Thinking about running a single 8" sub powered by ~150W RMS. Suggestions?

[phenryiv1 10+ year member]

Uhh what?

I am not sure what you were trying to say in replying to my post, but...

A single DVC 4 ohm sub can be wired to 2 ohms or 8 ohms.

Yes.

Most amps bridged put out their power at 4 ohms.

Also affirmative. But if my amp is bridged and going to an 8 ohm load (the amp is operating at 4 ohms) I am only getting the 4ohm rated power out of it- not the 2ohm power (which would be 1.5-2x the 4ohm power). Thus, I am not optimizing my amp's potential if it is operating at 4 ohms.

(It can't safely operate at 1 ohm, so no need to discuss that.)

You need either a SVC 4 ohm sub or a DVC 2 ohm sub for a final 4 ohm load.

True...hence why I want either a 2ohm DVC or 4ohm SVC driver...

 

[IonRL205 10+ year member]

With me bridging 2 channels, the 4 ohm DVC configuration leaves me at 1 orm or 4. Amp can't handle 1 and won't be maximized at 4.

A 4 ohm DVC will not give you a 4 ohm load or a 1 ohm load, it's either 2 or 8. I don't know where you're getting this 4 ohm dual sub leaving you at a 1 or 4 ohm load...

Also affirmative. But if my amp is bridged and going to an 8 ohm load (the amp is operating at 4 ohms) I am only getting the 4ohm rated power out of it- not the 2ohm power (which would be 1.5-2x the 4ohm power). Thus, I am not optimizing my amp's potential if it is operating at 4 ohms.
(It can't safely operate at 1 ohm, so no need to discuss that.)

What are you talking about? Why would you bridge it to 8 ohms? You would want it at 4, where it puts out the most power bridged. And chances are your amp is not stable at 2 ohms bridged so I don't even know why are talking about getting the 2 ohm power?

I'm guessing your amp is 50w x 4 @ 4 ohm, 100w x 4 @ 2 ohm, or 200 watt x 2 @ 4 ohm bridged. Meaning if you bridged 2 of the channels, you would see 200 watts @ 4ohms, which is what you want. What's the model # of the amp?

 

[infamous_e46 5,000+ posts]

i have an old school pioneer premier 8 that is single 4ohm and is a sealed only sq sub

requires a tiny box

the sub is ugly but works well

45 shipped

 

[phenryiv1 10+ year member]

I kind of (note that I did not say that I DO) feel like a d!ck for talking like this in a thread where I am seking for advice, but this is the third post where I really have to wonder if reading comprehension is affected by inhaling too much MDF dust.

FROM THE BEGINNING:

I have a 4 channel amp. It is designed for 50 watts per channel and has 4 channels. Those channels can be bridged. See, I already posted this info...

I am considering a small enclosure (less than 0.4 cubes, if possible) with a single 8" sub that can be run by a 50x4 amp with 2 channels bridged to the sub. Front channels will power a set of CSX 265 components.

Remedial lesson: If I brigde 2 channels into 1 channel, the amp is running at HALF of the impedence of each channel individually. Thus, with a 4 ohm load, the amp will be running at 2 ohms. If I had a 2 ohm load, the amp would be running at 1 ohm. If I have an 8 ohm load, the amp is running at 4 ohms.

I thought that people here already understood this...maybe I was wrong.

On the the driver...

Two 2 ohm VCs in parallel are a 1 ohm load. Two 2 ohm VCs in series are a 4 ohm load. I WANT A 4 OHM LOAD WHEN I BRIDGE MY 3/4 CHANNELS ON THE AMP.

Two 4 ohm VCs in parallel are a 2 ohm load. Two 4 ohm VCs in series are an 8 ohm load. The 2 ohm load combined with bridging the amp will result in the amp running at 1 ohm. I DON'T WANT THIS because it will cook my amp. The 8 ohm load combined with my bridged amp will result in my amp running at 4 ohms. I DON'T WANT THIS because it is not optimizing my amp's capabilities.

A 4 ohm DVC will not give you a 4 ohm load or a 1 ohm load, it's either 2 or 8. I don't know where you're getting this 4 ohm dual sub leaving you at a 1 or 4 ohm load...

Where did I say this? I said that the amp would be operating at 1 ohm or 4 ohms- I never said that the LOAD would be 1 or 4 ohms.

What are you talking about? Why would you bridge it to 8 ohms?

Where did I say this? I stated that if I run two 4 ohm VCs in series that I woudl have an 8 ohm load, and that when bridged to that 8 ohm load, my amp would operate at 4 ohms.

You would want it at 4, where it puts out the most power bridged. And chances are your amp is not stable at 2 ohms bridged so I don't even know why are talking about getting the 2 ohm power?

I already said that the amp cannot run at 1 ohm (which results from 2 channels being bridged into a 2 ohm load). You called it 2 ohms bridged, but it is saying the same thing. My only mention of it is that the amp CANNOT run safely while bridged into a 2 ohm load...in other words, the amp can't run at 1 ohm.

You would want it at 4, where it puts out the most power bridged.
I'm guessing your amp is 50w x 4 @ 4 ohm, 100w x 4 @ 2 ohm, or 200 watt x 2 @ 4 ohm bridged. Meaning if you bridged 2 of the channels, you would see 200 watts @ 4ohms, which is what you want. What's the model # of the amp?

I DID say this...several times.

Amp is a Boston Accoustics GTA-504...

 

[whitedragon551 5,000+ posts]

Id look at the ID8's as well. I had a pair and loved every bit of them. Perhaps the box was off. Then again I was throwing about 350wrms on a single 8" that was rated for 150wrms-200wrms. You can check into the Dayton 8HF or the Tang Band 8" subs.

 

[trumpet 5,000+ posts]

I think what you're assuming is that bridging 2 channels cuts the sub system's impedance in half. This is not what happens. The amplifier does nothing to change the impedance of your subs. If you wire your subs to 4 ohms total on your bridged amp then your amp runs at 4 ohms, not 2 ohms.

 

[IonRL205 10+ year member]

I kind of (note that I did not say that I DO) feel like a d!ck for talking like this in a thread where I am seking for advice, but this is the third post where I really have to wonder if reading comprehension is affected by inhaling too much MDF dust.
FROM THE BEGINNING:

I have a 4 channel amp. It is designed for 50 watts per channel and has 4 channels. Those channels can be bridged. See, I already posted this info...

Remedial lesson: If I brigde 2 channels into 1 channel, the amp is running at HALF of the impedence of each channel individually. Thus, with a 4 ohm load, the amp will be running at 2 ohms. If I had a 2 ohm load, the amp would be running at 1 ohm. If I have an 8 ohm load, the amp is running at 4 ohms.

I thought that people here already understood this...maybe I was wrong.

On the the driver...

Two 2 ohm VCs in parallel are a 1 ohm load. Two 2 ohm VCs in series are a 4 ohm load. I WANT A 4 OHM LOAD WHEN I BRIDGE MY 3/4 CHANNELS ON THE AMP.

Two 4 ohm VCs in parallel are a 2 ohm load. Two 4 ohm VCs in series are an 8 ohm load. The 2 ohm load combined with bridging the amp will result in the amp running at 1 ohm. I DON'T WANT THIS because it will cook my amp. The 8 ohm load combined with my bridged amp will result in my amp running at 4 ohms. I DON'T WANT THIS because it is not optimizing my amp's capabilities.

Where did I say this? I said that the amp would be operating at 1 ohm or 4 ohms- I never said that the LOAD would be 1 or 4 ohms.

Where did I say this? I stated that if I run two 4 ohm VCs in series that I woudl have an 8 ohm load, and that when bridged to that 8 ohm load, my amp would operate at 4 ohms.

I already said that the amp cannot run at 1 ohm (which results from 2 channels being bridged into a 2 ohm load). You called it 2 ohms bridged, but it is saying the same thing. My only mention of it is that the amp CANNOT run safely while bridged into a 2 ohm load...in other words, the amp can't run at 1 ohm.

I DID say this...several times.

Amp is a Boston Accoustics GTA-504...

Please tell me how putting a 4 ohm load on your amp makes it run at 2 ohms. If you bridge to 4 ohms, your amp sees 4 ohms, NOT 2. Your sub is wired to 4 ohms, how does your amp just magically turn it into 2? It doesn't.

AND YES YOU DO WANT IT AT 4 ohms. You're trying to bridge it correct? Your amp does it's maxed power bridged correct? Your amp is bridgeable at 4 ohms correct? Now tell me why you DON'T want a 4 ohm load.

You honestly have no idea what you're talking about. Whatever load you put on your amp is what it sees, it doesn't get halfed/double, nothing. What it's wired to, is what the amp gets. (minus box rise and whatnot)

Maybe you should do some reading before you call people retarded. All I've been doing is trying to help you because you seem to be misinformed, but don't go around calling me retarded when it is indeed you in the wrong.

I looked up your amp, it says:

Bridged, 4 ohms: 160 watts x 2 chan, which means, 2 of your channels have now become 1 channel and do the power at the ohm load that's stated.

If you wired your sub to 4 ohms, and bridged it to channel 3/4, your amp would see a 4 ohm load and put out the 160 watts to your sub, which is what you want.

 

[phenryiv1 10+ year member]

I think what you're assuming is that bridging 2 channels cuts the sub system's impedance in half. This is not what happens. The amplifier does nothing to change the impedance of your subs.

I never said ANYTHING about the AMP changing the impedence of the subwoofers.

If you wire your subs to 4 ohms total on your bridged amp then your amp runs at 4 ohms, not 2 ohms.

That part is technically correct, but the equivalent load (in ohms) per channel is 2 ohms.

From here: Series Parallel Speaker Impedance

Go about 1/3 of the way down and enter "4" for the value of each VC and click on "calculate" to see the equivalent load.

 

[phenryiv1 10+ year member]

Please tell me how putting a 4 ohm load on your amp makes it run at 2 ohms. If you bridge to 4 ohms, your amp sees 4 ohms, NOT 2. Your sub is wired to 4 ohms, how does your amp just magically turn it into 2? It doesn't.

If the amp is bridged into a 4 ohm load, the equivalent load per channel is 2 ohms. I really don't know what else to say...It isn't magic- it is science. I don't pretend to understand all of the science, but I am able to read it and apply the simple math to get where I want to go.

You honestly have no idea what you're talking about. Whatever load you put on your amp is what it sees, it doesn't get halfed/double, nothing. What it's wired to, is what the amp gets. (minus box rise and whatnot)

Maybe you should do some reading before you call people retarded. All I've been doing is trying to help you because you seem to be misinformed, but don't go around calling me retarded when it is indeed you in the wrong.

I never called you retarded. I also fail to see where I have been misinformed. From the beginning, I have stated that in order to get the most out of my amp without cooking it, I want a single 8" woofer that is or that can act as a 4 ohm driver, whether that be a single 4 ohm SVC driver or a single 2 ohm DVC driver...I don't see where I have varied from this goal.

AND YES YOU DO WANT IT AT 4 ohms. You're trying to bridge it correct? Your amp does it's maxed power bridged correct? Your amp is bridgeable at 4 ohms correct? Now tell me why you DON'T want a 4 ohm load.

Again, I have ALWAYS stated that I wanted a 4 ohm load. Please, PLEASE tell me where I have stated ANYTHING other than that goal.

I looked up your amp, it says:
Bridged, 4 ohms: 160 watts x 2 chan, which means, 2 of your channels have now become 1 channel and do the power at the ohm load that's stated.

If you wired your sub to 4 ohms, and bridged it to channel 3/4, your amp would see a 4 ohm load and put out the 160 watts to your sub, which is what you want.

The 4 ohm brigded load is still an equivalent load of 2 ohms per channel...which is what I have been saying all along.

 

[IonRL205 10+ year member]

Ok dude, tell me wtf all this means then"

"With me bridging 2 channels, the 4 ohm DVC configuration leaves me at 1 orm or 4. Amp can't handle 1 and won't be maximized at 4.

The amp won't be maximized at 4 ohms bridged?. Yes it ******* will. You want the amp to be at 4 ohms so you get the 160 watts from bridging it. You can't bridge it at 1 or 2 ohms cause it won't handle it. You can't bridge it at 8 ohms cause you won't get the max power. What does that leave you with?

And actually that statement is completely wrong, because the only wiring options you have with a single DVC 4 ohm sub is 2 ohms and 8 ohm. Where you got 1 ohm or 4 ohms, i have no idea.

"I am looking for a 4 ohm load so that the amp "sees" 2 ohms (once bridged)."

Yes you want a 4 ohm load, but your amp doesn't turn it or see it as a 2 ohm load. However you wire your sub is how the amp sees it. It doesn't just magically change. Wiring your subs to 4 ohms will still be at 4 ohms when you bridge it. IT DOES NOT SEE 2 OHMS.

"But if my amp is bridged and going to an 8 ohm load (the amp is operating at 4 ohms) I am only getting the 4ohm rated power out of it- not the 2ohm power (which would be 1.5-2x the 4ohm power). Thus, I am not optimizing my amp's potential if it is operating at 4 ohms."

Everything about this is completely WRONG. If you wired your subs to 8 ohms and bridged them to the amp, your amp still sees 8 ohms. IT IS NOT OPERATING AT 4 OHMS, IT IS DOING IT'S POWER AT 8 OHMS BRIDGED. There is no 2 ohm power out of it unless you wire your sub to 2 ohms and connect it to one of the channels. That is the ONLY way your amp will safely see a 2 ohm load. Of course you could bridge it to 2 ohms, but your amp will go into protect. And yes you are using your amps potential at 4 ohms when you bridge your amp. No you won't see the full potential at 4 ohms on one channel, but when you bridge both channels you do.

"Remedial lesson: If I brigde 2 channels into 1 channel, the amp is running at HALF of the impedence of each channel individually. Thus, with a 4 ohm load, the amp will be running at 2 ohms. If I had a 2 ohm load, the amp would be running at 1 ohm. If I have an 8 ohm load, the amp is running at 4 ohms."

This is where you called me retarded. If you bridge 2 channels into 1 channel, your amp will still see the same ******* load. If you wired your sub to 4 ohm and stuck it on 1 channel, your amp will see 4 ohms. If you wired your sub to 4 ohm and bridged it with 2 channels, your amp will still see 4 ohms. The amp WILL NOT be running at 2 ohms UNLESS you wire your sub to 2 ohms. The impedance your amp sees DOES NOT CHANGE unless you wire your sub differently.

"Two 4 ohm VCs in parallel are a 2 ohm load. Two 4 ohm VCs in series are an 8 ohm load. The 2 ohm load combined with bridging the amp will result in the amp running at 1 ohm. I DON'T WANT THIS because it will cook my amp. The 8 ohm load combined with my bridged amp will result in my amp running at 4 ohms. I DON'T WANT THIS because it is not optimizing my amp's capabilities"

Why the **** do you keep saying this same bullshit? YOUR AMP DOES NOTHING TO THE LOAD WHEN YOU BRIDGE IT. YOUR AMP DOES NOT CHANGE THE IMPEDANCE EVER. HOWEVER YOU WIRE IT IS WHAT YOUR AMP SEES, PERIOD. It doesn't just go from 4 ohms to 2 ohms when you bridge it. It stays at 4 ohms. How hard is that to ******* figure out?

"Where did I say this? I said that the amp would be operating at 1 ohm or 4 ohms- I never said that the LOAD would be 1 or 4 ohms."

Are you seriously that ******* retarded? The load you put on your amp is what your amp operates at. If i wired my subs to 1 ohm and connected it to my amp, my amp would see a 1 ohm load and do it's power at 1 ohms. The same goes for you. If you wired your sub to 4 ohms and connected it to the amp, your amp would see a 4 ohm load and that's it. When you bridge the amp it becomes 1 channel and does the power at the load it says it does.

"Where did I say this? I stated that if I run two 4 ohm VCs in series that I woudl have an 8 ohm load, and that when bridged to that 8 ohm load, my amp would operate at 4 ohms."

Once again you say this same stupid bullshit. If you took your subs wired to 8 ohms and bridged it to the amp, it stays at 8 ohms, IT DOES NOT OPERATE AT 4 OHMS, IT OPERATES AT 8 OHMS, BECAUSE THATS HOW YOU HAVE IT WIRED. IF YOU WANT YOUR AMP TO OPERATE AT 4 OHMS, WIRE YOUR SUB TO 4 OHMS. BRIDGING IT DOES NOT CHANGE THE IMPEDANCE THE AMP SEES. HOW MANY TIMES DO I NEED TO SAY THIS?

"The 4 ohm brigded load is still an equivalent load of 2 ohms per channel...which is what I have been saying all along."

You may have been trying to say that, but nothing in ANYTHING you have said even comes to close to this. Either that or you know you're wrong and trying to change up what you've been saying.

 

[Epic0318 10+ year member]

i think the op thinks hes god and can wire any sub to any amp at any impedence he wants. lol.

wiring options:

SVC 4 ohm sub = 4 ohms

SVC 2 ohm sub = 2 ohms

DVC 4 ohm sub = 2 ohms or 8 ohms

DVC 2 ohm sub = 1 ohm or 4 ohms

study and memorize it and maybe one day you can wire your own subs. lol

 

[phenryiv1 10+ year member]

Dude, gtfo. Just gtfo. I made it perfectly clear that i knew what vc configuration(s) i wanted. If you want to come in here to try to make it sound like i don't know what i was asking for, just exit the thread. I want either a 4 ohm svc or a 2 ohm dvc. Either of those gives me the impedence that i want to run my am in a bridged configuration that will result in the amp driving the speaker with the 160w that it produces when in what you seem so hell-bent on referring to as 4 ohm bridged. Or what i correctly called bridged with each of the bridged channels seeing an equivalent load of 2 ohms.

I never, ever varied from what i wanted, and the only reason that any impedence discussion came up was when i said that a 4 ohm dvc setup was not correct for my needs.

Regardless of whether i used the scientifically correct terms, i was clear that i knew what i wanted and why. If you did not read that, well, we are back to the mdf inhallation issue...

 

[phenryiv1 10+ year member]

i think the op thinks hes god and can wire any sub to any amp at any impedence he wants. lol. wiring options:

SVC 4 ohm sub = 4 ohms

SVC 2 ohm sub = 2 ohms

DVC 4 ohm sub = 2 ohms or 8 ohms

DVC 2 ohm sub = 1 ohm or 4 ohms

study and memorize it and maybe one day you can wire your own subs. lol

Read up a few posts and you'll see that i posted that same basic chart. Thanks for the copy of what i already said.

I have been wiring 1, 2, and 4 driver setups with svc and dvc subs that were 4 or 8 ohm drivers since you were in kindergarden. I am yet to blow, fry, or shut down an amp due to not wiring up the proper load.

As i said- i know the configuration that i need, whether or not i properly explained the science.

 

[IonRL205 10+ year member]

Dude, gtfo. Just gtfo. I made it perfectly clear that i knew what vc configuration(s) i wanted. If you want to come in here to try to make it sound like i don't know what i was asking for, just exit the thread. I want either a 4 ohm svc or a 2 ohm dvc. Either of those gives me the impedence that i want to run my am in a bridged configuration that will result in the amp driving the speaker with the 160w that it produces when in what you seem so hell-bent on referring to as 4 ohm bridged. Or what i correctly called bridged with each of the bridged channels seeing an equivalent load of 2 ohms.
I never, ever varied from what i wanted, and the only reason that any impedence discussion came up was when i said that a 4 ohm dvc setup was not correct for my needs.

Regardless of whether i used the scientifically correct terms, i was clear that i knew what i wanted and why. If you did not read that, well, we are back to the mdf inhallation issue...

Sorry bud, but none of your posts come anywhere close to saying that. You wrote them all completely wrong and made yourself look like the retard. Don't put this **** on me when I corrected EVERYTHING you wrote because you don't know wtf you're talking about. Maybe it's you that needs to stop inhaling MDF dust...

And if you don't know the correct terms, don't make it seem like you do, cause that just makes you look like a *******.

 

[T3mpest 10+ year member]

A bridged 4 ohm load is just as hard on an amp as a regular 2 ohm load. Yes, it's still a 4ohm load, but in terms how the amplifier handles it, it's VERY similar. A bridged 4 ohm mono load is just like a stereo 2 ohm load. Bridging an amp simply uses each channel, one as the positive and one as the negative. Normally an amp uses each channel, with each channel swinging between a given amount of volts. Channel 1 can go from +5 to -5 for example.. (not negative voltage the current just flows the other way lol) Channel 2 would do the same.

A bridged amp uses each channel to simply drive one direction... So one side is +10 and the other is -10, which is why you only need to hookup one set of outputs when you bridge an amplifier.. Your still using all available potential voltage difference from the amp, so to not overload the amp you need to drive it against a higher impedence load.... Potential difference on each side of the amp his now doubly high, the load presented by the woofer needs to double or else your amp is going to go poof, resistance will be too low.... However, it'll put out the same amount of power it would have in 2 channels, now in one so it's all good. That's why amps that are bridgeable at a given load can also do a stereo load at 1/2 the impedence and 1/2 the power in each side.

If 2 ohms is simply 2 ohms then go ahead and bridge an amp that is stable at a given load in stereo at the same impedence bridged.. It'll heat up and fail very quickly, just as if your asking it to play at 1/2 the impedence it's supposed to be stable at.. Because in terms of voltage swings and potential difference that's exactly what your doing...