amp wiring question

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capitolj80
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amp wiring question

Post by capitolj80 »

if i've got (2) 4ohm svc's, and i wire them together in parellel (to 2ohms) and hook each to a seperate amp, will the two amps each be running a 2ohm load to their sub or am i missing something? thnx
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Post by stipud »

Umm... you can't wire a single 4 ohm SVC in parallel with itself. You can run two or more woofers or voicecoils in parallel to combine the load, but if you are going to run two four ohm single voicecoil (SVC) woofers on two amps, then each amp will see 4 ohms.
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capitolj80
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Post by capitolj80 »

yeah...it's 2 subs with 4ohm svc's...if i wire them together in parallel, i'll be at a 2ohm load right? i know that if i wired them to one amp id be running at 2ohms, but i wasnt sure if the same would apply if each sub had its own amp
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Post by Bfowler »

sounds like you got it. if each sub has its own amp, it will be putting a 4ohm load on each amp
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Post by fuzzysnuggleduck »

You'd need "strappable" amps to do what you're thinking of but you're still better of going one sub to one amp unless your amps don't produce the kind of power you want at 4ohms... in which case you'd really be better off with some DVC subs instead.
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Post by capitolj80 »

ok...now i sound dumb, but if the two subs wired down to 2ohms on one amp would be a 2ohm load, why wouldnt it be the same if they each have their own amp if each sub is now at 2ohms..is it because the amp share the ohm load? sorry, i just wanna understand how it work :(
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Post by Bfowler »

capitolj80 wrote:ok...now i sound dumb, but if the two subs wired down to 2ohms on one amp would be a 2ohm load, why wouldn't it be the same if they each have their own amp if each sub is now at 2ohms..is it because the amp share the ohm load? sorry, i just wanna understand how it work :(
the first thing to realize (this was the mental hurdle i had to overcome)

is amps do not know how many speakers they are pushing, they only know what load is on them

also, each subs impedance (ohm) can't changes

each sub in this case has an impedance of 4ohms.

when you put them together in parallel, the result of combining their impedance's is the amp sees a 2ohm load.

if you use a separate amps for each sub ,you are no longer combining them, so each amp would see 4ohms
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Post by fuzzysnuggleduck »

capitolj80 wrote:ok...now i sound dumb, but if the two subs wired down to 2ohms on one amp would be a 2ohm load, why wouldnt it be the same if they each have their own amp if each sub is now at 2ohms..is it because the amp share the ohm load? sorry, i just wanna understand how it work :(
Because you'd have two independent amps playing to both woofers.

If you hooked up both subs in parallel and then went to one amp, that amp would see a 2 ohm load, correct. But to correctly connect the parallel-wired woofers to two amps, you'd need to strap the amps together.

Now, I don't know much about this but I'm not sure you can just go and strap any two amps together, especially two different amps. I've been told the Ti800.1 could be strapped as well at the X400.1. From some quick readings it seems like only monoblock amps can be strapped...

Here's what someone wrote at some other site:
Strapping Amps: Strapping is basically joining two monoblock amps together to make one super big amp. Note that not all amplifiers can be strapped. Basically it is like bridging two amplifiers together, so taking the positive from one amp, and the negative from the other. There is a master and a slave amp, the master receives the RCA’s from the H/U and the slave receives from the master…there are switches on them to set what is master and what it slave...there are some amps that rent able to be strapped, but strapping modules can be bought…such as a Crossfire VR2000, but modules such as these can be very hard to come by. Also remember to continually check power going to amps, as strapping can draw a lot more current then you think
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Post by capitolj80 »

ahhh....it all becomes clear now....that's actually a very simple concept...i just couldnt see till u explained it for me...thnx bfowler...im tryin to set my buddy up and he's got these two mono amps (300rms @ 2ohms) and i gotta find him the right sub or subs (he insists on using both amps)....i think im gonna go ahead hook im up with a dual 2ohm sub and just hook an amp up to each voice coil..thnx again dude
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Post by capitolj80 »

and thnx fuzzysnuggleduck too :)
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Post by gkitching »

If you parrallel the 2 subs together, you will only have 1 set of wires to hook up. Which means you can only connect to 1 of the amps.

Some specialty amps can be bridged together creating essentially 1 bigger amp. But unless you have that type of amp, you can't do it.

Now provided your amps can handle a 2ohm bridge, it wouldn't make that much difference between running each sub to a it's own amp @ a 4ohm load verses both subs connected to one amp at a 2 ohm load. Theoretically you will have the same amount of power in either of those cases. It would be more difficult to set levels of 2 amps to be exactly the same. If they aren't, you will have some cancellation issues.

You may want to consider getting dual voice coil subs or 1 bigger amp. of coarse one that can handle a 2 ohm bridge.
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Post by gkitching »

Sorry, you guys type way faster than me.
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Post by HoseHead »

Get two more subs and parallel wire (2ohm) each pair into it's own amp....
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Post by majette »

capitolj80 wrote:ahhh....it all becomes clear now....that's actually a very simple concept...i just couldnt see till u explained it for me...thnx bfowler...im tryin to set my buddy up and he's got these two mono amps (300rms @ 2ohms) and i gotta find him the right sub or subs (he insists on using both amps)....i think im gonna go ahead hook im up with a dual 2ohm sub and just hook an amp up to each voice coil..thnx again dude
you need to level match the amps so that each coil gets the exact same level from each amp. if the coils are not moving together with the same signal level and power they wont last long.
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