Just got these in... designed them based on many requests for a really good sealed box 8" woofer. Power rating is pending testing but mechanically I designed them around 300 watts or so (half the spiders of the SA-8 v.2) -- we'll do our thermal cycle to determine the official rating. As is typical with our products the rating giving will be a "worst case" rating and many people will have no problem running a bit extra.

We built upon our newly tooled platform from the SA-8 v.2 so it shares many of the advantages of that platform from the get-go.

These feature an under-hung coil with predicted linear x-max of ~14.5mm one-way by 70% BL method using an 8-layer copper 2" coil with 1/2" of winding width.

The total depth for mounting is right at 4.75" measured,

I will be measuring actual T/S on them later on today after some break-in time. Pricing is also pending final costs from our parts suppliers.

On to the photos :

* E8 v.2 then SD-2 8" then SA-8 v.2

* For this design I used drilling in the basket as opposed to the vent ring to save depth.

* Solid pole like the other SD-2 woofers so there is no need to leave room to breathe behind them.

* Same spider as the SA-8 v.2 but only one layer (top layer)

you always got something in the works

I am happy with the mechanical behavior and observed thermal behavior so far playing them in free-air -- specs measured before break-in indicate I MAY have to make some small tweaks to it with the mass and compliance but it's about 90% there.

And you said these will be more suited towards sealed boxes than the E-8's?

Does that apply to the SD series vs the E series as a whole?

So there designed for sealed, but will they still hold there own in a ported application?

So there designed for sealed, but will they still hold there own in a ported application?

There is no inherent reason you can not port them; but they are being tailored to sealed boxes.

And you said these will be more suited towards sealed boxes than the E-8's?

Does that apply to the SD series vs the E series as a whole?

Not really in the bigger sizes.

Jacob, seems like a nice middle size between the e's nd the sa's. What volume will the 8s work in sealed? Thank you, JPS

I just installed the pair in my car (TWO SUBS) in 0.5 ft^3 sealed and took a nice listen... I am really quite impressed. Brandon, Thomas, and I all agreed that per box volume you will be pretty hard pressed to get this combination of output, bottom end, and sound quality. I need to get a little video... it was shaking my visors, rear view mirror, etc... obviously nothing insane but the output did surprise all of us.

Currently on my 200.4 bridged @ 1 ohm (turned way down) -- I wired it this way as I plan to test the new 1500D v.3 in my car soon as well as the new 125.4 on the fronts.

The only 8" out there that I know of that will out-perform these sealed is a JL Audio 8W7 (which is a GREAT woofer... my favorite JL product period)... but it does call for a MUCH bigger box to do it (0.875 ft^3). The JL has more x-max (19mm vs 14.5mm on ours) and models out with a lower F3 point but at the expense of about 3x the cost and over 2" more mounting depth.

If you put three SD-2 8s in the same 0.875 ft^2 as one 8W7 you would come out about the same price and end up with more output -- just depends on what you can fit as far as face area for woofers.

Okay here it is :

I am really pleased with these little guys

That's pretty crazy Jake! Honestly gonna consider a few of these for the mini when i get it.

I am making one small change for production -- the pole extension is growing by about 1/2" -- I was able to shoot the coil completely out of the gap and scrape the winding on the top plate with about 3x rated power

With the extension pushed out that will become impossible at any power level -- as it would take over 30mm one-way to completely jump over the pole with the taller extension.

Had to push back this production run a bit to fit a few more things in; but I'd expect to see it in November to December.

Specs on the unit played for extended period in my car :

Re : 6.03 ohms (series)

Fs : 45.2 Hz

Qes : 0.63

Qms : 7.31

Qts : 0.58

Le : 6.26 mH

Sd : 30.68 in^2

Vas : 7.74 L

BL : 15.55 NA

Mms : 89 g

Cms : 138 uM/N

Sens 1w/1m : 82.29 dB

Box modelling programs will call for a bit over 0.5 each sealed -- I ran these in 0.25 each and they sound great. Being a very linear driver over stroke your Qtc at higher levels of travel would be about the same as a driver with a lower at-rest Qtc and non-linear CMS and BL curves.

In any event -- the specs are within a VERY small margin of my original test-bench break-in process on them... so the parts will show very little fatigue and change over time after initial break-in. Not a surprise as they were all designed around the much more powerful SA-8 v.2

They would have no issue with a ported box but I feel like their main advantage is performing better sealed than an SA-8 v.2

Also will be doing Klippel testing on this at some point as I've done with the SA-8 v.2 and SA-12 models.

PS: I notice I haven't mentioned one of the details yet... the former is an alloy material similar to brass with a spiral cut to help reduce eddy currents compared to a standard aluminum former.

Very interesting... Why the alloy former? Al just seems like such a logical/practical choice you must have some supreme motivation... Hella curious now

And did you ultimately fiddle with the mass/compliance? Or I guess I should ask is the qts, Vas, and fs listed above before or after any potential changes or is that the final product?

After listening tests I decided to leave them alone as-is other than a few minor motor mods for production (won't change T/S significantly).

As these are not thermal-monster woofers I was afforded bit more flexibility with the former material (aluminum is typically the choice thermally) -- I didn't want to go to a material with a significantly different amount of thermal expansion compared to the winding material (SS or Ti) nor did I want to use a polymer material as I did want to retain a fair amount of thermal conductivity in the former (despite it's conservative ratings I'd be kidding myself if I thought everyone would run exactly RMS)... so I went with an alloy which has about 80% of the thermal capacity of aluminum and also some natural reduction in eddy currents -- then I added a spiral cut to it to further drop down eddy currents beyond the material change itself. I feel like it's a great compromise for a woofer of this type

Here is the coil itself :

It is no worse for wear after all my abuse thermally -- but I did physically damage it as mentioned above. This possibility is resolved by the taller pole extension

I'm looking at putting two 10s in a down fire box under a f150s seat. I only have 1 1/4" clearance between baffle and floor board. Will I have enough clearance? Hard to tell the height of surround in the pics.

Correct me if I'm wrong, but what I captured from the video, the displacement of the subs are roughly .08 ea.... is that correct? I'm about to buy 2 of these for a center console box in my Hardbody. Trying to figure out some numbers. Let me know, thanks....and a great looking sub btw. Exactly what I was searching for for my regular cab Hardbody.

Correct me if I'm wrong, but what I captured from the video, the displacement of the subs are roughly .08 ea.... is that correct? I'm about to buy 2 of these for a center console box in my Hardbody. Trying to figure out some numbers. Let me know, thanks....and a great looking sub btw. Exactly what I was searching for for my regular cab Hardbody.

yes that is a good estimate.

I'm looking at putting two 10s in a down fire box under a f150s seat. I only have 1 1/4" clearance between baffle and floor board. Will I have enough clearance? Hard to tell the height of surround in the pics.

 i would also like to know this,

 

 and also what is the diameter of the motor it is above or below 6 inchs ?