sub amp wiring ops. ohm and watt, how does ohms relate with watts? expert needed Options

[urbandork]

Assuming im using dvc subs that have an rms of 250w


what 4ohm load amp would i be looking at wattage wise???? would it be 250 watts RMS x 1 bridged output at 4 ohms. or would it be 500w?


what kind of mono and or 1ohm amp would i be looking at would i need it to be 250 at 1ohm or 500???

I get the sub and stuff but how does wiring of the subs in parallel and series as well as ohm at amp to ohms at subs affect the wattage being put out by the amp.

Last but not least which of these two wiring options should i go with????

This post has been edited by urbandork: Dec 26, 2005 - 3:47 PM

[mikew04]

Are the subs 4ohm DVC? I'm assuming so because of the diagram you put it. Do realize that any amp running at a 1ohm load (which most amps are not capable of) will be running very hot and distortion will be considerably higher than a 2 or 4ohm load. Did you already purchase these subs?

If you did not, and you want to run 2 subs, then I would get (2) 4ohm single voice coil subs, wire them parallel, and hook them up to an amp that is stable under a 2ohm load, and puts out around 500rms watts at 2ohms.

Alternatively, you can get (2) 2ohm DVC subs and wire them like this:


If you already purchased the subs, and they are 4ohm DVC, then you can use either of the wiring diagrams you posted. Personally, I would find an amp that puts out 500rms watts at 4ohms and wire the subs up to it like in your first diagram.

Generally, an amp will put out more power (but run hotter and have an increase in distortion levels) the lower the ohm load. However, many amps that are stable down to 1ohm will not have any power increase over 2ohms. If you are not going for an audiophile sound system, try in run the subs at 2ohms, that way you won't have to spend as much on the amp.

[urbandork]

nope havnt bought n e thing yet

but i plan on running two infinity refrence 10 inch. dvc 4ohm. and i need to figure out what amp i should use.

i was thinking about this
http://www.crutchfield.com/S-HiCh6oqnMs8/c...120&I=108R7521A
or
http://www.crutchfield.com/S-HiCh6oqnMs8/c...=120&I=108R611A

which one of these should i use
http://www.crutchfield.com/S-HiCh6oqnMs8/c...nfinity#see_all


with two of these
http://www.crutchfield.com/S-HiCh6oqnMs8/c...=520&I=1081040W

btw i chose these subs becaus my encloser is really small.

This post has been edited by urbandork: Dec 26, 2005 - 10:49 PM

[ShadowFX]

you cant use the first amp, that will only be stable for 4ohm bridged.

the scond amp is stable down to 2ohm, and would not be able to be run at 1ohm (safely). imho i think you should go with 2 x 2ohm DVC subs, wire the sub voice coils in series, and then the subs in parallel to the amp, like mike said above.


Actually looking at the sub, these are 4ohm SINGLE VOICE COIL subs. so 2 wired in paralell would create a 2 ohm load at the amp. so perfect for the mono amp.

[urbandork]

why cant i use the first one.

The first amp puts out a stable 4 ohms bridge and if i use the wiring diagrams for the 4ohm dvc subs then i need a amp that puts out a 4 ohm load

[RocketScott]

It's not that the amp "puts out" 4ohms it's that it can handle a 4ohm load. The first amp would work but it wouldn't give you enough power. I should say it won't provide near as much and two of the subs can take. Those subs have a working range up to 250W. The first amp will only give each of them 97W. This amp will put out 278W to each one and is $50 less (granted, it is factory reconditioned):

http://www.crutchfield.com/S-1szqrVLe6p5/c...120&I=698R7540A

The mono amp you chose is way more power than you need, 670W. It won't kill the subs and if you plan on upgrading later it might be a good buy. If you don't plan on buying any more subs then it might be overkill.

[ShadowFX]

saying it again, these subs are SVC. they are 4ohm single voice coil subs.



1 pair of terminals.. single voice coil.

[RocketScott]

saying it again, these subs are SVC. they are 4ohm single voice coil subs.

img deleted

1 pair of terminals.. single voice coil.

That's not really helping. An explaination of what is good and bad and WHY would be more usefull.

[ShadowFX]

i was just saying, since he is always saying theyre DVC subs. two of these subs, then wired in parallel to the monoblock, would be perfect. This would then put out 456W RMS into the subs, leaving the amp plenty of headroom, since the subs only need 250W RMS (most daily listening will only be maybe 110-150W).

you cant use the 2 channel amp now, since the 2 channel is only 4 ohm stable in bridged mode. Also, to run subs, its always better to run them off a subwoofer dedicated monoblock amp, they are typically stable to lower impedances.

[RocketScott]

i was just saying, since he is always saying theyre DVC subs. two of these subs, then wired in parallel to the monoblock, would be perfect. This would then put out 456W RMS into the subs, leaving the amp plenty of headroom, since the subs only need 250W RMS (most daily listening will only be maybe 110-150W).

you cant use the 2 channel amp now, since the 2 channel is only 4 ohm stable in bridged mode. Also, to run subs, its always better to run them off a subwoofer dedicated monoblock amp, they are typically stable to lower impedances.

Your saying it backwards. In bridged mode the amp is only stable to 4ohms. Each channel is stable down to 2ohm which is to say that it can handle from 2ohms and up. Why would you run that amp in bridged mode anyway? He'll get cleaner sound if he uses one channel for each speaker. I did the same thing with my 8" subs in the door. Seperation isn't so important if these are going to be in the trunk but it is an option. All the amps mentioned have low pass filters and the lowest that any of them will go is 32Hz. That mono amps is nice but it is more than he needs and $200 more than he needs to spend. I can think of lots of things to spend $200 on. The real problem with the 2 channel amp is that it will only put out 97W RMS.

Your right about calling them DVC. Urbandork: those subs are SVC, stop calling them DVC.

SVC= single voice coil
DVC= dual voice coil

[ShadowFX]

Haha sorry, yeah, I wasnt thinking about running one sub off each channel, no idea why. Running off the 2 channel, he'd get only get 97W to each sub, which leads me to worry he'll more than likely push the amp into clipping (push the amp to its limits, sending high voltage spiked signals to the sub, ptentially damagaing them) . To run 250W subs, this is leaving the amp no headroom whatsoever.

[Consynx]

since the obvious was never stated
Ohm should be a measurement of resistance, the more resistance in a speaker the better the quality(or so i believe, not 100% on how speakers work)
Watt is just a Joule/second (energy per second) the greated the energy it can handle, the greater the outputs it can have.

[urbandork]

ok so if i want to use the infinity reffrence subs with dvc (crutchfeild has a buy one get one free) which infinity amp do i want to get and how should i wire it up

[Consynx]

i believe you can take ONE DVC 4 ohm and wire it to be a 2ohm load...
Paralleling it...4X4/(4+4)=2
you do that and you can use a 2-channel amp where each channel is capable of powering a sub @2ohms

[RocketScott]

ok so if i want to use the infinity reffrence subs with dvc (crutchfeild has a buy one get one free) which infinity amp do i want to get and how should i wire it up

Wait, did you change which subs you want or are you still calling them DVC when they're really SVC.

[mikew04]

since the obvious was never stated
Ohm should be a measurement of resistance, the more resistance in a speaker the better the quality(or so i believe, not 100% on how speakers work)

The ohms in relation to a speaker is actually called impedance, and that is used amplifier selection purposes. You dont want to run a 4ohm car speaker on an amp in your house that is only stable to 8ohms - you could fry the amp. The resistance in the coil on a speaker will change greatly depending on the frequency being played. Like up to hundreds of ohms of resistance or more IIRC. And speaker quality has nothing to do with speaker impedance. You may have it confused with ohm load on amps, as they tend provide cleaner power at a higher impedance at the sacrifice of power.

The only 'good and bad' with dual and single voice coil subs is wiring options. You decide which you want based on the amp you are getting, how many speakers you are running, and what kind of load you want on the amp. One is not better than the other providing you have all the voice coils hooked up.

We can't decide on an amp for you to get, there are too many options out there. Just an FYI, I have not heard about Infinity amps being anything special, you might want to look around so you can save some money. In other words, you can find a better amp for the money. If you are set on getting (2, two) 4ohm DVC's (the infinitys will be model number 1042w or 1242w, not 1040 or 1240) then find an amp that puts out 500w rms at 4ohms (either 500x1 or 250x2,) or find an amp that puts out 500w rms at 1ohm. Just know that you can spend less on the amp if you get 4ohm SVC's because you can run 2 at 2ohms.

And it's long, but everyone should read this.

[Hanyo]

so much info in this thread, i love it!

just to clarify:

1) you want an amp that is more powerfull then the subwoofer. Because when the amp is working at its 100% power it sends surges to the speaker, which will damage it.

2) The ohm level have nothing to do with sound quality. When you parellel subwoofers to obtain a lower over all ohms; You are essentially are trying to get more power from the amp at the risk of less "clean" power.

-----2q) what does clean power mean?

----- 2q) Does this mean its safer to use higher ohm speakers with a typical amp?

----- 2q) Does this mean an amp with a higher amp rating at a lower volt is better? For example: amp A:is 50 wats @ 8ohms..... Amp B: is 50 watts @ 4 ohms. In this example, amp B would be better because it can provide the same power at a lower ohm?

[ShadowFX]

If you use a higher impedance speaker with an amp, it will still run, but not as efficiently. Safer, is a bit iffy. Say, your running an 8ohm speaker to an amp thats maybe 50W at 4ohm. Running this with a load of 8ohm will produce 25W, and since it will be producing half the power, the user is more likely inclined to push the amp harder, into clipping, and possibly damagaing the speaker and/or the amp.

All things being the same, IF amp A is stable to 4 ohm, then amp A is better, since it would produce approx. 100W at 4ohm.. i think. This is assuming both amps are 4ohm stable.