2012 Frame / Cone -- First Built Woofer

Few more photos this morning compared to other Z model woofers :

http://www.sundownaudio.com/misc/pro...t/CIMG6655.JPG

http://www.sundownaudio.com/misc/pro...t/CIMG6653.JPG

http://www.sundownaudio.com/misc/pro...t/CIMG6654.JPG

http://www.sundownaudio.com/misc/pro...t/CIMG6656.JPG

http://www.sundownaudio.com/misc/pro...t/CIMG6657.JPG

http://www.sundownaudio.com/misc/pro...t/CIMG6658.JPG

Quote:

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Originally Posted by sundownz

I am kicking myself a bit for getting crazy last night with it, haha... what I did was push it hard enough to exit the coil completely from the gap by a large amount -- the 12" frame supports 50mm of one-way travel not counting frame thickness... 59mm with frame thickness... and 71mm with vent spacer thickness added -- minus 8mm for triple joint ring so we can go 63mm one-way before bottoming the ring... and we have 62.5mm in the motor... so I had it up around 60mm one-way (which is actually 5mm PAST surround linearity)... which makes the coil about 1/2" past the gap *laughs*

So when it came back down it knicked the top plate and knocked loose 1/2 of one voice coil (the coil is an 8-layer bifilar which is wound as a quad; so you can knock out 1/2 of a coil by breaking one wire) and this wire is rubbing on the top plate now making that metallic sound (I can see the loose wire through the vent spacer -- WOOPS!!!).

Either way I have some ideas to minimize that possibility; although, I must admit, I was being totally careless with it to do that!

Needless to say it was pretty crazy and just me being too happy with my new toy

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http://www.sundownaudio.com/misc/pro...uilt/woops.jpg

Here is the wire I knocked loose -- you can see it through the vent. The piece hanging off is the part after the connection is cut so I can still play the driver (eg: not shorting out on the motor).

Coils of this type have four windings -- I broke just one so I am running on "one and a half" coils in the video.

I have noted some doubt on whether all of these new parts will be of major benefit (not in this thread, of course, but I do see alot of things around the internet) -- what I say to that is; stay tuned for the results ! :)

Quote:

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Originally Posted by sundownz

I have noted some doubt on whether all of these new parts will be of major benefit (not in this thread, of course, but I do see alot of things around the internet) -- what I say to that is; stay tuned for the results ! :)

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Definitely will be!

Despite the damaged coil I was able to pull specs then estimate where they would rest with a fully functional coil (as I have data from the 10" model to fill in the blanks that are not size dependent) -- 12" D1 model.

Re : 1.65 series
Fs : ~25.75 Hz
Qes : ~0.296
Qms : ~4.16
Qts : ~0.276
Le : ~1.8 mH
Sd : 457 cm^2
BL : ~17.23
Mms : 329 g
Cms : 115 uM/N
Sens : ~85.01 dB
BL^2/ RE : ~180 (D1 coils are usually a hair higher than D2; but for estimation purposes I used the same as the D2 coil)

So these are estimated based on the known specs and specs from the 10" D2 -- gives us a good idea.

As I mentioned in the 10" thread I may need to add more stiffness into the surround to get the specs to lay where I want them -- realistically I'd like to see the Fs into the low to mid 30s on the stock format driver. You will note that the CMS is higher than the 10" model as the spiders and surrounds get a bit softer as their size increases; thus we have an even LOWER Q figure on a 12" than we do on a 10" model -- on the Z v.3 the surrounds compensated by also getting stiffer as size increased (the 18" Z v.3surround is very stiff) -- so I'll have to do the same on the new surrounds.

So more testing will be getting done with some surround tweaks :)

I'm really looking forward to seeing the new 15". I'm hoping to do a build with two of the 15's and a 5k in the spring. Any better ETA on the release? Count me in for the pre-order btw.

These are some massive subs. Can't wait until pre-order gets here!

I like the beer just chillin in the very first picture! ;)