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post #1 of 75 Old 04-09-2014, 04:37 PM - Thread Starter
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Ok, building began yesterday on this awesome speaker. As usual Erich did an amazing job with the packaging and components. I am really loving this build so far. I was going to do a build thread but of course I was anxious to start it and I know most of us have seen one of these centers, plus I am not bringing anything new to the table. I did speak to a local organ repair place and they suggested flat black paint to cover the purple of mid driver. He said it doesnt add anything as far as weight, he uses all the time. Hopefully it will turn out ok. Here are a couple of pics and as I progress I will put out more pics and description. I do need help with the crossover, so if anyone has worked on these before please see the second post. I am scratching my head on this one.





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post #2 of 75 Old 04-09-2014, 04:41 PM - Thread Starter
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Crossover, I can identify all the parts and which speaker they go to (mid/tweeter) the problem I am having is connecting them all together. Which order they go in and why the input should only have 2 wires but the diagram from DIY has 2 inputs (+- & +-) Any chance anyone has a picture of the bottom of their crossover. I searched the posts on here, DIY and PE and cant find one. I just need to know the order from input to output. I am on my way to Radio Shack to get some of the terminal connectors that go on the ends.


I would love to put these together tonight. Thank in advance for the help.
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post #3 of 75 Old 04-09-2014, 08:00 PM - Thread Starter
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I need some help. I've been trying the crossover for the 3 he's and nothing works. I end up getting a 4ohm load at the end of wiring everything in. I'm pretty sure it should be a 6ohm load. Here is my wiring. Any suggestions?


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post #4 of 75 Old 04-09-2014, 08:16 PM
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that looks correct to me, not sure why the load reads differently but it looks like its wired correctly
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post #5 of 75 Old 04-09-2014, 09:06 PM - Thread Starter
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post #6 of 75 Old 04-10-2014, 01:45 AM - Thread Starter
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I take that back, after putting everything together and tightened I am back to 4.1ohms. It must have been a fluke that I got that 6.7ohm reading. I am racking my brain and cant think of what it might be. I tested everything connected with my receiver and I get sound out of every speakers. Nice sound too, its hard to tell because its late and I cannot turn it up plus they are not in their box yet. The weird thing is that I tested the side withe tweeter only and I get no reading, I test the side with the mid woofers and I get the 4.1ohm reading. Its almost as if all the components on the tweeter side are doing nothing.

Any thoughts?
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post #7 of 75 Old 04-10-2014, 04:37 AM
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I would love to see a tutorial or something similar on how to properly read and decipher a crossover diagram, such as the ones included in these kits from DIYSG. Hopefully someone more knowledgeable than myself can post a step by step, easy to understand, diagram or tutorial regarding how to assemble these crossover components for these various Seos based speakers.
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post #8 of 75 Old 04-10-2014, 04:40 AM
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I thought it was easy assembling my crossover for the Tempest. I laid everything out exactly as it was shown in the schematic. From there I moved some of the components around to make it more compact but kept the same connections.

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post #9 of 75 Old 04-10-2014, 06:40 AM
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If you're using a standard multimeter measuring resistance, that's not necessarily going to tell you anything useful. Resistance and impedance are different things, and impedance varies with the signal going through the circuit. If it works when you plug it into the receiver, you're probably in good shape.
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post #10 of 75 Old 04-10-2014, 07:57 AM
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rhodesj:

That misconception comes up all the time cool.gif

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post #11 of 75 Old 04-10-2014, 09:05 AM
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Wow nice ! I'm jelly. My fusion 8s arrive Friday smile.gif

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post #12 of 75 Old 04-10-2014, 09:06 AM
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Quote:
Originally Posted by Martycool007 View Post

I would love to see a tutorial or something similar on how to properly read and decipher a crossover diagram, such as the ones included in these kits from DIYSG. Hopefully someone more knowledgeable than myself can post a step by step, easy to understand, diagram or tutorial regarding how to assemble these crossover components for these various Seos based speakers.

In for answer and advice myself smile.gif

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post #13 of 75 Old 04-10-2014, 09:29 AM
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Quote:
Originally Posted by Martycool007 View Post

I would love to see a tutorial ...
Is there money in that? biggrin.gif

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post #14 of 75 Old 04-10-2014, 10:07 AM - Thread Starter
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Quote:
Originally Posted by rhodesj View Post

If you're using a standard multimeter measuring resistance, that's not necessarily going to tell you anything useful. Resistance and impedance are different things, and impedance varies with the signal going through the circuit. If it works when you plug it into the receiver, you're probably in good shape.

Rhodes, thanks for the reply. My meter has an ohm selection and I tried it on my other speakers and it seems to be working fine. I get 6ohm readings for the other fronts and 3.9 ohms for my sub. I think my culprit is the little black one right at the begining of the tweeter network. It says 400volts on it and when I connect my meter to the ends of it nothing happens, even when switched to volts section. I tried all the other parts and they all indicate correctly. I don't know what else to do at this point. I am worried that if I connect the speaker to my system it will blow something, I think I am just going to close my eyes and order the pre-built crossover.
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post #15 of 75 Old 04-10-2014, 10:14 AM
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There is no continuity across a capacitor. This is normal.
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post #16 of 75 Old 04-10-2014, 10:16 AM
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Quote:
I think my culprit is the little black one right at the begining of the tweeter network. It says 400volts on it and when I connect my meter to the ends of it nothing happens, even when switched to volts section.
That's because you are reading a capacitor which charges and discharges:

http://www.electricaltechnology.org/2013/06/how-to-check-capacitor-with-digital.html

Some meters have cap settings

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post #17 of 75 Old 04-10-2014, 10:20 AM - Thread Starter
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Thank you both, that is one less thing to worry about. I know this is a stupid question but any chance that the speakers need to loosen up and that will raise my ohm reading? The reason I say this is because if I move the mid woofer up and down a little the ohm reading fluctuates. Could this be that case since I have them facing up all the weight is on pushing down and making the reading lower?
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post #18 of 75 Old 04-10-2014, 10:22 AM
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Quote:
if I move the mid woofer up and down a little the ohm reading fluctuates.
By flexing the cone you are inducing a voltage:
A speaker is a microphone in reverse and vs versa biggrin.gif

http://www.audio-technica.com/cms/site/b0d226992d31e25d/

"With a speaker, current from the amplifier flows through the coil. The magnetic field created by current flowing through the voice coil interacts with the magnetic field of the speaker's magnet, forcing the coil and its attached cone to move back and forth, producing sound output.

A dynamic microphone operates like a speaker "in reverse." The diaphragm is moved by changing sound pressure. This moves the coil, which causes current to flow as lines of flux from the magnet are cut. So, instead of putting electrical energy into the coil (as in a speaker) you get energy out of it. In fact, many intercom systems use small speakers with lightweight cones as both speaker and microphone, by simply switching the same transducer from one end of the amplifier to the other! A speaker doesn't make a great microphone, but it's good enough for that application. "

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post #19 of 75 Old 04-10-2014, 10:23 AM
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Nope. The reading should change while the speaker is shifting, but should be stable while the coil is still. Make sure the connections are solid at the woofer coil.

(We posted at the same time again. Hopefully it's clear that I'm not disagreeing with WVSyd, and we're saying the same thing. )
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post #20 of 75 Old 04-10-2014, 10:26 AM - Thread Starter
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Quote:
Originally Posted by WVSyd View Post

That's because you are reading a capacitor which charges and discharges:

http://www.electricaltechnology.org/2013/06/how-to-check-capacitor-with-digital.html

Some meters have cap settings

Thank you for this, my meter does have a cap reading and when connected to the cap it shows a quick 20something number then back down to OL. So the cap is good.
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post #21 of 75 Old 04-10-2014, 10:27 AM
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Were NOT disagreein'
smile.gif

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post #22 of 75 Old 04-10-2014, 10:27 AM - Thread Starter
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Quote:
Originally Posted by HopefulFred View Post

Nope. The reading should change while the speaker is shifting, but should be stable while the coil is still. Make sure the connections are solid at the woofer coil.

(We posted at the same time again. Hopefully it's clear that I'm not disagreeing with WVSyd, and we're saying the same thing. )

Thanks Fred, I used spade connecters and they all seem tight but when I put them in the box today I will make sure they are tighter.
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post #23 of 75 Old 04-10-2014, 10:34 AM
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Cessna,

 

I just discovered this thread for the first time today.......

 

LOOKING GOOD!  Im looking forward to seeing it completely finished, and hear your listening impressions.  

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post #24 of 75 Old 04-10-2014, 10:36 AM
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As Rhodes mentioned earlier:
The use of a meter depends upon the circuit.
Music alternates - it is in essence AC.
It doesn't mean that DC doesn't apply, just that the aspects of AC have to be considered:
it's the reactive nature with respect to frequency, phase and time etc.

One of the things one notices when measuring small signal T/S on woofer cones is how sensitive it is to the test conditions.
A device like WT2 will display a puff of breath on the cone.

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post #25 of 75 Old 04-11-2014, 05:28 AM
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Quote:
Originally Posted by WVSyd View Post

Is there money in that? biggrin.gif

I would definitely pay someone to give me a personalized tutoring for learning how to interpret & build crossovers based on various diagrams.

I would really be willing to pay a lot more to have someone do over the phone tutoring sessions to teach me how to build and design crossovers from the ground up. Seriously! I could see possibly talking via phone or Skype like 30 minutes to an hour every week for several months or however long it would take.

I absolutely love this hobby, and it is my dream to learn how to properly design and build crossovers and speakers. I do research on a daily basis and although some folks get annoyed with me, I tend to ask lots of questions on things that I don't understand.
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post #26 of 75 Old 04-11-2014, 11:01 AM
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Quote:
Originally Posted by Martycool007 View Post

I would definitely pay someone to give me a personalized tutoring for learning how to interpret & build crossovers based on various diagrams.

I would really be willing to pay a lot more to have someone do over the phone tutoring sessions to teach me how to build and design crossovers from the ground up. Seriously! I could see possibly talking via phone or Skype like 30 minutes to an hour every week for several months or however long it would take.

I absolutely love this hobby, and it is my dream to learn how to properly design and build crossovers and speakers. I do research on a daily basis and although some folks get annoyed with me, I tend to ask lots of questions on things that I don't understand.

Actually this might be cool. A group project or multiple skype call.
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post #27 of 75 Old 04-11-2014, 01:00 PM
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Fundamental material:
http://hyperphysics.phy-astr.gsu.edu/hbase/audio/cross.html#c1
http://hyperphysics.phy-astr.gsu.edu/hbase/audio/cross.html#c2

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post #28 of 75 Old 04-11-2014, 01:05 PM - Thread Starter
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post #29 of 75 Old 04-11-2014, 01:09 PM
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You are welcome. ( Mine that site )
( I'm posting some others Sound related stuff cool.gif )

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post #30 of 75 Old 04-17-2014, 01:25 PM - Thread Starter
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Ok looks like I am done for now. I am not loving the 5/8" roundover on the edges. Made the box too look too round. For now it stays like that. Starting this weekend I will be working on a different design with a thick veener, 1/4" round over and American Oak color to match the 80 year rocking chair I refurbished for my wife last christmas. I like the rich dark color.



Here is the finished product. On one of the pics you will see that put it on top of my Marty cube on the right. My plan is to use 3 of these across the front as the L/C/R. Does anyone see a problem with that? Can I move the waveguide to the top say and have the 2 8" mids together? How does that change the sound?





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