Driver recommendation for a DIY sub... (1 Viewer)

[Mike Lenthol]

I'm looking for a decent 10" at about 0-120$/each, that would be a good performer from a box no larger than 1.2 cu.ft. or so and filling up 30 to 35hz-55hz relatively accurately, of course going lower than "30 to 35" is ok too This sub will be going into a medium room sized about 1800 cu.ft. and for a purely music system. Already have an amp and it has about 170w rms@4ohms to play with.
Also, I forgot what is that word for the ____ distortion... when for example one sub will not sound as good as two subs recreating same volume as one sub. Intermodulation?

 

[Greg Monfort]

Sorry, don't know any.

There are two different distortions reduced by using multiple drivers, amplitude modulation distortion (AMD), and frequency modulation distortion (FMD), AKA intermodulation distortion (IMD), due to the Doppler effect.
For a given signal, two ~identical drivers only have to excurse half as much as one, reducing the distortion caused by any driver non-linearities (AMD), and the LF excursion modulating the harmonics (FMD).
GM
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Loud is beautiful, if it's clean

 

[Geoff L]

Being your looking to fill these freqs only and need to stay small in cabnit vloume you might consider some of the car drivers out today.
Take a look at Image Dynamics low Q drivers. Some Bass List members have recomended the (IDQ 10 and 12).
I was at there site once and cant remember web address. Specs are listed for drivers there.
JL Audio gets some respect there in the small cabnit designs. Stryke has some new drivers designed for small cabnits also.
Sure you will get more ideas from others soon.
Good luck
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Smoothe

 

[Mike Lenthol]

Wow! I was actually just thinking about the Image Dynamics subs Have a pair of 12" in my car and they are very fine speakers that's for sure, but I was usually under impression auto subs were designed in mind with the car's cabin gain which easily can lower F3 of any box a good 10 to 20 hz.
Their subs are really 'weird' though....
same 10" model from Q series available in single voice coil and dual... single offers F3 39hz @ 1.25cu.ft ported, while the dual coil version offers 30hz @ 1.00cu.ft, and same driver in larger box raises the F3?!
http://www.imagedynamicsusa.com/tech..._idq10dvc.html
How should I take this? A typo on their part?

 

[Brian Bunge]

ACI recently came out with the SV10! It is designed for small sealed enclosures around 1ft^3 or so and has a 16mm linear Xmax. The only real downside is that it is not very efficient. They are $199 each. You can check out the driver's specs at the following link.
http://www.audioc.com/subs/ACI_drivers/sv10.htm
Brian
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[Greg Monfort]

>How should I take this? A typo on their part?
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Without crunching the numbers, the lowest F3 will be with a maximally flat alignment, Q = 0.707. Any higher Q (smaller cab), or lower Q (larger cab), will have a higher F3, so I doubt it's a typo.
GM
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Loud is beautiful, if it's clean

 

[Arnold P]

Have a look at the long-throw 10" from Peerless XLS10 (Denmark). From 30 liters this one delivers. Also a passive radiator available.

 

[Chris_Campbell]

Another recommendation for the IDQs. I had two of them in my car and they're nice and tight. Need a good bit of power though (I'd recommend a solid 250 watts apiece).

 

[Dustin Haug]

I have IDQ 10's in my car too. I like them a lot, I'm also running JL 8W6's in my home stereo. You could fit a trio of them in a 1-1.5 ft^3 box. Since you want a really small box you may want to consider seriously using passive radiators.
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My DIY sub page

 

[Mike Lenthol]

Thanks for recommendations peoples So far I'm leaning toward the IDQ 10" DVC. It goes for about 80$ each online and offers 30hz@1cu. foot.
Checked out that Peerless SWR269(XLS10), and from the specs it looks like a good contender, about a 35hz F3 in a cubic foot, but what is the pricing and sources on this one?
Dustin, by the way, why would a passive radiator be better than a port in a small box? Less internal volume displacement?

 

[Patrick Sun]

Mike, PRs work better for small boxes because porting will usually be too long for the small enclosure and can't fit without use of port elbows (if at all).
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PatCave ; HT Pix ; Gear ; Sunosub I + III ; DVDs ; Link Removed

 

[Dustin Haug]

Exactly what Pat said.
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My DIY sub page

 

[Mike Lenthol]

A PR it is then
But are the ones that partsexpress.com carry 'ok' so to speak? They seem to have a foam surround, and overall built so so. Worth spending extra in this area? And do they come with some weights or what's the mechanism on those for tuning?
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With a PR it's also kind of tough to arrange all the components on a box and still make it look classy. Would it be ok to place the active driver on the bottom side, PR on he front and a plate amp on the back? Considering the PR will be tuned to 30hz, total box F3 is 30hz, and I'm only interested in 30-50hz range is it logical to place the PR in front since 75% or so of my usable range will be coming from it?
Here's a picture to put it into perspective...

It's exactly to scale, +/- 0.001mm

except for the dust cap, could not find it's size. Spikes of course could me mounted on something to give about 2" floor clearance if driver is going to be down firing. The box is exactly 12x12x12 internal + compensating for 3/4" MDF, didn't factor in displacement from bracing or driver yet, but that's minor. So how would you folks recommend arranging this stuff?

 

[Dustin Haug]

Depending on the model of PR they should have weights (washers or something) or maybe clay. Adire and Stryke sell some nice ones you may want to consider those. I haven't seen the PE ones yet. I think the arrangement you mentioned should work fine. That's how several commercial subs are made. I think it looks awesome to have 3 PR's and a driver, one diaphram per side of the box (minus top and bottom). But you can't really do that if you're going to use a plate amp mounted to the box.
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My DIY sub page

 

[Dustin Haug]

Forgot to mention, nice CAD drawing. What did you use to do that?
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My DIY sub page

 

[Mike Lenthol]

Just Adobe Illustrator. Simple 2D, but it's enough to see how the results would look. By the way is there any software that would plot the output response from driver and port separately? Would be interesting to see if putting it on the bottom is ok.

 

[Greg Monfort]

Forget the PE PRs for sub duty. WRT downfiring, do it only if the manufacturer lists it as an option, otherwise the only decent option is to mount the PR opposite the driver. If you don't want the amp on the side, you can always make a separate complementary box for it.
GM
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Loud is beautiful, if it's clean

 

[Mike Lenthol]

Is placing the PR on the opposite side absolutely necessary? I always figured that to be one of those 'perfectionist' things. Sort of like upgrading a 10 gauge wire to 8 gauge I'd be willing to sacrifice a little function over form.

 

[Arnold P]

For the Peerless XLs10 the price in Dutch Guilders is 350,- (should be about 160 USD)
You can have a look at the complete design (speaker, radiator + power plate amp 200W) at the site if the German speaker company "Intertechnik"
The sub goes down to f3 18,5Hz (within linear range)

 

[Greg Monfort]

No, it's not absolutely necessary, it's just the best compromise WRT vibration cancellation. For sure it can't be on the top or bottom, due to its extremely low compliance.
If you want to please a female, place them both on the same baffle, and have her sit on it while it's playing some LF near Fb at high volume.

GM
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Loud is beautiful, if it's clean