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Old 28th July 2010, 05:41 PM   #21
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Quote:
Originally Posted by AndrewT View Post
Be wary of using Left and Right into a dual VC driver. If the signals are not in phase the VC cooling will be reduced and you could burn out the driver.
The signals are either in phase, mono or summed to center in the frequencies that would normally be sent to a subwoofer.
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Originally Posted by cbj591 View Post
You can hook up the left side to one voice coil and the right side to the other. That was the initial intent behind the dual voice coil speaker design.
Of course you can. A million of these things out there. Never heard of one dying because of out of phase bass. Can only imagine what out of phase bass might do to your stylus.
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Originally Posted by David_Web View Post
Bass is not always in phase
See above. You guys are worrying about the wrong things.
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Old 28th July 2010, 06:08 PM   #22
Boscoe is offline Boscoe  United Kingdom
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Nice thanks for the help everyone.

Basically this is how I want the setup:

Right channel: Main amp with sub woofer out > Internal amplifier in the sub > low level crossover > rightside voice coil

Left channel: Main amp with sub woofer out > Internal amplifier in the sub > low level crossover > leftside voice coil

Quote:
You can hook up the left side to one voice coil and the right side to the other. That was the initial intent behind the dual voice coil speaker design.
I did assume this but due to this post: I thought otherwise!

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when you put a right and a left signal in the diferen vc's and the signal is is stereo (diferent per chanel) you will rip the woofer apart.
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Old 28th July 2010, 06:28 PM   #23
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Methinks you have put the XO's after the amp
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Old 28th July 2010, 06:30 PM   #24
Boscoe is offline Boscoe  United Kingdom
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Methinks you have put the XO's after the amp
Active, from what the other guy said; it doesn't have to be that accurate and passive is a lot easier than active
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Old 28th July 2010, 06:33 PM   #25
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Quote:
Originally Posted by Boscoe View Post
Nice thanks for the help everyone.

Basically this is how I want the setup:

Right channel: Main amp with sub woofer out > Internal amplifier in the sub > low level crossover > rightside voice coil

Left channel: Main amp with sub woofer out > Internal amplifier in the sub > low level crossover > leftside voice coil
Looks like you might have made a mistake here?

Crossovers for post-amplifier use for subwoofers are often big and expensive. Ones for before the amplifier are small, but you need the extra amplifier.
As soon as you start tweeking the crossover, the active design is immediately cheaper, as those components cost pennies, not pounds...

I think bass is mono to from 80Hz down on most CD recordings, though I have heard ones where the bass is panned to one side (this was when stereo was new and exciting). This wouldn't be a problem as one of the amplifiers would sit and do little while the other drivers the speaker.

Chris

PS - you're unlikely to cook the coils anyway. Most speakers are surprisingly resilient.
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Old 28th July 2010, 06:34 PM   #26
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I'm getting more confused. Seems real strange or maybe I don't understand.

Why two amps to drive one driver? Why not have the voice coils in series?

Why not electronic crossover ahead of the woofer "plate" amp? That's much better for a whole bunch of reasons.


Footnote: now that I've been thinking about it, it does seem a poor concept to have two voice coils tugging in slightly different directions on one former even if their sum is nominally the output you want and mostly correlated (and folks have been doing this for decades with no failures that I've read about... or that anybody has been able to detect by ear).
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Old 28th July 2010, 06:36 PM   #27
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Sorry, I thought you were using active. Of course passive will go after the amp. Doesn't the internal amp in the sub have an XO?
Virtually 99% of plate amps have variable XO's built in
Cheers.
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Old 28th July 2010, 06:40 PM   #28
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I strongly suggest you go active. I have the perfect project for you on my website, a sub-woofer controller
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Old 28th July 2010, 06:40 PM   #29
Boscoe is offline Boscoe  United Kingdom
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Okay then new schematic thing!

Right channel: Main amp with sub woofer out > active filter > Internal amplifier > left and right coil in parrallel (or just any old single coil driver)

Left channel: Main amp with sub woofer out > active filter ^^ now are combined
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Old 28th July 2010, 06:43 PM   #30
Boscoe is offline Boscoe  United Kingdom
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I strongly suggest you go active. I have the perfect project for you on my website, a sub-woofer controller
okay that helps what would I need at the INV, NOR and SEL connections?
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