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Re: two amps one sub, lets bebunk this myth!!

I think the more important question(s) to ask here is(are): What (or how much more) distortion would be the result of sending stereo/different signals to the coils on a DVC speaker, would it be audible to most people?

I'm trying to understand your thought process here.
At 80 Hz and down a large amount of people cannot hear 15% distortion - hence the "My sub took a shit and I was playing it very low"-POSTS

amp is sent into clipping 24/7 because they bought a really cheap ass amp and clipped it til hell wouldn't have it.

End result ?:p
 

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Re: two amps one sub, lets bebunk this myth!!

Yes it can be done! I've done this many times in Db Drag. Not recommended for daily driver. You have to match the voltage output of the amps. You can actually run 4 amps on one sub. 2 amps strapped on one voice coil and 2 amps strapped on the other. But I can't stress it enough the voltage output HAS to be matched! If one voice coil will end up frying and sounding like a spring or seizing up!!
 

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Re: two amps one sub, lets bebunk this myth!!

Yes it can be done! I've done this many times in Db Drag. Not recommended for daily driver. You have to match the voltage output of the amps. You can actually run 4 amps on one sub. 2 amps strapped on one voice coil and 2 amps strapped on the other. But I can't stress it enough the voltage output HAS to be matched! If one voice coil will end up frying and sounding like a spring or seizing up!!
But if both coils are wrapped TOGETHER how would you smoke one and not the other?
 

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Re: two amps one sub, lets bebunk this myth!!

But if both coils are wrapped TOGETHER how would you smoke one and not the other?
both coils are wound NEXT to each other but they are not wrapped together in the electrical sense. If you were an electron and could physically travel within the wire of a DVC where each coil was on a separate amplifier, and you started "walking" through one lead of coil #1, you would exit the other lead of coil#1---at no time would you be inside of coil #2's wire. They are physically separate.(series/parallel wiring is different---this thread isn't about that)

Another example is that if you took one lead from the outermost coil, and literally unwound it from the former, you could literally unwind that entire coil and have one super long length of straight wire, while the other coil (that was wound first) would still be there on the former completely intact.

That is how you can cause an open coil in one coil of a dual-voice-coil subwoofer if one coil is getting more power than the other. I'm not saying that it happens often, but it is possible.
 

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Worthy of consideration is the fact that when you strap amps their output resistance becomes seriesed so you lose a bit on damping factor. By all accounts unless you need to strap amps to achieve the correct ohm load one amp (gain matched from the same signal) per coil is preferred.

I've never heard of feeding a L and R signal into either coil. Seems to me like that might not be optimum
 

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Re: two amps one sub, lets bebunk this myth!!

Maybe I've missed something.
In your first couple posts you stated that you agreed with the link you posted.
It sound as though you're know unsure on your stance.

I assume you're referring to subs.
Is this really relevant with the cheap class D power available today?

From your last post: "how would this degrade the life of the speaker".
Unless the varnish/glue holding the coil windings fail and cause a short, what would cause degradation of the speaker?

I think the more important question(s) to ask here is(are): What (or how much more) distortion would be the result of sending stereo/different signals to the coils on a DVC speaker, would it be audible to most people?

I'm trying to understand your thought process here.
Yeah that was the first thing I thought of, little more than a couple hundred can get you a 2000 watt RMS 1 ohm stable monoblock. Still an interesting thread though, always am curious about things like this.
 

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nobody actually answered this question properly, haha...

or they forgot the reason DVC subs were first implemented? Maybe it's just my thinking cap is defective, but I remember when amps were not always bridgeable, and those were used to drive normal speakers but subwoofers were new, and the size of the motor and the cones, meant that more power was needed to run them correctly.

If all you had was basic 20W/ch power limited to 14V input, the use of two channels to a single voice coil former would effectively allow deeper bass extension and output than what was available at the time.

You had a couple of companies that could make 50W/ch at that time, early seventies, but not very many were bridging capable. This too, was a place for DVC subs.

Also, since it was understood that l+r meant that you had to combine both sides to get all the bass into the sub from the source material, you could use a single sub with left plus right input, by driving separate coils on the sub.

the idea that the bass could also cancel out, wasn't pushed so much since most bass at the time was mixed to mono for LP vinyl playback, because stereo bass in the grooves would lead to needle bounce and jump-out.

with CD introduction the source material changed and the need for a stereo bass configuration became more important, while the extra uses of DVC subs for lowering impedance to wring every last watt from the amps, became hot buzz.


then, the market actually produced variable Q subs, using extra coils and technology that made it easy to buy one sub and use it in sealed, ported, or IB configuration.

that should have gone over better, like the Infinity variable Q subs, but it didn't.

The Ascendant Audio Atlas was a well designed speaker hindered by a slightly too small vent in the pole piece. I think it would have done well if someone could have connected the Q coil to a switch that also operated a servo door, so that the sub could play sealed in a smaller enclosure, then open up to a vented alignment while the Q could also change, to a lower Q in the vented box.

then, the same sub that was "tight and clear" in a sealed config playing jazz quartet, would turn into a low bass monster using a port and correct Q tuning. For the rap special, or EDM...
 

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As long as the signals are in phase , dosent matter if it's stereo or not it won't matter. And the gains do not have to be matched . It will just play both signals through the movement of the cone. It's like two people carrying a heavy box . One might be stronger than the other they both carry it just fine. As long as one of the people aren't pushing down instead of lifting it will be fine

Could you imagine if someone said hey let's lift this sub box into my car and the person helping was pushing down so the other couldn't lift, I mean , it's a no brainier .

In fact I did it on my car had 2 hd1200/1 on a sundown sad2 15 sold one of the amps now I have one amp same sub . Sub works fine
 

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If you strap two or more amplifiers together, I think all that happens is that the audio is in-sync. between the two amplifiers. Those RCA cables don't carry a very high wattage load. Does this clarify the thread? Pretty sure at least.
 

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I’m trying to figure out if this setup would work properly:

Pioneer P99RS
2x JL XD1000/5v2 amps
1x Dual voice coil sub

I would have to run the Left rca from the P99 to the left sub input of one amp, and the Right rca to the right sub input of the other amp. Then one amp to each voice coil of the sub.
Would this work properly? My main concern is with the auto tune setup of the P99. My thoughts are the P99 would send slightly different signals to each amp and thus not hit the sub equally... thoughts? Suggestions??
 

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your idea will work except I'd run both rcas to the amp, then y split at the first amp and run to the 2nd amp. set gains very carefully, preferably all the way down then hit the sub out on the pioneer hard to get the output you need. higher voltage into the amps will be nice anyways.
 

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It can be done, it's not that hard. You can run two mono sub rca's, one to each amp (you can use a Y splitter on each cable if need be). Or if the amp has an output, you can run that to the second amp. I'd try to match the gains as close as possible.

OR sell the two amps and buy one BIG amp that will do what you are wanting. Would be easier to tune this way. Less wiring too.
 

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This is the proper way to ruin a sub woofer in a spectacular way. Even if you ran 2 amps to 1 sub, try to remember the timing of the cycles say at 40hz. Thats 40 cycles per second, Im going to try to make this easy. So if either amp or signal is delayed for any reason but a fraction of a fraction second you now have 2 motors fighting each other. This can maybe generate more heat, or just rip each other apart! Running two different frequencies would be epic.

I say ignore physics and do it, perhaps you will time travel if you have enough power.
 

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Re: two amps one sub, lets bebunk this myth!!

Yes it can be done! I've done this many times in Db Drag. Not recommended for daily driver. You have to match the voltage output of the amps. You can actually run 4 amps on one sub. 2 amps strapped on one voice coil and 2 amps strapped on the other. But I can't stress it enough the voltage output HAS to be matched! If one voice coil will end up frying and sounding like a spring or seizing up!!
What? How does that work then? If they are not matched they don’t die period!

I’ve used 5k amps strapped on one coil and 7k amps strapped on another coil... guess what nothing died!

The only way to kill a woofer is excess heat however it’s caused or mechanical failure coils are interwound so if one gets hot the other will also, sure one can pop before the other but that doesn’t mean they need to have identical voltages or signals even
 

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This is the proper way to ruin a sub woofer in a spectacular way. Even if you ran 2 amps to 1 sub, try to remember the timing of the cycles say at 40hz. Thats 40 cycles per second, Im going to try to make this easy. So if either amp or signal is delayed for any reason but a fraction of a fraction second you now have 2 motors fighting each other. This can maybe generate more heat, or just rip each other apart! Running two different frequencies would be epic.

I say ignore physics and do it, perhaps you will time travel if you have enough power.
The physics of it - is that electricity travels at the speed of light. There is no way it will be "slightly delayed for any reason". There is no reason.

The tweeter frequencies being well imaged at 5-20kHz proves that, and at 40 it is be easier to be perfect... which it already was at 20kHz.


The idea of running two separate frequencies on two separate coils, ignores how the motor works in a quiet profoundly
 
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