# 8" normal or 10" shallow sub - what's better?



## Boson21 (Aug 4, 2012)

Here's the question(s);

*What's your thoughts for obtaining best results with a small sealed enclosure - 8" conventional subs or 10" shallow mounts? *

Is it better to drop the cone size for a more conventional driver with better xMAX, or to achieve good SPL / bass extension is it all about getting as much surface area as you can?? - It would also be good to know what are considered to be the pro's / con's to both approaches, and are there any gotcha's or tips people would like to share?

I'm trying to keep this a bit non-specific in terms of drivers (I have a thread running already to create a current list of 10" subs with a mounting depth of less than 5" - but didn't want to pollute it or take it off track with this debate, and hence a different post).

Happy for this to be focused on general thoughts / experiences to keep it useful to a wider / future audience, but I know 'best' is subjective and depends on what you are trying to achieve so for any specific thoughts here is the key criteria in my specific requirement;


Small sealed enclose (18l)
Looking for max bass extension (to support existing mid-bass drivers that go to about 55hz well)
Decent SPL when driven at relative low power (about 180W to 200W RMS)

Like I say, any comment doesn't have to relate to this criteria, but it's there in case more info to work with is needed...all input much appreciated - thanks


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## Chaos (Oct 27, 2005)

All things being equal, generally the larger cone will be more capable of playing lower, louder and with less distortion. It is possible to make up some of the difference by trying to utilize a smaller cone with a much higher excursion capability, but you would also need more power to do it.

Of course, all things are not equal and the only way to know for sure is to compare different options directly whenever possible.


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## minbari (Mar 3, 2011)

it would depend on the 8" and 10". alot, if not most, shallow subs have crappy xmax. so if you have a 10" shallow with 8mm of xmax and an 8" with 15+mm of xmax, the 8" will take more power and sound better IMHO.

there are limited exceptions. I understand the alpine shallow have an xmax of about 17mm, so those might be a good suggestion.


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## Boson21 (Aug 4, 2012)

Indeed...

I happen to have a Rainbow Vanadium 8" in a box - supposed to quite an impressive driver and modelled in WINISD its response walks all over the slim subs. The Apline is where my hopes were initially pinned with the surface area and xMax as you note - but modelling the figures at least it is quite unimpressive in terms of bass extension / F3 and SPL (on paper the smaller Vanadium significantly outperforms the Alpine shallow 10" in extension and SPL - from what I have read it's SQ is good too).

This is what posed me to post, as everything I had to go on was calculated and what everyone's really interested in is how things actually sound  So I thought I'd canvass opinion to see if I was barking up the wrong tree, or is the calculations were likely to be a true representation of the difference sound wise...

To add complication to my specific predicament though the drawback with the Vanadium is it is dual 4 ohm VC. I have no amp specs as it is fibre MOST input / OE and they won't release (or the people I've spoken to don't understand) the info. The current OE driver is 10", single VC and measures 3.1 ohm at rest, so I have no idea if the amp could drive into the two VCs in parallel as that would be a little less than 2 ohm, in series we are looking at 6+ ohms (so assumedly reducing the power and so the cone excursion / SPL which defeats the object somewhat) and as the Vanadium is rated peak at 250W I can't really run it single VC for fear of cooking the coil! Anyway, enough of my specific issues with that driver as that wasn't what the post was about!

So from what you say minbari it is quite possible the WINISD plots are right that in all reality an 8" could provide 'better' response than a 10" under these circumstances / compromises...

Thanks for the input  big help to know I'm not going mad at least!


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## minbari (Mar 3, 2011)

Boson21 said:


> Indeed...
> 
> I happen to have a Rainbow Vanadium 8" in a box - supposed to quite an impressive driver and modelled in WINISD its response walks all over the slim subs. The Apline is where my hopes were initially pinned with the surface area and xMax as you note - *but modelling the figures at least it is quite unimpressive in terms of bass extension / F3 and SPL (on paper the smaller Vanadium significantly outperforms the Alpine shallow 10" in extension and SPL - from what I have read it's SQ is good too).*
> 
> .......................


complettey agree. model one of the pioneer shallow subs, lol. I dont know what it is about the shallow subs, but they just dont have the nice pretty freq res that a more typical sub does.

if you have the depth for a standard style 8", I would go with that. if you have no space and cant use anything but a shallow sub, then you are stuck with it 

how much power does the stock system give the sub? if it is around 100watts, then the rainbow will work fine. run 1 coil and short the other coil together. the other posibility is to get a mono amplifier with high level inputs that can drive a 2ohm load.

BTW a 4ohm speaker will ohm out to about 3.5ohms or so.


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## Boson21 (Aug 4, 2012)

even if I'm mad there's comfort in not being alone then  

Stock amp is reported at 200W RMS, hence my concern. I don't have the room for another amp really (was looking at a Clean-sweep on the O/P and then amping everything north of the OE unit but ruled this out as impractical). Was thinking about a heat-sinked 2 ohm resistivity in series with both coils in parallel but then figured that would likely be the same power/SPL wise as running the two 4 Ohms VCs in series anyway. Ultimately I think it will be risk the VC on the driver or accept lower OP (as the amp is made by Linn and I've been quoted £2000+ to replace by a dealer so I ain't got the bottle to jeopodise that without solid knowledge that it could drive into 2 ohm nominal!!).

8 inch sub it is I think, regardless of whether its the Vanadium or other...(but really like the way that Rainbow modelled) as I'm more convinced than ever that cone area isn't the be all...

Thanks again


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## minbari (Mar 3, 2011)

Boson21 said:


> even if I'm mad there's comfort in not being alone then
> 
> Stock amp is reported at 200W RMS, hence my concern. I don't have the room for another amp really (was looking at a Clean-sweep on the O/P and then amping everything north of the OE unit but ruled this out as impractical). *Was thinking about a heat-sinked 2 ohm resistivity in series with both coils in parallel but then figured that would likely be the same power/SPL wise as running the two 4 Ohms VCs in series anyway. U*ltimately I think it will be risk the VC on the driver or accept lower OP (as the amp is made by Linn and I've been quoted £2000+ to replace by a dealer so I ain't got the bottle to jeopodise that without solid knowledge that it could drive into 2 ohm nominal!!).


spot on! the resistor would get half the power and nicely heat the trunk, the sub would get half the power. no different than wiring it to 8ohms and much easier on the amplifier.


> 8 inch sub it is I think, regardless of whether its the Vanadium or other...(but really like the way that Rainbow modelled) as I'm more convinced than ever that cone area isn't the be all...
> 
> Thanks again


there are higher rated sub s that sound very nice. look into the TC sounds 8", JL 8w6, JL 8w7, DD 1508. those will all tkae the kind of power you have. just keep in mind that you want a SVC 4ohm or a DVC 2ohm.


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## Boson21 (Aug 4, 2012)

Thanks - I'll take a look at those...


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## [email protected] (Jun 12, 2008)

minbari said:


> spot on! the resistor would get half the power and nicely heat the trunk, the sub would get half the power. no different than wiring it to 8ohms and much easier on the amplifier.
> 
> there are higher rated sub s that sound very nice. look into the TC sounds 8", JL 8w6, JL 8w7, DD 1508. those will all tkae the kind of power you have. just keep in mind that you want a SVC 4ohm or a DVC 2ohm.


You need 3 8w6's to make a 4 ohm load. And the 8w7 only comes in a single 3 ohm coil.


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## minbari (Mar 3, 2011)

BeatsDownLow said:


> You need 3 8w6's to make a 4 ohm load. And the 8w7 only comes in a single 3 ohm coil.


thanks, I didnt bother to look up the coils.


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## its_bacon12 (Aug 16, 2007)

The Dayton shallow subs are pretty nice (the 10" works in .3 sealed - one on the way to me). I place a much greater preference on a greater surface area subwoofer stressing less.

Other than that, Peerless XLS shallow 10", TB shallow 10", ED SQ10, Illusion audio 10" on ebay, etc..


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## Hillbilly SQ (Jan 26, 2007)

I saw the dd1508 mentioned. I tried one in a ported box from a shop in Lousiana at a g2g and the 400rms I had barely tickled it. They really need closer to a kw to really get going according to the people that are running them.


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## Boson21 (Aug 4, 2012)

That's a lot more power than I have without adding a Clean-sweep and all new amplification (forget the cost for a minute, the space is the bigger issue with that approach in my specific case as I've already considered).

I'll take a look at those other shallows - thank you...

Thinking about it, maybe that's a pro for the 8" in certain circumstances, they generally need less to drive them..? I was really sold on the 10" approach and it was really a case of which one, but now I'm really on the fence - need to pick a side soon as feeling the need to spend and get this sorted 

Thanks for all the comments / input thus far - much appreciated...


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