setting. Do you kinda see where my question fits in all this?
I’m not asking for a complete lesson on electrical ratings but if anyone knows where I can find this information on-line it would be a big help. I do a lot of playing in my basement but it looks like its time to move on to bigger and better things. Wish me luck

-andrew

[UPCHUCK]

Hi Andrew, here goes a short explaination using some common examples. Lets say that you have four 8 ohm speakers, and your power amp says something like 100 watts @ 8 ohms and 200 watts at 4 ohms. Two speakers can be connected in parallel to halv the total ohms from 8 to 4 ohms. You can think of it like this, if you were running water through a long pipe, there might be too much resistance to get a good flow. If you ran a second pipe in parallel, the resistance would be essintially half, and the out put would be double. So, two 8 ohm speakers connected in parallel will present a load of 4 ohms. Some equipment use output transformers with several taps so that you can select the one closest to the speaker load. If you tried to use more than one of the output taps, you would be in effect shorting out some of the windings. Four 8 ohm speakers in parallel would present a 2 ohm load. Two 8 ohm in series would yield a 16 ohm load. Formula: R1XR2/R1+R2=R TOTAL. OR R1+R2=R TOTAL.

[UPCHUCK]

The formulas for computing the resistance were for parallel connections first, and series second. uc