First off thanks in advance for any help. I have installed a Sundown Audio SAX-125.2 amp and connected it to some older Boston Acoustics 6.5 pro series components in the front doors. The rears are Kicker DS693's that are running off the front channels of the oem base stereo. I am hoping to be able to run all 4 off of the amp in parallel without damaging anything but I need help figuring out impedence and wattage. Here's the stats that I know.
Amp : rms power, 4ohm stereo = 125w by 2ch
rms power, 2ohm stereo = 200w by 2ch
6.5 Pros : 3ohm and not sure rms wattage
Kickers : 4ohm, 70w rms/140w peak

I'm thinking that the ohms "seen" by the amp will be around 1.77ohms but is that to low to be safe? At that what will the watts be being sent to each speaker?
I purchased this amp when I had the S2000 because it was highly recommended on S2ki.com because it runs so cool.

 

Sundown makes good gear, but your best bet will be to sell this amp and get a 4 channel.

Boston speakers are at 3 ohm to get a bit more power out of the amp source. Mostly marketing gimmick. But it does throw a wrench in series/parallel wiring...

If you want to use the amp, try running them in series to up the resistance closer to 8 ohms. Your power output will go down, but the amp will be safe.

You *may* get away with running down under 2 ohms, but the amp may go into protect and shut off, or just not turn on.

Besides, there are several quality amps that are smaller, and will run cool, without the worry of losing your fade control, and provide plenty of power.

 

you should be safe... as the speakers move so does the impedance, it will change like 200+ times a second... I connected a D2 (parallel) sub to my 2ohm stable amp for a few months without any hurt to the amp... if you are unsure do a test to check the heat coming from the amp, if it gets too hot just un connect it or sale it and get a 4 chan.

 

So based on my amps specs what kind of wattage would it be pushing to each channel?

 

the best way to figure that out would be to do a clamp test with a multimeter/clamp ammeter (true RMS) and play test tones or pink noise that covers the frequencies you are trying to amplify one by one ( pink noise would be better due to the stress test tones put on the amp)... you will never constantly see max power from any amp due to impedance shifts.

 

Not to be a smart *** sbeezy but I'm just a noob to all this. Not so much a noob but in no way an electical engineer. Isn't there a formula or something based on the specs that I posted in the first post that calculates expected wattage? i don't know anything about pink noise or impedance shifts. Just sayin.

 

First, look up the Boston specs online and find out the RMS rating. My recommendation is to meet or slighty exceed that RMS rating in your amplifier, assuming you want to get some sort of lifespan out of your speakers. Same thing goes for the rears. For example, the Boston's may say the RMS is 100 watts at 4 ohms per speaker. So you'd know that that a good amp match would be 100-110 watts per channel at 4 ohms, like a 100wattx2 amp into 4 ohms.

Dump that amp and get something that matches your speakers in a four channel, 2 channels for the front and 2 for the rear.

No offense to any of the previous posters but you're making it a lot harder then necessary for a newbie.

 

E = I * R

P = I * E or I(squared) * R

Where E = voltage, I = current measured in amps, R = resistance measured in ohms and P = power measured in watts.
Then you get into 'impedance', which is what an amplifier expects to find when it looks at a speaker, symbolized by the letter Z and a whole new set of formulas.

So, based on all that, 1.77 ohms of impedance is dang near a dead short which as we all know can fry a circuit. Your amplifier will be producing a lot of heat.

 

It's all good we have to start from the bottom... I started with car audio at the age of 6 when I asked my uncle what made his car boom boom...
Www.pwkdesigns.com/forum
www.diyma.com
I am a member of both forums there are lots of guys here on these forums who can lend advice and you might find someone close to you to help.
another thing you can do is contact Jacob (the owner of sundown) he is very helpful and can give you the best advice as this is his baby.