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Old 10th September 2013, 01:36 PM   #31
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Pabesco,

I will be building four of these as well. I read in some threads that people made them deeper to accomodate a different driver. I realy dont think heat will be an issue. If it was me I would always add an internal passive crossover. I bought 4 of these off ebay and think they will work quite well but I haven't started my build yet (330905586644 ebay item no.). Please post pics of build.

Thanks, John
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Old 10th September 2013, 02:54 PM   #32
Pabesco is offline Pabesco  Bahamas
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hi thanks for the reply and the info. i checked the crossovers on ebay and just had one question. the crossover are rated for 8ohms and 6 ohms. the tweeters i will be using are 16ohms. will this be alright or would i have to use a different crossover?
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Old 10th September 2013, 03:10 PM   #33
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I remember reading jbell used drivers were also 16 ohm and he still considered the cab to be 8ohm nominal inpedence. I will work very well. Don't forget to post some pics.
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Old 10th September 2013, 08:49 PM   #34
Xoc1 is offline Xoc1  United Kingdom
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Pabesco
You already own an active crossover. If you have a suitable amplifier for the HF drivers then you should use that in preference of a passive crossover.
The passive crossover suggested will not work properly with the 16 ohm tweeters.
Going active allows you far more accurate control of the crossover frequency and will give you better audio quality. Looking back over this thread the crossover frequency suggested is 1.9Khz. Even this is quite high for a horn loaded mid.
(Grecon used a passive 1.9kHz passive crossover in his cabs, but he made his own crossovers to suit the differing driver impedances.)
Regards Xoc1
PS Are your TH18 cabs working OK?
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Old 10th September 2013, 09:38 PM   #35
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Xoc1,

My suggestion was to always add an internal xover. I wasn't suggestion only use the internal one. I have used the mentioned crossover as a replacement for other speakers and it works quite well. If you read the designers statement (jbell) he considers the cabinet to be 8 ohms even with the 16ohm tweeter.

As to the th18, it is an awesome subwoofer design as it should be because it's so similar to the ss15 folding.
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Old 11th September 2013, 08:06 AM   #36
Pabesco is offline Pabesco  Bahamas
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Thank you xoc1. I will use the active crossover and see how that works. I'm using one half of a qsc 2450 to run the two mids I just built. The other half of the qsc is just running some highs (two small boxes filled with six tweeters each)

Thanks for the info guys. The speakers should be here by next week and I wil post the results ASAP.
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Old 7th January 2014, 10:01 PM   #37
Pabesco is offline Pabesco  Bahamas
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Hi guys just a quick question for these tops, some of the suggested items are not available at this time and I would like to know which would be the best combination for the best sound from thers tops.
I am planning to use the following
DAYTON AUDIO PA310-8 12
SELENIUM D220ti-16
GOLD WOOD GM500PB
I will not be stacking and does anyone think I should use the Dayton audio h10rw Round waveguide seeing the 12 inch is not available. Or should I use the Dayton audio H6512 waveguide
I just want to get the best possible sound from these tops.
Thanks guys.
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Old 7th January 2014, 10:09 PM   #38
Pabesco is offline Pabesco  Bahamas
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I forgot to ask another question. I am adding a DBX drive rack pa plus and most likely removing the eq and active crossover from the system , will I now have to add passive crossovers to these tops to get the proper sound or will the driverack tack care of this.
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Old 3rd April 2014, 09:42 PM   #39
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Quote:
Originally Posted by Pabesco View Post
Hi guys just a quick question for these tops, some of the suggested items are not available at this time and I would like to know which would be the best combination for the best sound from thers tops.
I am planning to use the following
DAYTON AUDIO PA310-8 12
SELENIUM D220ti-16
GOLD WOOD GM500PB
I will not be stacking and does anyone think I should use the Dayton audio h10rw Round waveguide seeing the 12 inch is not available. Or should I use the Dayton audio H6512 waveguide
I just want to get the best possible sound from these tops.
Thanks guys.
I'm also interested in the answer to these questions.

Did you get a response? Have you started the build?
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Old 7th April 2014, 03:38 PM   #40
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Hello, if I may butt in with some general suggestions....

If your intended use is for pro audio, the Dayton round waveguide is going to send a lot of energy where you don't need it, like to the ceiling & floor. Plus, you won't get a lot of distance from it, because it's both shallow & wide in all directions. Something deeper & closer to 40 degrees vertical would work better.

Placing your horn/driver on top of the box doesn't matter much if you're not creating a line array.

Using an 8 Ohm passive crossover with a 16 Ohm compression driver will shift your crossover point by an entire octave. The amplifier sees the impedance of the 8 Ohm woofer as nominal, not the highs.

1600Hz is closer to a realistic crossover point for a 12" cone, although it may not even play that high horn-loaded because the front chamber tends to act as a lowpass filter. Build, listen & measure for yourself.

Unless I misinterpreted, you don't want to use both a passive crossover & an active crossover at the same time. It can only sound bad. An internal switch or patch would be necessary to bypass the passive network.

Pabesco, your component choices look good, but make sure the horn doesn't have a squared-off throat after the mounting threads, as many budget horns have. They tend to sound a bit harsh. You might consider spending a little more on a better horn.

I'd like to see some build pics, too!
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