PA Help!!! Ohms, Watts, Peak, RMS, Bridged???

[Robertt8]

okay, i'm confused beyond belief when it comes to this whole Ohms thing...not to mention wattage thing between peak and all that when it comes to PAs and Speakers

what does all this mean for a PA?...

• 200W peak @ 8 ohms
• 400W peak @ 4 ohms
• 100W RMS @ 8 ohms stereo
• 175W RMS @ 4 ohms stereo
• 450W RMS @ 4 ohms mono-bridged

and how do i know if i'm using 4 ohms or 8 ohms or what? what is bridged, and how do you even do that?

man am i lost with this stuff!

[AlexW]

The ohm ratings apply to the speakers your hooking up to the power amp, essentially the load placed on the amp by the speakers. At a lower rating, the resistance is less, so you get more power draw. Here's some good general info on power amps. The site also has some good articles regarding hooking up speakers.

http://www.colomar.com/Shavano/poweramps.html

[Ed Dixon]

Ohms refers to the impedance of the connected speakers, measures in ohms. Most speaker cabinets are 8 ohms. If you connect two cabinets together to the same channel, the result is 4 ohms. Most cabinets are labeled on the back.

Watts is the power output of the amplifier. RMS is the best measure of the output as that is more reliable than peak power, which cannot be sustained.

Most amps can put out more power for lower impedance speakers. If an amp does 100W at 8 ohms, then it would generally put out more power for 4 ohms, sometimes roughly double.

Mono-bridged refers to using both amp channels to drive a single set of speakers. In this case the output power for the two channels is bridged together for a single set of speakers.

There are lots of other details, but that is the basics. Google is a good source for more info.

Ed

[Robertt8]

hey! those are some great articles on that guys site. thanks!

[fenderdude]

What about hooking up speakers in series or parallel? I have heard that most new speakers are internally wired in parallel so even if you are hooking them up in "series" you actually get the benefits (or not) of hooking them up in parallel? I haven't found much on this topic any ideas about the internal wiring or if this is even correct?????

[Adam P]

Check out these two posts by "boingoman"...tons of very helpful info, and easy to understand.

http://homerecording.com/bbs/showpos...2&postcount=10

http://homerecording.com/bbs/showpos...6&postcount=14