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say if i paralled 2 16 ohm speakers and 2 8 ohm toge ther speakers what ohm load would I have on this mono amp???

Long Lost Brother wrote:say if i paralled 2 16 ohm speakers and 2 8 ohm toge ther speakers what ohm load would I have on this mono amp???

Since you are talking about a parallel circuit, you would need to know the amps and the voltage being fed through them... Once you figure those out, then, There's a formula to solve for the total resistance...

http://www.tpub.com/neets/book1/chapter3/1-26.htm

oh boy!! that was trippy. See ive got these two 16 ohm Peavey speakers that I would like to daisy chain with these two 8 ohm Yamaha Monitors, but I want to be sure that I font drive that mono mackie amp below 2 ohms

Daisy chain - series or parallel? You need to know how the wiring is in the speakers. If its parallel, 2 16 ohm speakers together will give you 8 ohms.

2 8 ohm speakers in parallel will give you 4 ohms. Combine all of them in parallel and you will give you 3 ohms.
The formula is: (R1 + R2 + R3 + R4)/(NxN) Where R = resistance of each speaker and N = number of speakers.

If any are in series, then the resistance just adds cumulatively. If you dont' understand parallel and series wiring, get someone who does to look at your setup!

If they are Peavey speaker enclosures they are most likely 8 ohm mine are. Which brings the Peavey speakers to 4 ohm. I am unsure about chaining miss matched ohm speakers to One power amp. It doesn't sound like a good idea to me. I do know that if you put too much load on most power amps they will overload and shut down without doing damage to the amp itself. We had that problem with QSC back in the 80's at a gig. We were asking it to do too much and it kept shutting down (in the middle of a song)! During a break we took the miss matched speakers off and the rest of the gig went fine.

lol Yeah I was thinking that, I just didn't want to be the one to say.

I wouldn't connect different impedance speakers AT ALL.
(you smell something burning?) lol

Make sure you ask someone who really knows the whole story.

You could call Guitar Center or Sam Ash and I think they would help you.
(for free even)

A two ohm system will handle all this and then some.

You run four 8 ohm speakers @ 2 ohms.


If you amps will handle unbalanced loads you can run different ohm rating with no problem as long as the total is not below the amps rating.
I do it every day.

Be mindful of the wattage however or you can blow the lower rated speakers.

I've been running 16 ohm hotspots with an 8 ohm 200 watt monitor for years with no issues.

I also prefer 2 ohm amps in my rolling rack ... they are more versatile as they can be safely operated anywhere from 16 - 2 ohm.

It allows me to vary my speaker array and match wattage to my venue.

I'm no sound pro.
But I know it works for us by experience.

You taught me something George Thanks!

Long Lost Brother wrote:say if i paralled 2 16 ohm speakers and 2 8 ohm toge ther speakers what ohm load would I have on this mono amp???

The short answer: 3.2ohms.

The longer answer: You will be sending twice as much music energy (current) through the 8ohm speakers so they will be 3db louder if all other specs are the same. Your 2ohm rated amp will survive as long as you don't clip it to death but this is probably not an ideal setup.

For example: If your amp produces 900w @3.2ohms you will be sending 300w to each of the 8ohm speakers and 150w to each of the 16 ohm speakers at clipping. This works well if you mix 16ohm Hot Spot (near field) monitors with 8ohm floor wedge monitors as George suggested. It is less effective when mixing mains and monitors. I usually want a different amp to drive each.

That's why this forum is nice, the people that know tell you and tell you why.

Thejohnny7band wrote:

Long Lost Brother wrote:say if i paralled 2 16 ohm speakers and 2 8 ohm toge ther speakers what ohm load would I have on this mono amp???

The short answer: 3.2ohms.

The longer answer: You will be sending twice as much music energy (current) through the 8ohm speakers so they will be 3db louder if all other specs are the same. Your 2ohm rated amp will survive as long as you don't clip it to death but this is probably not an ideal setup.

For example: If your amp produces 900w @3.2ohms you will be sending 300w to each of the 8ohm speakers and 150w to each of the 16 ohm speakers at clipping. This works well if you mix 16ohm Hot Spot (near field) monitors with 8ohm floor wedge monitors as George suggested. It is less effective when mixing mains and monitors. I usually want a different amp to drive each.

Absolutely ...
Though my in my head math did not come up with 3.2 it was obvious it was an acceptable load.
And I fully agree on the mains.
We are operating on four mains at present. Two 8ohm 400 watt Peavey 15" two ways right in front of us. I put feet on one side and lay them down AKA monitor position facing audience center.
Each is connected to a separate 500 watt 2ohm capable amp. The input is fed through to two 750 watt 4 ohm capable amps that run my three way Carvin dual 15" towers that I set to right / left of stage with the field of throw slightly overlapped at audience center.

an excellent guide to understanding audio set ups.
http://www.bcae1.com/

the calculators give a load of 2.667 Ohms

JCP is right 2.67 ohms instead of 3.2. That is what happens when you do these things in your head instead of using a calculator. Both are considered a safe load for a 2 ohm rated amp. Your amp will just run a bit warmer and use a little more electricity than my original figure. You only want to run this speaker load with a 4 ohm rated amp if you are planning a barbeque and ran out of charcoal.

Wow, it' s been a long time since I took electronics in college.

Te3h correct formula for resistance in a parallel circuit is:

The total resistance of a set of resistors in parallel is found by adding up the reciprocals of the resistance values, and then taking the reciprocal of the total:

equivalent resistance of resistors in parallel: 1 / R = 1 / R1 + 1 / R2 + 1 / R3 +..

So 2.67 is the correct answer (I guess my first formula approximates it!)

It can get trippy or you can KISS method.

A 2 ohm amp will safely operate the equivalent of four 8 ohm speakers.


Maintaining speaker rating appropriate wattage is necessary for safe operation and your best sound output.
For most of us with what by professional standards are simplistic set ups.
This is enough to keep in mind.

Seems most PA ( monitors & mains ) speaker cabs are run in parallel.
Not necessarily so with cabs intended for instrument amp applications.