OTop 12 and Compression driver choice, XO

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Symphonicmind
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OTop 12 and Compression driver choice, XO

#1 Post by Symphonicmind » Thu Jun 27, 2019 12:46 am

Hi Everyone,
We want to build 4 OTop 12 with compression driver. In the plan, Bill said we can use PSD2013 together with 1.2kHz XO. The woofers we have are Delta Pro 12A
I want to ask several questions (Sorry for noob questions):

1. Can I use my available PSD2002-8 with Eminence PXB2:1K6 XO? It has 12dB/Oct LP and 18dB/Oct HP
2. With PSD2013-8 (which we have to wait a month to order), can we use the same PXB2:1k6 XO?

I am worry a little that if I use 1.2kHz 3rd order HP for PSD2013, it may destroy itself in high SPL playback situations.

Please help me.
Thank you very much.

Edwards

Grant Bunter
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Location: Ilfracombe Queensland Australia
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Re: OTop 12 and Compression driver choice, XO

#2 Post by Grant Bunter » Thu Jun 27, 2019 3:41 am

Hi, and welcome to the forum :)

Forget any off the shelf filters. No, don't go ahead and ignore this comment lol.
Build the ones listed in the plans, as they will make the cabs sound even better.
Use the HF components listed in the plans. it's not just about power handling, it's about size too.

If you're worried about blowing HF components with high SPL, you may not be aiming at building enough cabs...
Built:
DR 250: x 2 (melded array) with March 2012 plans. 2 more under way with CD horn
T39's: 4 x 20" BP102 , 2 x 28" 3012lf.
WH8: x 3 with melded array.
Bunter's Audio and Lighting "like"s would be most appreciated...

Symphonicmind
Posts: 15
Joined: Mon Apr 09, 2018 7:19 pm

Re: OTop 12 and Compression driver choice, XO

#3 Post by Symphonicmind » Thu Jun 27, 2019 5:10 am

Grant Bunter wrote:
Thu Jun 27, 2019 3:41 am
Hi, and welcome to the forum :)

Forget any off the shelf filters. No, don't go ahead and ignore this comment lol.
Build the ones listed in the plans, as they will make the cabs sound even better.
Use the HF components listed in the plans. it's not just about power handling, it's about size too.

If you're worried about blowing HF components with high SPL, you may not be aiming at building enough cabs...
Thank you. I have a space with 100 square meters total area. I tend to build 04 OTop 12 there. I will listen to your recommendation and build the recommended 1.2kHz XO with PSD2013-8 and Delta Pro 12A.
How many volt I can safely drive and limit the OTop12 with that configuration? I dont need to war volumne. I just want to have some specific number to remember that I should never go pass that point.

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Bill Fitzmaurice
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Re: OTop 12 and Compression driver choice, XO

#4 Post by Bill Fitzmaurice » Thu Jun 27, 2019 6:44 am

viewtopic.php?f=3&t=25249

This information is in the latest iteration of the plans. Being sure that you're not working with old information is why it's recommended that you always get an update before building.

Symphonicmind
Posts: 15
Joined: Mon Apr 09, 2018 7:19 pm

Re: OTop 12 and Compression driver choice, XO

#5 Post by Symphonicmind » Thu Jun 27, 2019 8:39 am

Dear Bill,
The plan I bought was from 2018. It said there are 2 options for 1.2KHZ XO which are PSD2013 and NSD2005.

Now NSD2005 is discontinued. I also dont have plan to use it either.

I prefer PSD2013-8 over NSD and want to use PSD2013 on my OTop 12.

Is it still valid choice for HF driver?

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Bill Fitzmaurice
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Re: OTop 12 and Compression driver choice, XO

#6 Post by Bill Fitzmaurice » Thu Jun 27, 2019 9:25 am

As I said, before starting a build get a plans update. If you had you would have seen that the PSD-2013 is no longer listed as a recommended driver. It was previously listed as a lower cost option to the NSD. The F151M-8 is smaller, lighter, and works as well as the PSD at the same price, so there's no reason to recommend the PSD anymore.

Symphonicmind
Posts: 15
Joined: Mon Apr 09, 2018 7:19 pm

Re: OTop 12 and Compression driver choice, XO

#7 Post by Symphonicmind » Fri Jun 28, 2019 10:39 am

Thanks Bill. I have sent you message regarding the plan update. I hope you will sent the updated plans. If I need to order OT12 again to receice the update please let me know.

Thank you.

Grant Bunter
Posts: 6121
Joined: Mon Nov 28, 2011 11:12 am
Location: Ilfracombe Queensland Australia
Contact:

Re: OTop 12 and Compression driver choice, XO

#8 Post by Grant Bunter » Fri Jun 28, 2019 3:30 pm

Symphonicmind wrote:
Thu Jun 27, 2019 5:10 am
How many volt I can safely drive and limit the OTop12 with that configuration? I dont need to war volumne. I just want to have some specific number to remember that I should never go pass that point.

I understand you want a number, but it's not really relevant.
Why?
Because you will hear distortion in your cabs before you reach that number.
And if you hear distortion, you must turn down...
Built:
DR 250: x 2 (melded array) with March 2012 plans. 2 more under way with CD horn
T39's: 4 x 20" BP102 , 2 x 28" 3012lf.
WH8: x 3 with melded array.
Bunter's Audio and Lighting "like"s would be most appreciated...

Symphonicmind
Posts: 15
Joined: Mon Apr 09, 2018 7:19 pm

Re: OTop 12 and Compression driver choice, XO

#9 Post by Symphonicmind » Fri Jun 28, 2019 8:01 pm

Grant Bunter wrote:
Fri Jun 28, 2019 3:30 pm
Symphonicmind wrote:
Thu Jun 27, 2019 5:10 am
How many volt I can safely drive and limit the OTop12 with that configuration? I dont need to war volumne. I just want to have some specific number to remember that I should never go pass that point.

I understand you want a number, but it's not really relevant.
Why?
Because you will hear distortion in your cabs before you reach that number.
And if you hear distortion, you must turn down...
Thank you. I really appreciate your help.

I have read about Eminence ring radiator CD F151M-8 that Bill told to replace NSD2005 in Otop 12. I dont understand one thing:

How a CD with high Fs 1.03kHz can handle 1.2kHz 18dB/Oct crossover together with Delta pro 12 or 3012HO?

I have a pair or B&C DE250 and PSD2002 free now. So, if F151M-8 can handle that XO, will BC DE250 and PSD2002 be acceptable?

Ed.

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Bill Fitzmaurice
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Re: OTop 12 and Compression driver choice, XO

#10 Post by Bill Fitzmaurice » Fri Jun 28, 2019 8:56 pm

The DE250 should be fine, the 2002 I've never really cared for.

Symphonicmind
Posts: 15
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Re: OTop 12 and Compression driver choice, XO

#11 Post by Symphonicmind » Sat Jun 29, 2019 2:28 am

Thanks Bill very much.

Ed.

jeremydta
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Re: OTop 12 and Compression driver choice, XO

#12 Post by jeremydta » Tue Oct 01, 2019 10:14 pm

Sorry to hijack this thread, but I am in a similar position. The PSD2013 has a much higher power rating compared the the F151 (80 vs 45W). Does that mean it will go louder and or be more durable to blowing? thanks, Jeremy

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Bill Fitzmaurice
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Re: OTop 12 and Compression driver choice, XO

#13 Post by Bill Fitzmaurice » Wed Oct 02, 2019 7:00 am

Yes, but there's nothing to be gained by a HF section that goes louder than the LF section. Between the higher sensitivity of the HF section compared to the woofer and the power density reduction of 3dB for every octave increase in frequency the power capacity of the HF driver doesn't need to be even 10% of that of the woofer.

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