Implementing the SW-12-16FR servo open baffle subwoofer driver

WerTicus · « **Reply #40 on:** 2 Jun 2008, 05:23 pm »

Thanks, emailed.

richidoo · « **Reply #41 on:** 3 Jun 2008, 02:25 am »

Danny, thanks for bringing this cool new driver system to market. I'm looking fwd to trying it out. Already got my shopping cart loaded!

I would like to use my modified Behringer DCX2496 digital crossover to make a 2 way with Feastrex D5nf. The driver is only 4" dia, so it starts rolling off kinda high. Here is a simulated OB FR, (thanks to Martin King Quarter Wave software):

I would like to be able to experiment with 2nd and 4th order crossover slopes, crossing at freqs from 150Hz up to about 250Hz tops. I think the internal crossover in the plate amp will not be as flexible or precise as the digital crossover, so is it possible to disable or bypass the internal crossover to allow external bass management? If so, what is the maximum unattenuated frequency the plate amp can play? Is there any danger in playing these drivers/amp too high frequency? My peerless drivers don't seem to mind playing to 1k, but they are passive, of course.

I want the final crossover freq to be as low as possible, but I don't know how much boost I can give the main driver until I start experimenting. It would be good to know there is some flexibility in case it prefers a steeper slope at a higher frequency.

Danny, sounds like from your experience it does play pretty high... -6dB at 300Hz is way more than implied by the controls and specs - or am I missing something? Is that in the external crossover mode?

I think it will make a sweet combo!
Thanks for any advice.
Rich

Christopher Witmer · « **Reply #42 on:** 3 Jun 2008, 11:39 am »

Rich, you devil you! aa

-- Chris

Danny Richie · « **Reply #43 on:** 3 Jun 2008, 09:27 pm »

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Danny, sounds like from your experience it does play pretty high... -6dB at 300Hz is way more than implied by the controls and specs - or am I missing something? Is that in the external crossover mode?

That's using the Direct Servo plate amp with the crossover setting turned all the way up, not an external mode.

Brian is coming up this weekend and we are going to be doing some measurement taking to see where in fact all this is and adjust gain levels set on the amps.

richidoo · « **Reply #44 on:** 4 Jun 2008, 01:15 am »

Thanks!!!

WerTicus · « **Reply #45 on:** 5 Jun 2008, 06:17 pm »

See my thread about the Tripple Woofer W open baffle for instructions on how to build it (updated as I build it)

http://www.audiocircle.com/index.php?topic=56491.0

Fatawan · « **Reply #46 on:** 5 Jun 2008, 09:13 pm »

I am intrigued by this triple driver OB woofer setup. What kind of numbers would it put up with a single amp? What if you used 3 amps, how would it differ? How low could it go and at what SPL?

Last but not least, how would it work with the LS6's?

Danny Richie · « **Reply #47 on:** 6 Jun 2008, 01:52 am »

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I am intrigued by this triple driver OB woofer setup. What kind of numbers would it put up with a single amp?

Judging by the output I am getting from a pair of them I'd say a lot.

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What if you used 3 amps, how would it differ?

DCR of each woofer is right at 12 ohms. So paralleling them on the one amp gets the most output from that amp. The amp does not produce as much power at the higher impedance load of driving only one woofer.

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How low could it go and at what SPL?

They will go flat to 20Hz and even a little less. SPL levels, plenty.

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Last but not least, how would it work with the LS6's?

Very well.

WerTicus · « **Reply #48 on:** 6 Jun 2008, 04:01 am »

you wouldnt put more amps per set of subs, you'd put more sets of subs and single amps

I've starting building this thing today ... just one for now, and if i feel the need ill add a second later.

sts9fan · « **Reply #49 on:** 6 Jun 2008, 01:41 pm »

How would this work with two drivers? Is this more of a space saving configuration vs an H baffle? I am thinking of building a pair of speakers with two of these per side in this configuration.

Kris

Danny Richie · « **Reply #50 on:** 6 Jun 2008, 02:05 pm »

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How would this work with two drivers?

See pics on page 1. It works great! This is the best sub bass I have heard to date.

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Is this more of a space saving configuration vs an H baffle?

This design is structurally sound and very stable, maybe more so than an H frame. It is also shorter and in the application I am using it in I needed it to be shorter.

TRADERXFAN · « **Reply #51 on:** 9 Jun 2008, 03:47 pm »

Quote from: Danny on 3 Jun 2008, 09:27 pm

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Danny, sounds like from your experience it does play pretty high... -6dB at 300Hz is way more than implied by the controls and specs - or am I missing something? Is that in the external crossover mode?

That's using the Direct Servo plate amp with the crossover setting turned all the way up, not an external mode.

Brian is coming up this weekend and we are going to be doing some measurement taking to see where in fact all this is and adjust gain levels set on the amps.

Looking forward to seeing what you discovered with this...

richidoo · « **Reply #52 on:** 10 Jun 2008, 11:46 am »

ditto aa

thanks
rich

Danny Richie · « **Reply #53 on:** 10 Jun 2008, 10:57 pm »

Brian took a lot of measurements and confirmed mine.

He then made adjustments to the input gain stage to allow the amps to work more easily with the average output levels of most pre-amps and amps.

We also really cranked some stuff up and had a blast.

TRADERXFAN · « **Reply #54 on:** 11 Jun 2008, 12:24 am »

Quote from: Danny on 10 Jun 2008, 10:57 pm

Brian took a lot of measurements and confirmed mine.

He then made adjustments to the input gain stage to allow the amps to work more easily with the average output levels of most pre-amps and amps.

We also really cranked some stuff up and had a blast.

-What did you run for mains?

Danny Richie · « **Reply #55 on:** 11 Jun 2008, 02:11 am »

First we used a pair of Neo-1's. That's one of the new little giant killer mini-monitors. Then we set up a pair of OB-7's with M-130X woofers in the lower end. Bass was really clean and tight to say the least.

Danny Richie · « **Reply #56 on:** 14 Jun 2008, 04:56 pm »

W frame cabinet plans have been posted.

http://www.gr-research.com/pdf/obsub.pdf

The guys that build these are going to be really pleased with just how well it sounds. This sub is really, REALLY, good.

TRADERXFAN · « **Reply #57 on:** 14 Jun 2008, 05:12 pm »

Thanks for posting the plans... I was just staring at the picture this morning trying to deduce just exactly how to put it together

My order should prob be delivered in time for me to start on this next weekend!

TRADERXFAN · « **Reply #58 on:** 14 Jun 2008, 05:19 pm »

Looking it over, you didn't really specify placement of the drivers in the panels... it looks like you have them set back as close to the corner as possible though. That's the important point, correct? -to keep them in very close proximity?

Also, the front to back placemnet of the woofer wedge in relation to the depth of the frame isn't specified. Is that supposed to be about equally set in from the outside edges?

Danny Richie · « **Reply #59 on:** 14 Jun 2008, 05:37 pm »

This one is actually pretty easy to build.

If you really wanted to get creative you could use thicker material, double up on the baffle thickness holding the woofers (flush mounting them), or line the insides with no Rez to make it more solid.

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Looking it over, you didn't really specify placement of the drivers in the panels...

I jut added that. Sorry, I forgot those measurements at first.

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Also, the front to back placemnet of the woofer wedge in relation to the depth of the frame isn't specified. Is that supposed to be about equally set in from the outside edges?

If you center it then you have very little space left front to back either way. It just fits.