Maelstrom redesign, comments? (1 Viewer)

[JohnA]

I have been living with my Maelstrom in a sealed 22" cube and like it. So far, it performs very well as far as I can tell.

I have yet to finish the enclosure (veneer, etc) and have come to conclusion that cosmetically, the enclosure would look better if I had a downward firing driver. It is currently a front firing driver configuration.

The enclosure could be up to 30" tall. I am using a 250 watt plate amp. I primarily use it for HT and like the hard hitting bass.

Should I keep the 22" square and just add another 8" to the height or would I better off with a bigger or ported (or bigger and ported) enclosure? Will any of these changes give me "better bass" or a better performing subwoofer? Should I keep a 22" cube?

Any comments or specific recomendations are appreciated.

Thanks.

 

[Geoff L]

I have not run the numbers, but if you add volume, (interior volume) to the current sealed cabinet the, Q is going to change and this will affect it's Sealed Sound (if the interior volume change is large enough).

The adding of a base plate or down firing postion will have little or no effect on performace assuming the interior volume and power stay the same.

Going ported or PR'ed now thats a different store...Until you run some programs/sims, or get some user feedback, all I can say is,,,,properly ported is going to get you more spl per watt & should provide better spl deep extension.

Never have used the Driver so have no suggestions on cab design or size. Others might be able to address that for you much better (with some actual user info), which obviously is what your looking for.

Regards
Geoff

 

[Mike Keith]

I like the Maelstrom in a larger box, about 200l to 250L, this works well for both sealed or ported. I have 2 in a 245L sono and they sound great for both music and movies.

http://www.geocities.com/kingdaddyke...s.html?1078331

 

[TrentT]

I have two Maelstrom's, each one in a ported box, each with a volume measuring just over 11 cubit feet. Ports are dual 4" in each (from Adire). Power is supplied by a QSC EX2500, providing each voice coil with 375 watts RMS (1500 watts total)
I have spoken to the designer / builder of this driver, and I was told that it was designed to be used in a ported design. Also, it is designed as a downfiring driver.
I tried the subs my boxes before they were ported, and they were OK, but nothing compared to the ported design. The bass I get in my 13x23 room is scary. Not only high SPL, but the detail is great, and so is the response. Impact is amazing. Low end extension is very good. They will crush your chest at 20hz.
I would highly recommend going to a ported, downfiring design, and put it in a corner.
My use is 99.9% home theater. In my setup, some music can get a little boomy, but that can be solved with a lower x-over point. Not a problem for movies at all.
Overall, I am very happy with the Adire product in the ported boxes.
Oh, and even with all that power, I have never bottomed the drivers. And I run them pretty hard.
Good luck.

 

[JohnA]

Thank you for the suggestions and comments. I am considering using one of the ported reference designs.

When I originally planned and began the Maelstrom build, these where not available.

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[Kyle Richardson]

Ported Maelstroms are great and with 250 watts you'll be surprised at how loud it will get.

 

[dave alan]

Quote:

I like the Maelstrom in a larger box, about 200l to 250L, this works well for both sealed or ported. I have 2 in a 245L sono and they sound great for both music and movies.
______________________________

I'm not familiar with the Maelstrom driver, but I've found all of the Adire drivers I've used to date (6 drivers and counting) to be as good as low frequency transducers get.

MK...I have to say that this sub you've designed and built is easily one of the most original and beautifully executed DIY subs I've ever seen.

Congratulations on a superb job!

I've seen the sub and mains posted before, but I never tire of seeing that sub. It should be a permanent post in the DIY section as an example of what can be achieved with a plan, patience and determination...really.

Dave

 

[Mike Keith]

Wow Dave, I might have to frame your post so I can look at it any time I need an ego boost, thanks for the compliment. I was pleasantly surprised how well the closed port valve worked for music, these drivers can pump out incredible bass well down below 15 Hz in room. Since I upgraded my Pre/Pro I can reach considerably louder levels without any of the drivers bottoming out like they would before, and it’s so clean and smooth, I’m a Adire fan for life now.

Cheers
Mike

 

[Greg Monfort]

Out of curiosity I ran the numbers for an 18Hz pipe and got reasonable gain/impulse response with 10.83ft^3 which equates to 53.5" i.d. high, vent = 6" dia x 12" long. When I recalc it at 30" i.d. this pushes the pipe's tuning up to 32.1Hz so the vent length increases to 28", acoustic gain falls ~4dB by 20Hz, and the impulse response degrades considerably.

If you can't tolerate the length, then a golden or acoustic ratio cab and PRs is your best option for vented since the vent will be even longer.

GM

 

[Mike Keith]

I wouldn’t get over 9ft3 for a vented enclosure with the Maelstrom. I tried several test enclosures (2 different sizes at a time) and found that a box over this amount didn’t sound as good, the bass had no punch at all, possibly a bit too over dampened. At least that was my listening impressions.

 

[Greg Monfort]

>I wouldn’t get over 9ft3 for a vented enclosure with the Maelstrom........possibly a bit too over dampened.
====
Hmm, too much Vb for a given Fb causes an underdamped alignment, i.e. peaking (ringing) at Fb in this case and why it didn't sound as good. Of course you can damp this down to a critically, or even overdamped alignment, but as you noted, not a good plan.

Anyway, dropping down to 9ft^3 in my pipe design reduces output ~3dB/20Hz (making it severely overdamped) and requires a 17" long vent, so not good advice IMO with this particular design.

GM

 

[Kyle Richardson]

For the longest time I ran a Maelstrom in 10 cu ft tuned to 21Hz and LOVED it! There was not peaking at all at Fb and with room gain it was flat to about 19Hz IIRC.
Actually, what impressed me most about this sub was how musical it was and how well it blended with the mains when calibrated properly. Many, many people I performed demos for also agreed it was great with music and killer for HT.
Correct, it was not a punchy bass, but I designed it to perform best from 60Hz down and was not after punch. If one is wanting punch then I agree that this alignment is not the proper choice and a smaller enclosure needs to be made. Thats the beauty of DIY....design it for YOUR needs and YOUR wants

 

[Greg Monfort]

Understand though that a 'punchy' bass alignment normally is an underdamped one, i.e. peaking above Fb in this case. For max punch in an otherwise highly damped alignment, what Wayne Parham calls his 'Pi Alignment' is the Hot Ticket, but since it only emphasizes the midbass (great for bass, kick drums) then either a true sub system or digital EQ (if there's enough excursion) is required if not stuck in the corners.

For instance, a Maelstrom in ~4.65ft^3/26Hz Fb has an output that's off the 100dB plot limit from ~65-165Hz, but is -24dB/~22Hz referenced to ~65Hz. In a HIFI/HT app, this is some serious 'slam'.

GM

 

[Mike Keith]

Well you guys know more about theory then I do, I'm probably confused about over-damped and under-damped. But to my ears in a side by side comparison I found the 245L (under 9ft3) to sound better then the 300L and 350L sonotubes by a good margin, also I had problems with the 6" port, too much noise at Fb so I went with a 8" port tuned to 19Hz.

 

[JohnA]

Some good info here.

If I go with one of the reference designs, either the SBB4 or EBS alignment, is there a need for more than 250 watts?

I am looking for bass that shakes the house on DVD's like Lord of The Rings: Return of the King.

Thanks

 

[minhG]

well how big is your house?

hmm, it doesn't matter, a maelstron in the EBS or SBB4 alignment will shake a very large house...

 

[Kyle Richardson]

Yes sir, you are correct

 

[JohnA]

I am glad to hear that I won't need to consider a new amplifier.

Is there such a big difference between the large ported designs and my sealed 22" cube, or have I become used to the Maelstrom?

The Maelstrom is placed in a corner on a first floor, open concept, No internal doorways or walls on the first floor other the staircase in the center of the house. This has a wall on either side of it.

First floor measures approximately (by memory) 22' x 34' x 7'-6".

 

[Kyle Richardson]

With a room that large you may need the extra output down low that the ported design provides. Try it in a test box and I'll be you will be pleased.