Watkins woofer question

Northwinds

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#21
I will try after the games Lee. I put off cutting the cabs for now also until I am sure of what is getting done. The terminals are marked pos/neg with a red dot on the hot side of each. I will post a back shot of the speaker. Maybe one of guys can make the drawn on arrow lines numbered to show how to do it
 

Northwinds

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#22
Again, I apologize for the shitty pics, I have no photo editing software on this computer and can only resize through Imgur. You see one set of terminals with the blue tape? There is an identical set on the opposite side of the magnet



 

Zach C.

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#25
I have a set of the 12" ones from Quantum 5's and want to put them in my SM-120 cabs. I have to cut the inner diameter a little more so I will be doing that tomorrow. Question is how do I wire them in since I am not using a dual coil crossover? Could someone diagram how to jump the 2 sets of terminals so I am running straight through both coils? Also, which coil would I go through first and how would I identify which coil is which?

Thanks in advance
I'm a little late on this, but...

Swapping woofers as you propose really opens up a big can of worms. A properly designed, crossover takes into account a number of things, including, but not limited to: driver impedance, sensitivity, and the driver's natural response. These are the things we're most concerned with in your scenario.

Chances are that you have two 8r voice coils, in which case, you can get either 16, or 4r using them series or parallel. Unless you're just very lucky, you will not be able to hook up your DVC woofer to present an appropriate load for the "new" crossover. And, even you are lucky enough that this works out, you likely still won't get a very flat response, since what you are really concerned with it the impedance at the crossover point, since impedance varies with frequency. IOW, the 8r is the nominal, or average impedance. It will be lower at some frequencies and likely much higher at others.

Even if you are lucky enough that this matches, you are still left with a possible sensitivity mismatch- the woofer will be playing too soft or loud relative to the mids and tweeters requiring a change in the crossover.

And, even if you are lucky enough that sensitivity works out, the woofers will likely have differing natural rolloffs which will change the effect the crossover has on the woofer's response, which will in turn effect the way the woofer and mid sum.

And, even if all of this works out, you still have to worry about box loading, which will effect bass response, and power handling. Since it looks like this new box is larger, if they are both sealed cabinets, you can always fill the larger cabinets to give a smaller internal volume comparable to the old box.

In short, it's a total crapshoot, and not likely to give you the result you desire.

I'm not familiar with the crossover for the DVC woofer, but chances are that it is used to provide baffle step compensation, by using one VC only at lower frequencies relative to the other coil.
 

kevin

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#27
You can call them. Last time I was in Kingsport, they were still there. Their number is (423) 246-3701. At onetime, thy still had replcement speakers for their product.
WOW.... I never dreamed he was talking about a pair of WSC'S... Thats the first thing I thought of when I saw Wakkins but I figured some other brand... Not WSC's... Hard to believe they are still there.. Ive got a Infinity Sub sitting here that I bought there YEARS ago ! The son had about taken over last time I was there... I bet that was 25 years ago ! Northwinds !!!! If for some reason you need someone to walk in the store for you I'm an hour away and off every Wed... Be more than happy to help you if I can !!!
 

Northwinds

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#28
Update

Cut the Infinity cabs yesterday so the Watkin's fit nice. Just want to get this wiring deal right the first time but I plan to use an Onkyo receiver for the sacrificial lamb if I get something wrong LOL

From crossover to + post coil #1 then - from coil #1 to + coil #2 then the other line from the crossover goes to the - on coil #2 right? This is so I can run the Watkin's as a normal woofer. Not sure if it will end up at 8ohms since coil #1 is 2ohms and coil #2 is 4 ohms but it should be close enough. I will watch for any heating issues when these are done and being run by the WOPL

On a side note... I found an old blurb from Bill Watkins stating that the cones are coated with something called "aquaplaz" WTF is that stuff? They almost feel like some sort of clay compound

Anyway, this project is at a dead standstill until I hear from someone here that I have the series wiring right
 
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Skynyrd77

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#29
I'm a little late on this, but...

Swapping woofers as you propose really opens up a big can of worms. A properly designed, crossover takes into account a number of things, including, but not limited to: driver impedance, sensitivity, and the driver's natural response. These are the things we're most concerned with in your scenario.

Chances are that you have two 8r voice coils, in which case, you can get either 16, or 4r using them series or parallel. Unless you're just very lucky, you will not be able to hook up your DVC woofer to present an appropriate load for the "new" crossover. And, even you are lucky enough that this works out, you likely still won't get a very flat response, since what you are really concerned with it the impedance at the crossover point, since impedance varies with frequency. IOW, the 8r is the nominal, or average impedance. It will be lower at some frequencies and likely much higher at others.

Even if you are lucky enough that this matches, you are still left with a possible sensitivity mismatch- the woofer will be playing too soft or loud relative to the mids and tweeters requiring a change in the crossover.

And, even if you are lucky enough that sensitivity works out, the woofers will likely have differing natural rolloffs which will change the effect the crossover has on the woofer's response, which will in turn effect the way the woofer and mid sum.

And, even if all of this works out, you still have to worry about box loading, which will effect bass response, and power handling. Since it looks like this new box is larger, if they are both sealed cabinets, you can always fill the larger cabinets to give a smaller internal volume comparable to the old box.

In short, it's a total crapshoot, and not likely to give you the result you desire.

I'm not familiar with the crossover for the DVC woofer, but chances are that it is used to provide baffle step compensation, by using one VC only at lower frequencies relative to the other coil.
I think all this stuff is how my speaker upgrade turned into a grand lmfao
 

Northwinds

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#31
I'm a little late on this, but...

Swapping woofers as you propose really opens up a big can of worms. A properly designed, crossover takes into account a number of things, including, but not limited to: driver impedance, sensitivity, and the driver's natural response. These are the things we're most concerned with in your scenario.

Chances are that you have two 8r voice coils, in which case, you can get either 16, or 4r using them series or parallel. Unless you're just very lucky, you will not be able to hook up your DVC woofer to present an appropriate load for the "new" crossover. And, even you are lucky enough that this works out, you likely still won't get a very flat response, since what you are really concerned with it the impedance at the crossover point, since impedance varies with frequency. IOW, the 8r is the nominal, or average impedance. It will be lower at some frequencies and likely much higher at others.

Even if you are lucky enough that this matches, you are still left with a possible sensitivity mismatch- the woofer will be playing too soft or loud relative to the mids and tweeters requiring a change in the crossover.

And, even if you are lucky enough that sensitivity works out, the woofers will likely have differing natural rolloffs which will change the effect the crossover has on the woofer's response, which will in turn effect the way the woofer and mid sum.

And, even if all of this works out, you still have to worry about box loading, which will effect bass response, and power handling. Since it looks like this new box is larger, if they are both sealed cabinets, you can always fill the larger cabinets to give a smaller internal volume comparable to the old box.

In short, it's a total crapshoot, and not likely to give you the result you desire.

I'm not familiar with the crossover for the DVC woofer, but chances are that it is used to provide baffle step compensation, by using one VC only at lower frequencies relative to the other coil.

I spoke with Bill on the phone about this. He said it's just a woofer... run it as the dual or it can be run as a regular single coil in large Infinity cab that is designed specifically for a 12" driver. These were used in a ton of Infinity 3-way systems. I just have to use the SM crossover since it already is set up for a same size driver. The Watkins are an 88 efficiency IIRC, the SM-120s originals ran 89-91 efficiency so I think all that is a moot point as the WOPL has more then enough power to drive these. I might have to tune the port at most

 

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#32
Ok, got everything in and ran them with a Sony rack system sitting in the garage. They ate the 135w per channel up without burping. Brought them out and hooked them up to the WOPL

I can tell these are sucking up power like a mofo because the needles are swinging very quickly to the red zone at far lower preamp volume settings then the CV's. Should I be careful here Lee (about really laying the gas into them). Moderate volume now and the fins feel nice and cool. Highs seem abnormally rich, I have the treble down to full off and the crossover controls at the lowest setting. Not sure if I mean sharper detail maybe? Way more intense these Polycells then whatever is in the CV's. The bass is ridiculously tight

EDIT: Have this running with the needles flat at 0bds peaking to +3 for transients. Fins are barely warm? What's going on here? It's wicked loud in here, Debbie can't hear on the phone with the bedroom door closed all the way over on the otherside of the house. The bass is so tight but it's EVERYWHERE
 
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laatsch55

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#33
You're about 6.2 ohms so dips are going to be a lot lower somewhere in there. Monitor you heatsink temp and throw the room fan on if they get warm. Shouldn't hurt the amp. If it clips drop it down a bit. I can almost get a 400 to clip on the horns.
 

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#34
You're about 6.2 ohms so dips are going to be a lot lower somewhere in there. Monitor you heatsink temp and throw the room fan on if they get warm. Shouldn't hurt the amp. If it clips drop it down a bit. I can almost get a 400 to clip on the horns.

Will do. It's wierd Lee, I started really laying into it and it seemed instead of a loudness factor increase, it is more like a soundstage increase? Really wierd. Heatsinks are cooler then they would be with the CV's at the same volume position. I mean, we can converse pretty well right now 10-12' apart but it's like your enveloped in sound like being at an outdoor concert and your away from the PA. Just really wierd...
 

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Ok, got Frank Marino in playing Sister Change. Flattened the needles to the right and everything is crystal clear, amp is running cool and yet we can still converse, it does not seem loud here enough to warrant what the needles are indicating. It's like these speakers are not even breathing hard though I am pretty sure I am close to the protection limits on the tweeters and mids but they are singing clear also???? I am wondering if maybe I should reverse the crossover wires on the Watkin's??? Does it make a difference which coil is gone through first? It should not make a difference. I know the Watkin's have been shown to take 500w easy but this is ridiculous
 

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#37
Ok, got Frank Marino in playing Sister Change. Flattened the needles to the right and everything is crystal clear, amp is running cool and yet we can still converse, it does not seem loud here enough to warrant what the needles are indicating. It's like these speakers are not even breathing hard though I am pretty sure I am close to the protection limits on the tweeters and mids but they are singing clear also???? I am wondering if maybe I should reverse the crossover wires on the Watkin's??? Does it make a difference which coil is gone through first? It should not make a difference. I know the Watkin's have been shown to take 500w easy but this is ridiculous
That is a strange woofer with different impedance values for each of the 2 coils. Are you sure that one of the 2 coils is just not damaged?

Test the woofer using a fresh 1.5V D cell. Apply the battery + to the + of coil #1 and the battery - to the - of coil #1. Observe which direction the cone moves, in or out. Remember that.

Then do exactly the same for coil #2.

If the cone movement is the same for both of your tests then the polarity markings on the woofer hold up. If the cone movements are different then this is some strange woofer indeed (not sure what they were thinking).
 

Northwinds

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#38
Ok... sorry bros but...

I literally took the volume up to the level where the preamp would not increase volume so it's at max current output, the amp is barely warm and the speakers are playing crystal clear. Have I somehow managed to be able to run a WOPL to it's theoretical limits and it just won't clip because the impedence is a little lower then 8ohms? I am thinking right now these speakers as they sit right now will eat a 700B up no problem and still want more. I wish one of you guys was local to come over and see what I am talking about
 

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That is a strange woofer with different impedance values for each of the 2 coils. Are you sure that one of the 2 coils is just not damaged?

Test the woofer using a fresh 1.5V D cell. Apply the battery + to the + of coil #1 and the battery - to the - of coil #1. Observe which direction the cone moves, in or out. Remember that.

Then do exactly the same for coil #2.

If the cone movement is the same for both of your tests then the polarity markings on the woofer hold up. If the cone movements are different then this is some strange woofer indeed (not sure what they were thinking).
Joe, I ran both coils independently before running them series. They both run fine but I will try your test, have to get a battery. The positive sides of each coil are painted red. This is why I wondered if I should reverse them and see if one coil is out of phase in each speaker
 

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Ron, check what Joe suggests, that might shed some light on it. Are the voice coils heating up? If an increase in power does not reflect an increase in volume the extra power is being converted to heat somewhere..
 
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