[Rclark]

 I'm still tossing sub ideas around. Still might do my Brahma's as OB, but that will require some work and might in the end cost as much, or near enough as the sub in the link below, with having to buy an EQ, external crossover, flatpacks, quality amp, etc. And then it still might not work.

http://www.rythmikaudio.com/FV12.html

 New Rythmik ported 12 for $499  Flat to 20, goes to 14hz. Servo controlled.

 Now I know you guys generally don't like ported subs, but I gotta say it, my little ported 10 kept right up with my MMG's. Now it's not a dream sub by any means, but it certainly didn't sound "slow" or "bloated", on the contrary, it sounds tight and musical.

 Again, my amp is high passed at 80hz, my Maggies are not doing any bass, I think this is possibly the key to the great integration of my ported sub and maybe if I was running my MMG's full range I'd be having a different experience.

Now I've never run a sealed sub, or an ob for that matter, and I get why they can be better than ported. I've also run a couple small ported subs in the past that were awful. But mostly ported subs have been a good experience.

 Consider that these are also servo controlled so should have that extra degree of control, heck, they're a Rythmik.

 Should I go for it next month? Pick one up, try it for the 30 days, pick up a second and go from there?

 Ideally someone will step forward with an OB calculator of some sort I can use to make my Brahma's work, but nobody has one, so that is a bit daunting. I'd much prefer an OB setup, as it should match the modded MMG's better, and will be less offensive to neighbors, but I don't get any complaints now with my ten, so maybe a slew of these things is what I need. Start one, add another, later add two more.

 Just talking out loud, but I have to make decisions soon on my subbass situation.

[2gumby2]

I built a couple of Rythmik subs and while I found the bass quality to be fine they just could not provide the output I was looking for. I've been very happy with my Elemental Designs A5s subs though. Nice bass quality and good output.

[jtwrace]

 New Rythmik ported 12 for $499  Flat to 20, goes to 14hz. Servo controlled.

Not really...you must measure in your room and see what it goes to. 

[josh358]

I wouldn't go with the ported. They offer a sealed version for not much more. Give yourself a Christmas present, it will sound better.

They also have plans for a dipole sub somewhere, but I can't find them today.

Or maybe look for a used sealed Martin-Logan (the new ones aren't sealed and by all accounts they aren't as good).

[SteveFord]

http://www.audiocircle.com/index.php?topic=92003.0

[milford3]

The Aperion 12D is more money but I conur that a sealed unit is better.

http://www.aperionaudio.com/product/NEW-Bravus-IIa-12D-Powered-Subwoofer,304,66,856.aspx

[Thebiker]

Save more money and get a REL.  MHO, they are the best.

[jk@home]

I use these diy sealed Rythmiks nearfield in my MMG system (along with some IBs ), but have to agree that they aren't the highest output subs out there. Fine for me though as mid bass subs. These are the non-servo drivers, made by TC Sound, that Brain Ding sold before going to all servo models. Using a pro x-over and pro amp to drive.

If you can diy, check into these GR/Rythmk open baffle subs.



http://www.audiocircle.com/index.php?topic=54875.0

http://www.google.com/#pq=gr+rythmik+open+baffle+subwoofer&hl=en&cp=13&gs_id=e&xhr=t&q=GR+Research+Rythmik+open+baffle+subwoofer&pf=p&sclient=psy-ab&rlz=1C2CHMA_enUS358&source=hp&pbx=1&oq=GR+Research+Rythmik+open+baffle+subwoofer&aq=f&aqi=&aql=&gs_sm=&&fp=1&bav=on.2,or.r_gc.r_pw.,cf.osb&cad=b

Simple as buying & cutting some mdf (you can rent a table saw for a day if need be). Then coat the cabinets with Duratex roll on speaker paint.

[jtwrace]

If you can diy, check into these GR/Rythmk open baffle subs.

Yes, but do not build them as shown...

[jk@home]

Well I grabbed a pic off the net, what did this individual do wrong?

To the OP, have you asked for help using the drivers you have over at the Open Baffle section?

[josh358]

If you can diy, check into these GR/Rythmik open baffle subs.

I followed a link on one of your URL's and it looks like someone is selling a beautiful pair:

http://www.audiocircle.com/index.php?topic=99493.0

I'd also suggest looking at the H-frame dipole woofer plans on Linkwitz's site, not sure how they compare to the Rhythmiks.

[jtwrace]

I followed a link on one of your URL's and it looks like someone is selling a beautiful pair:

http://www.audiocircle.com/index.php?topic=99493.0

I'd also suggest looking at the H-frame dipole woofer plans on Linkwitz's site, not sure how they compare to the Rhythmiks.

Yes those are a deal!

[Rclark]

 I did some more reading on the FV12. It appears they took into consideration what people don't like about ported subs and inserted a great deal of control onto the amp:

"Vented subwoofers do have more phase delay at the low end frequency spectrum. That combined with poor room acoustics sometimes produces boomy bass sound. We have variable extension frequency and damping settings to address that. Customers should experiment with extension filter settings. A high damping setting can produce a tighter sound compared with a low damping setting. "

"With many subwoofers, it is difficult to get a correct and seamless integration with the main speakers because the amplifier settings are often very different to the measured response. You may set the crossover point to 80 Hz, but the actual crossover point may be anywhere between 60 and 100 Hz! The crossover control knob on our plate amplifier can serve as a fine tuning tool to reduce the overlap in output between the main speakers and the subwoofer."

"All of our subwoofers feature unique bass extension controls which are not normally provided on subwoofers. This enables the user to customize the output and extension to achieve the best compromise in any room. Most subwoofers neglect to provide bass extension control, and the result is that dynamic headroom is compromised. "

"The bass extension controls enable the user to customize the frequency response of the low end. This puts control back in the hands of the user. The controls customize a high pass filter, which attenuates frequencies below a given frequency. If set to 14 Hz, bass below this point will be filtered. The damping control determines the slope, low damping providing the steepest slope."




"The following three figures show the actual frequency response for all 3 damping settings when the frequency is set to 14 Hz, 20 Hz, and 28 Hz. The low damping setting provides a boost up to 1.5 dB whereas high damping provides a most smooth and gradual roll-off.They give a total of 9 different roll-off characteristics." 








 Does this change things? to me, this looks like a very neat subwoofer and the price is very right. PS I am totally not concerned with SPL levels. I listen at 70-80dB at most, 90+ for very short periods. This sub is sounding more and more badass as I read about it.

 That guy selling the OB's, he's just selling his old gen 1 drivers and the amps, and not the enclosures, so that does me no good.
 

[Rclark]

I built a couple of Rythmik subs and while I found the bass quality to be fine they just could not provide the output I was looking for. I've been very happy with my Elemental Designs A5s subs though. Nice bass quality and good output.

 Totally intrigued by that response though. Your ED's sound as good as servo? The A3s-300's are $300 a piece, shipped, when you buy a pair... but you have to wait 2 months to get them.


 And JK@home, your maggies look badass, you have some skills! Our setups are likely to be very similar in the end.

[jtwrace]

That guy selling the OB's, he's just selling his old gen 1 drivers and the amps, and not the enclosures, so that does me no good.

TomS who is selling the OB's is NOT selling just amps and drivers.  He is selling the whole package. 

[Rclark]

Yeah but not shipping.

[jtwrace]

Yeah but not shipping.

right.  They fit in vans, trucks.....

[Rclark]

I'm basically in Seattle, he's in Indiana. I get 14 mpg. Lol. I hate how all you audiophiles live east. I got nothing out here, NOBODY is into stereos where I live.

[josh358]

To be honest, I'd go with the sealed ones (assuming the OB's are out). I've just never heard vented subs that were as tight as sealed ones. Lots of explanations for that, from the inherent linearity of the air to the group delay they mention. Not to mention that a vented sub has a delayed backwave, which is going to introduce some time smear. And there's port noise as well.

This is why they market their ported subs as "home theater" subs, and the sealed ones as "audiophile subs."

Increasing the damping as they suggest may indeed improve the group delay performance, but it will likely do so at the cost of low frequency extension.

Of course, I can't say that for sure without having heard them, but I think you'll find that it's a pretty universal observation that sealed subs mate better with planars than ported ones.

[Rclark]

Well, lol, you'll notice below they also use the term audiophile. I get it, ported subs are generally derided. Something tells me this one might be one of the better ported subs out there. You've got the servo, you've got the varying slopes, and they show you how to set up to minimize phase issues further, and if I were to do it, I'd be ultimately running 4 of them, so certainly no danger of port noise and such, especially at my listening levels. I don't even get port noise from my 10. I just don't push it that hard.

 Definitely have time to toss around ideas and talk about it. Sure hate to put the brahma's to waste. Heck, ultimately the best solution might just be a couple sealed box flatpacks and a couple amps for those big 15's.

 The first purchase after my speakers is the Omnimic, and I plan on spending a week just measuring and getting comfortable with all the bells and whistles.