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Old 18th April 2013, 12:53 PM   #3721
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Quote:
Originally Posted by Saturnus View Post
Sadly, checking back the filter posted earlier is for use with Eminence Basslite S2010.

Here is the correct filter for use with the HP10W.

http://www.diyaudio.com/forums/attac...boomfilter.jpg

Hi

Saturnus, you kindly worked out the correct filtering to use the HP10,s and the PHT-407N's and posted this diagram.

this was originally created for a query from someone who wanted to build using an AMP9. AMP9 has 4 channels, if I wire this into 2 channels in an AMP6, I am effectively wiring the tweeters and woofers in parallel, and by my calculations, the amp will see a total of 2ohms...... Can an AMP6 operate OK at 2 ohms, it seems to be rated to 4 ohms min........ I may not know much, but I know enough to know that I'll fry my amp if I get this wrong.......

BJ
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Old 18th April 2013, 01:09 PM   #3722
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Quote:
Originally Posted by brummiejon View Post
... and by my calculations, the amp will see a total of 2ohms
No. It's still 4 ohms. That's what a filter does

I still highly encourage to use active filters (analog or digital) if you're not using a piezo.
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Old 18th April 2013, 01:17 PM   #3723
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Cheers, now your putting the cat amongst the pigeons.......

I've only ever use active crossovers with bi or tri amping..... how does an active filter work? and where do I get one or how do I make it?

BJ
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Old 18th April 2013, 02:53 PM   #3724
soren5 is offline soren5  Denmark
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I've decided to build a half boominator with the S2010 and PHT-407N. I was searching through the thread for info about the the boominator box alignment and found this:
Quote:
Originally Posted by Saturnus View Post
[...] And then a little trick I discovered after having built several test cabinets. If you calculate a standard optimal bass reflex cabinet for whatever driver you use with the optimal Q=0.7 tuning, and you then divide Vb with PI, and multiply Fb with the squareroot of 2, you end up with the optimum tuning for outdoor use Q=1.2, and you get rid of all those bass frequencies you can't play loud enough to be audible outdoors anyways, and at the same time the rise towards the cut-off frequency equalizes the bass to a more or less flat level when used outdoors.
If I follow these steps, it appears to me that the S2012 should (or could) be in a somewhat smaller box compared to the HP-10W. Am I doing something wrong? I'm not sure what the optimal Q=0.7 tuning is for the S2012, but Eminence's own recommendation enclosures compared fairly well to WinISD box alignment QB3, so I figured this must be close to the standard Q=0.7 tuning. Here are my calculations:

Eminence own recommended box for 2 x S2012 (size M)
Vb = 51 L
Fb = 60 Hz

WinISD box alignment QB3 for 2 x S2012
Vb = 53.46 L
Fb = 57.43 Hz

Boominator box according to above-mentioned "trick":
Vb / π = 17.02 L
Fb * sqrt (2) = 81.22 Hz

Plotting this into WinISD I don't get the same bass extension as the HP-10W, but still an F3 just over 100Hz, which should be okay, right? The reason I'm asking is that I would like make my enclosure smaller if it's possible, without sacrificing too much bass.

Saturnus said earlier in the thread that the S2012 could be used in the original boominator enclosure (Vb = 24), but tuned to 82 Hz. This looks closer the HP-10W transfer function.

In the attached screenshot from WinISD I've also put my own idea to what a box alignment could look like (Vb = 20, and tuned to 89 Hz with an F3 of 100 Hz).

Anyway, what I really want to know is: Would it be possible to reduce the box size for the S2012?

Thanks!
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Old 18th April 2013, 03:34 PM   #3725
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Don't think I ever mentioned the S2012. Instead it's the S2010. Eminence naming (almost) always mentions the VC diameter and nominal diameter. Here 2.0" VC and 10" speaker.

Anyways. For the S2010 I recommend using the exact same box as if you were using the HP10W but dropping 12mm of the length of the port.

I know this isn't exactly the supertuned box as for the HP10W but it's done for getting better bass performance and making what you could call a signature version more versatile so that it can be used indoors (preferably in large rooms) and not just outdoors as for the HP10W.

You could make the box even smaller with the S2010 but it's up to you if you want to make the sacrifice.
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Old 18th April 2013, 04:08 PM   #3726
soren5 is offline soren5  Denmark
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Quote:
Originally Posted by Saturnus View Post
Don't think I ever mentioned the S2012. Instead it's the S2010. Eminence naming (almost) always mentions the VC diameter and nominal diameter. Here 2.0" VC and 10" speaker.
Of course, it should have said S2010 and not S2012. My calcs and sims are based on the S2010. Don't know why I suddenly started writing S2012 instead of S2010

Quote:
Originally Posted by Saturnus View Post
Anyways. For the S2010 I recommend using the exact same box as if you were using the HP10W but dropping 12mm of the length of the port.

I know this isn't exactly the supertuned box as for the HP10W but it's done for getting better bass performance and making what you could call a signature version more versatile so that it can be used indoors (preferably in large rooms) and not just outdoors as for the HP10W.

You could make the box even smaller with the S2010 but it's up to you if you want to make the sacrifice.
Thanks for for clearing that up. So if I build a S2010 half Boominator with a decreased Vb, how far down in volume do you think would be reasonable to go? I'm looking to build a more supertuned box, which will only be used outdoors.

Would it be a bad idea to go all the way down to Vb=17? Perhaps Vb=20;Fb=89 would be a more realistic compromise?

Last edited by soren5; 18th April 2013 at 04:10 PM.
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Old 18th April 2013, 04:50 PM   #3727
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Problem is that the S2010 is actually not a suitable driver for my own supertuning. -2.83dB should be at around at or very near 90.9hz and the +2.83dB peak should be at or near 141.4hz for the supertuning to work perfectly. Bass will be too limited in my opinion with a S2010 using a smaller cabinet than the 27 liters (for 2 drivers) in the Boominator.
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Old 18th April 2013, 05:20 PM   #3728
soren5 is offline soren5  Denmark
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Quote:
Originally Posted by Saturnus View Post
Problem is that the S2010 is actually not a suitable driver for my own supertuning. -2.83dB should be at around at or very near 90.9hz and the +2.83dB peak should be at or near 141.4hz for the supertuning to work perfectly. Bass will be too limited in my opinion with a S2010 using a smaller cabinet than the 27 liters (for 2 drivers) in the Boominator.
Gotcha. Vb for S2010 is of course slightly larger in the Boominator since they take up less space compared to the HP10W. I didn't take that into account when doing the sims. Thanks for the recommendations. I'll buy some parts and keep you updated on the build.
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Old 19th April 2013, 01:27 AM   #3729
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Thumbs down More build pics

Glueing up...... Hard to get perfect
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Old 19th April 2013, 01:32 AM   #3730
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More gluing..... The only place I can do it is in my living room..... I need a workshop......
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