SA-8 Power vs. Box Size

[sundownz 197]

Box size has alot to do with mechanical power handling. If you are going to be pushing your woofer beyond it's rated RMS power you need to be very mindful of this fact and put the woofer in no larger than the minimum suggested enclosure for music program.

We design our woofers for very small enclosures and power ratings are there for a reason -- you can continue to push a driver like the SA-8 beyond RMS power and it will not be stressed whatsoever thermally by the time you can cause mechanical issues. The motor, especially on the SA-8, is VERY strong -- being an 8" driver there is limited mechanical throw available. The driver retains high motor force all the way up to the point where you can start breaking it.

In any event... based on my testing so far you can expect something like the following on mechanical power handling vs. ported box size on the SA-8 :

1.25 cubic feet = 300 watts

1.00 cubic feet = 400 watts

0.80 cubic feet = ~450-500 watts

0.60 cubic feet = ~500-600 watts

You may ALSO need a subsonic filter depending on box tuning. The rated RMS power is 400 watts RMS -- if you push past that you are voiding warranty coverage. We are bringing in re-cone parts and they can be fixed, though, for those of you who like to push things. If you have any doubts about your ability to monitor your listening habits just stick to the 0.60 recommendation.

To re-iterate... they are not fragile. I have ton ALOT of testing on them with enormous amounts of power -- the above considers full bandwidth music program that can drop to very low frequencies and is a safe suggestion.

If you are an SPL competitor then you probably already know this and these suggestions don't really apply for burps @ tuning. We have put in excess of 600% of RMS power on them for SPL burps.

[Soapbox 7]

Thanks for the info. With widely varying applications this helps narrow down the field of options.

[quiet 0]

nice thats a real good guide, more manufactures should give recommendation like this. Especially for a entry level speaker where inexperienced users will likely need the help.

[sundownz 197]

A little revision here...

If you are going to beat the daylights out of your sub *constantly* do not, for any reason, use more than 0.5-0.6 cubes for it at any power level.

The original recommendations are assuming that some care is taken to monitor mechanical stress of the driver.

[mrbojang 8]

What about for the sa-10's?

[j-roadtatts 1,129]

Good info Jacob.

[Kanaworm$ 292]

Pin this as this is very informative!

[sundownz 197]

What about for the sa-10's?

All of our subs are designed around small boxes -- the SA-12s like about 1.5 cube the 10s more like 1 cube ported. Cut either one in half +/- 25% for sealed.

[sundownz 197]

I am going to revise my suggestions a bit... honestly 0.5 - 0.7 should be used for pretty much ANY power level.

Based on more real world testing with customers -- a heavily abused SA-8 can mechanically damage itself in the larger boxes even on lower power.

[klee7013 10]

great information was just thinking about adding a port to my sealed enclosure

is that before or after displacement-

i got 3 sa8s in a sealed box with volume before displacement 1.7 cubes maybe 1.75 hard to get exact

i want to go ported now

can i add a aero port or 2 to that and be good for internal volume or should i got up to about 2 cubes for total box volume then add a port(s)

running off a sae1200

thanks

kevin

Love my sa8s now i want to make them ported so people can say wtf those are 8s even more

Edited August 6, 2010 by klee7013

[PHATBOi 38]

Thanks for the info Jacob! This works right into my plans as I have only ~2.5^3 after displacements and am really interested in using 4 of these bad boys in my next setup. Now all I have to do is wait on the funds, lol. Come on income tax !

[ludeman 86]

What's the displacement for the sa-8?

[klee7013 10]

about .10 cubic feet give or take-- about 95% positive

[SPL_Man 20]

nice info but u shud also give the recommended square inches of port per cuft too

[Virindok 0]

Well I just got my sa-8 and threw it in a .6 cube ported box and I'm giving it around 500 watts.... and I feel like it could sound so much better.

I may build a new box and try to tune it lower - but that will mean a bigger box so I'll have to set the power appropriately. Anyone have recommended box specs?

What would you recommend tuning the box to? I want clean lows - I care more about SQ than SPL. Obviously an 8" woofer isn't going to be a low end monster but I expected a lot more after reading everyones reviews and seeing all the videos.

Thanks in advance.

[Kanaworm$ 292]

Well I just got my sa-8 and threw it in a .6 cube ported box and I'm giving it around 500 watts.... and I feel like it could sound so much better.

I may build a new box and try to tune it lower - but that will mean a bigger box so I'll have to set the power appropriately. Anyone have recommended box specs?

What would you recommend tuning the box to? I want clean lows - I care more about SQ than SPL. Obviously an 8" woofer isn't going to be a low end monster but I expected a lot more after reading everyones reviews and seeing all the videos.

Thanks in advance.

Bump up the box to 1.1ft^3 and tune to 32-33hz!

[stevemead08 752]

Well I just got my sa-8 and threw it in a .6 cube ported box and I'm giving it around 500 watts.... and I feel like it could sound so much better.

I may build a new box and try to tune it lower - but that will mean a bigger box so I'll have to set the power appropriately. Anyone have recommended box specs?

What would you recommend tuning the box to? I want clean lows - I care more about SQ than SPL. Obviously an 8" woofer isn't going to be a low end monster but I expected a lot more after reading everyones reviews and seeing all the videos.

Thanks in advance.

Maybe your amp/HU settings are not right. i played with just one in a small ported box @33hz off a sax125.2 and it gets impressively loud and low for a single 8" sub

[sundownz 197]

I do not really suggest going too big on the box... it is all about your expectations -- while they are awesome woofers an 8" sub only displaces so much air.

[Virindok 0]

Thanks for the replies. Now that they're properly eq'd and positioned in my car - they sound great. Now I need to fit 2 more into my little hatchback.... =p

If/when I do get 1 or 2 more, I'll be upgrading my amp and building a new box that will be tuned a lot lower.

Edited September 22, 2010 by Virindok

[hrtbrk1 2]

can two be ran in a 1cuft box tuned to 32 hz?

[sundownz 197]

can two be ran in a 1cuft box tuned to 32 hz?

Yep.

[hrtbrk1 2]

thank you kind sir

[oldsch00lf00l 0]

nice info but u shud also give the recommended square inches of port per cuft too

X2, I was wondering if Jacob had a specific targeted port area in mind for the SA-8s.

I know it is really tough to get a decent port size for one subwoofer in .6 cubic feet net because I ended up building a super skinny port to have my wife's True Bass Ultra 8 tuned to 32 Hz. In her case it was not so bad to go with a .75" wide x 8.5" high x 18" long port since the sub is in the trunk of her car. In my case, I'd likely hear the port noise because I am trying to pull off a sealed, direct fire design with the SA-8s that I ordered.