Multi Subwoofer wiring - which amp to use? -- Help!!!

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1

Here’s the story, I have 3 subwoofers.

They are all rated at 4 ohms but; one sub is 800 watts, one is 600 watts, and one is 400 watts. (Please don’t ask why :smiley: ) I want to run them all at the same time in my car. How do I safely wire them and what features on the amp do I need to match up with the subs. What the heck does 200 wats X 2 channel really mean?? I am looking to get ~400 watts to each sub so as not to blow the smallest wattage one, is this correct.

I can wire them in parallel and I come up with 1.3333333 ohms total resistance. I would probably want to find a 1 ohm stable amplifier.

Please point me in the right direction in terms of amplifiers which can handle this and/or guides on how to do this on my own.

Thanks in advance for any help!!!

2

OK…so really you want a 400x3…

The 200x2 amp you have means you can split the signal to two speakers at 200 watts a piece or you can bridge the two and run 400 watts to one speaker.

Now, what you can do it run 3 seperate amps for each speaker, or you could buy a very large rates amp to run all three. You would end up needing an amp that runs about 1200 watts…

I would write more, but my head hurts…

Please anyone contradict me if I have said something that was incorrect. Thanks

3

So does that in essence mean that I need a 3 channel, 1 ohm stable, 1200 watt amp???

ooh boy, I don’t think that will be cheap.

Anyone have any suggestions on models that will fit this application?

4

http://www.crutchfield.com/, I buy most of my audio parts there.

Except I broke my car with a 4-wheel drift on the snow:rolleyes:
So now I’ve 2 400watt subs in an enclosure but nowhere to put them.

I’ve borrowed your saying and adapted it some.
Drive it like you stole if, if you can afford to replace it.

Wetzel

I drove it like I stole it.
5

Yeah, crutchfield is good, but it doesn’t carry real high wattage amps. I bought my head unit and all the rest of my speakers from crutchfield, the subs were from e-bay!! yay e-bay!!

edit: will this work?? http://www.salesco.com/amps/akai_aca.htm

Does the 2 ohm stable work with a 1.333333 ohm system?? or does it not matter depending on how I wire the thing, whether in series or parallel?

Sorry to hear about your car too, so the multicolor-mobile is dead now???

6

this will work, but it’s kinda a cheapo…

Because you are running a 1-1.333 ohm system means you can’t run anything lower then that on it. If your amp his a higher resistance rating, the speakers should be fine…

again, please someone speak up if I am wrong…

7

yea that amp is a little cheap, however if it can maintain 2ohms then you should be fine.

a lesson i have learned is that the speakers can take all the power you throw at them, but if you play them too loud with too little power they die.

8

Here we go… I do audio tech work up here at school as a job, and this is what’s the dealio :)…
When you wire speakers in parallel, which is the standard way of doing things so that your phase angle and voltages play nice… ( i’m trying not to explain 6 months of circuits class in 30 lines ) … your impedance goes down.
the relationship is ( R1^-1 + R2^-1 … )^-1 …
so if you put 2 8 ohm speakers in parallel you will get 4 ohms impedance seen by the amplifier, which is what you care about…
Amps will all have an impedance rating, DO NOT EXCEED ( that is, go lower ) it. If you place too small a load
on the amplifier you increase the amount of current which the amp is required to source…
and it gets hot, sometimes stuff melts… :frowning:

The above is probably already known…
The next thing is when you drive a speaker
too loud w/ too small an amplifier your
nice sine wave shaped sounds will
square off at the top and bottom, this is called clipping… and this is what kills speakers. Basically, the cone in the speaker will hit the physical limit and sit there for a bit, and then snap back… that’s bad… its a good way to tear the cones and maybe crack a magnet or 2…

With those three drivers, i’d probably be inclinde to buy multiple amps, i think you’ll be happier, and probably spend less money. Forgetting money for a sec, the
best way is to get 3 amps, one for each, which will cost tons, and you’ll probably need some power distribution stuff for the car power system, like a cap or 2…

:yikes:

More realistically, i’d probably get a 400x2
2 ohm stable and bridge it for 800x1,
put the 400 and 600 on there…then wait to save some cash up for a 600x1 and use that for the 1k driver.
You have options, basically its about how much you want to spend. Last winter we put a 600x1 and a 1200w sub in my friends car,
we had to turn it down so it wasn’t painful…
or drowned out the nice focals he had up front.

9

Thanks all for your help!!! :smiley: :smiley: :smiley:

Second part of my question is, I want this all to possibly end up on our robot cart. What do I need to make it work as a stand alone system. I would like to have this done for our NYC regional which is in about a month. But… If I actually need to invest a little more planning in it then I might just scrap it for later in the season.
So you all know I have the subs in a box already, I would probably need a head unit and a seperate battery to power it all right?? Thanks for all the input, please be patient with me.
I have been an audiophile prolly since the mid 90’s but have no idea on how to do the technical stuff that goes behind it!! I’m a CAD guy not an Electronics guy!!! lol

10

Sound-motion powered cart?

Yeah, a souce(head unit) and power(battery) are needed. Don’t you have any electronics people on your team to help?

Beware the rules on loud music in the pits.

Wetzel

I drove it like I stole it and broke it.