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

Nothing on that page talks about running two separate amps to one sub.
 

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

Nothing on that page talks about running two separate amps to one sub.

LMAO. none at all.

Here's Two girls one cup, err, i mean two amps, one sub in a nutshell. They must be strapped if possible ending up as one amp anyway, or you feed two amps to two coils on the same sub (one amp per coil).
the amps must be the same and it very beneficial to gain match the amps to be sure each coil is getting the same power and the same mono signal as to not try to feed a stereo signal to one speaker. Thats it....no myth.
 

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

That's debunk by the way. ;)
 

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Discussion Starter #5
Re: two amps one sub, lets bebunk this myth!!

@ jking29
my bad, should have been more specific, two separate signals to one sub, which could be substituted as also one signal from one amp and one signal from another amp. meaning, as it said in that pdf file:

There's one thing that often comes up about wiring DVC subs, and that is the mistaken conclusion that
running different signals to each voice coil will "ruin" the driver. Let's recall how a dual voice coil driver is
built. Basically, a dual voice coil driver consists of two motors (the voice coils) co-axially mounted (that is,
wound together on the former) to a single diaphragm. The net force on the diaphragm is the sum of the
inputs of the two motors.

So, when we run two different signals to the voice coils, what we find is that the magnetic fields of the two
combine to generate a net TOTAL field that interacts with the static field of the magnets. The two voice
coils NEVER fight each other in a physical way; it's all in the magnetic field.

@brownmoses
as you said, one amp per coil, and matched. I've spent the past year on these forums and the net in general, and its pretty widely accepted that if you feed anything other than a mono signal to amy speaker it will magically eat its self up. all im trying to do is make people understand why it wont. people come to these forums for advice and direction, and it seems most times a good post goes bad because people run off on tangents or start to bicker and take shots at eachother.
just trying to get some info out there to the "less informed"
 

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

So, when we run two different signals to the voice coils, what we find is that the magnetic fields of the two
combine to generate a net TOTAL field that interacts with the static field of the magnets. The two voice
coils NEVER fight each other in a physical way; it's all in the magnetic field.
Can I run 80 Hz to 120 Hz to one voice coil from one amp and run 75Hz and down form another amp to the second voice coil ?
 

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

sure you CAN ... may not do much for you
 

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

@ jking29
my bad, should have been more specific, two separate signals to one sub, which could be substituted as also one signal from one amp and one signal from another amp.

There's one thing that often comes up about wiring DVC subs, and that is the mistaken conclusion that
running different signals to each voice coil will "ruin" the driver. Let's recall how a dual voice coil driver is
built. Basically, a dual voice coil driver consists of two motors (the voice coils) co-axially mounted
sure you CAN ... may not do much for you
Thanks PaulD,

Yeah my coaxials play from about 120 Hz and up 5.25's , just wanted to make sure my sub could due the co-axial thing too , for the remaining frequencies :cool:
 

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

Can I run 80 Hz to 120 Hz to one voice coil from one amp and run 75Hz and down form another amp to the second voice coil ?
I would say you can do anything you want, because as your mom used to say, "your special", might be short bus special, but none the less you are special!!!
 

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

If pitchblackcls6 says it's OK ... then i know I am G-O-L-D-E-N !
 

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

As I understand it, the reason DVC subs came about is because of the lack of powerful amps available at the time. So you would hook both channels of one amp to it, not necessarily a mono signal. The coils may not be working together optimally, but it shouldn't harm the woofer.
In other words I disagree that the amps "must" be gain matched perfectly or a mono signal "has" to be used or the amps must be strapped.
If you hook two identical amps to a dvc sub and the gains aren't "matched" you would not damage the sub, both coils would still contribute to the movement of the cone, just not equally.

Edit: I reread post #5 and agree with pitchblackcls6, the woofer will not be harmed.
 

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

JL Audio - Car Audio Systems


What is a dual voice coil speaker?
-
JL Audio Car Audio Systems

Where a dual voice coil subwoofer has an advantage is in giving the user greater wiring flexibility while avoiding speaker-to-speaker series connections
 

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

What happens when you run different signals into each voice coil of a dual voice coil speaker?
Essentially, if there is any difference between the signals driving each coil at any given point in time at a given frequency, the voice coils will either fight each other or help each other, depending on the phase relationship of the two signals at that frequency. This is not the same thing as bridging an amplifier and can create undesirable non-linearities and distortion because different input signals at each voice coil create shifts in the speakers electrical parameters.

For this reason, it is advisable to mono-bridge the amplifier whenever possible and connect the voice coils of the dual voice coil speaker together in parallel or series. If a dual voice coil subwoofer must be wired to two independent channels, the inputs to both channels should ideally be the same (summed mono) and every effort should be made to match the gains of both channels as closely as possible.
Hmmm
 

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

I don't see anything that states damage will occur, only that it's not optimal.
My thoughts on what you posted.
 

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

I don't see anything that states damage will occur, only that it's not optimal.
My thoughts on what you posted.
But . . . do U want to find out , that towing a boat with a 4 cylinder car can be done - once or twice before you need a new transmission ?

I mean if U do . then GO FOR IT !
 

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

so it seems that few people actually read that article, some looked at it but didnt read it.
has anyone actually tried this? im curious to see what the difference would be. how it would actually degrade the life of the speaker.

@oliver- yes you are golden because i said so, thanks for the shout out!
 

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

But . . . do U want to find out , that towing a boat with a 4 cylinder car can be done - once or twice before you need a new transmission ?

I mean if U do . then GO FOR IT !
It's interesting to me that you used an analogy that's directly related to a components ability to dissipate heat. The engine that's in front of the transmission is only one variable, a small one at that, that will dictate the life span of the transmission. In fact an eight cylinder with more available torque and a heavy foot will overheat the transmission faster than the four cylinder would. I could go on, but that's not what this topic is about.

I've learned not to concede to other peoples "opinions" if I have a decent grasp of the subject, it may cost me some of the time, but in most cases it turns out ok.

Unless you're approaching the thermal limits of the coil and it's ability to cool itself, no damage will occur. Either the two coils will contribute to motion or one will hinder the other.
 

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

cobra93,

Is it worth the price of an amplifier and subwoofer to try it ? ;)

I've seen guys try to use one coil on a DVC sub [ 3 dB less output when you use half the available motor, wrong box as parameters change ], can it be done ... sure !

would you want too ?

:D
 

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

so it seems that few people actually read that article, some looked at it but didnt read it.
has anyone actually tried this? im curious to see what the difference would be. how it would actually degrade the life of the speaker.

@oliver- yes you are golden because i said so, thanks for the shout out!
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.
 

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

cobra93,

Is it worth the price of an amplifier and subwoofer to try it ? ;)

I've seen guys try to use one coil on a DVC sub [ 3 dB less output when you use half the available motor, wrong box as parameters change ], can it be done ... sure !

would you want too ?

:D
How would this cause damage to the amplifier?
Using one coil most certainly changes the T/S parameters, but that's a different subject all together.

I've never seen a sub that only works under one set of enclosure parameters. Have you?
Couple that with the fact that everybody has their own preference as to what sounds good to them and the possible box parameters/wiring configurations are endless.
Would I use only one coil on a DVC sub, if it models/sounds the way I want it to, yes.

Did you read the link in post #1 in regards to using a variable potentiometer on one coil to change the Q of a woofer?
Why would this be suggested/implemented if damage to the woofer would result? This is from a manufacturer of subwoofers and some very good sounding subs, at least that's what I've read.

I don't propose this to be fact, just what makes sense to me based on my knowledge and understanding.
 
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