SEOS12/2512 Build

Final Outcome


Here are the details for the final build and photos of the finished products.


Thanks to all that helped me with the build. I could not have done it without you.


A word to fellow noobs: you can do it.


I would recommend getting Erich's kits/flat packs. This build is definitely doable without, but why do through the hassle if Erich has already put it together for you. Kit link: http://www.diysoundgroup.com/plastic-seos-12/seos-speaker-kits/seos-deltalite-kit.html


As far as opinion on the final outcome, phenominal. Night and Day difference from my Paradigms. My goal was to get "bigger and better detail" and boy did I get them. They take everything I throw at them without breaking a sweat. The detail is there. The "bigness" is there. Also, something that is hard to describe, but it all tied together seamlessly. You soon forget about the speakers and just enjoy a seamless stage of music/sound.


Hats of to BWaslo for a fabulous design. Thank you, Bill!!


Last, LTD02 summed up this design far better than I could:

+1...the seos12/dna360/2512/bwaslo crossover network is a really great bang for the buck performer. heck there are even flat packs available for that build from erich's diysoundgroup. speakers of this caliber with three famous little letters in their logo have sold for $1500-$2000 each, so diy it and get far more performance than the average guy can afford to. put the money saved into the subs and the screen and enjoy.

Drivers

• Waveguide. SEOS12
• Compression Driver. Denovo DNA-360
• Woofer. Eminence 2512

Design Source: http://www.diysoundgroup.com/forum/index.php?topic=9.0


Part Sources: DIY Sound Group and Parts Express

Final Product [excuse the dust prints...]


Final Box Layout


Box Part


Cut List. Using 1/2 MDF Boards


Crossover-Old. Final Board with Tweeter lead problem


Cossover-Fixed. I had to move the positive tweeter lead. Sorry, I forgot to take a full shot of the fixed board.

Sealed vs Ported


Given I am building this for HT, I've always assumed I'd be porting the LCRs and subs, but now I don't know. After going through numerous (countless?) DIY Speaker and DIY Sub threads, I started picking up a trend of warnings about porting. Basically, it's fairly easy to design but hard to implement. This is both on a box level and then trying to blend the mains with a sub. Thoughts?


I thought I'd go the "easy/safe route" and go sealed all around, until I played around in WinISD. Am I reading this correct? I understood that the much lower end was extended vs sealed, but that a sub(s) would offset that. But looking at the below, it looks like there is a big gap before sub crossover (80 hz). I realize that the crossover will smooth some of the gap (i.e., blend up from 80hz), but 3.5db seems like a lot to overcome. Seems like porting may need to be added back to plans. Thoughts?




So, if I go ported, what should I tune the box at? WinISD set it at ~45hz. Is that a could target? What about future blending with the sub(s).


Thanks!!

you have chosen good components so are well on your way to a good build.


if you plan to crossover from the mains to the sub at 80hz, then the sealed will work great.


technically your receiver will apply a 2nd order high pass on the mains and a 4th order low pass on the subs.


in order to get them to play the same through the crossover point, both sources need to be down 6db.


a 4th order will be down 6db. a 2nd order will only be down down 3db. so where does the other -3db come from? the natural rolloff of the sealed mains.


so when designing a thx style main (they call them sattelites), you want to use a sealed enclosure that has a -3db point of 80hz. guess what. that is exactly what you have plopped yourself into. nice planning!



Quote:
Originally Posted by LTD02  /t/1417294/seos12-2512-build#post_22162939


you have chosen good components so are well on your way to a good build.

if you plan to crossover from the mains to the sub at 80hz, then the sealed will work great.

technically your receiver will apply a 2nd order high pass on the mains and a 4th order low pass on the subs.

in order to get them to play the same through the crossover point, both sources need to be down 6db.

a 4th order will be down 6db. a 2nd order will only be down down 3db. so where does the other -3db come from? the natural rolloff of the sealed mains.

so when designing a thx style main (they call them sattelites), you want to use a sealed enclosure that has a -3db point of 80hz. guess what. that is exactly what you have plopped yourself into. nice planning!

Click to expand...

Thanks, LTD02


I guess I did absorb a little (80hz) from all my thread readings.


Seriously, I've tracked a lot of your post through DIY Speaker and DIY Sub threads. Always informative and helpful. Thank you.


To that note, as I start planning the sub(s) build, stay sealed? I'm assuming that twin 15" subs should have still have quite a low end kick versus my current since 12" ported (PDR12). Also, from an "ease of use" perspective, Erich's flat packs would make this "stupid easy".


Thoughts?



Quote:
Originally Posted by mobeer4don  /t/1417294/seos12-2512-build#post_22163024


No doubt sealed will work. If you go ported, you can move the crossover to the sub to say 60 Hz and use more of the 2512's capability. I like the idea of letting the mains deliver a little more punch/slam (whatever you want to call it) when they are capable of doing it....and the the 2512 is quite capable if you don't try to push it too low. You would need to dig a little deeper into the power/excursion/tuning parts of the model to see what you can (or can't) take advantage of.

I'll admit I'm biased for this type of setup since I'm running ported JBL 2226's for mains crossed to the sub at 60 Hz. I'll also be following closely since I have a pair of the 2510 that should make for some nice surrounds.

Click to expand...

While I like the thought of pushing the mains, since this is my first build I think sealed will be a safer approach all around. There is always the next build...


To that, I've been eying the 2510 also for the surround. I think the 2510 mated with the SEOS12 would do well. Below is my "model". It is from stgdz' build: http://www.avsforum.com/t/1265019/stgdzs-qscinema-build#post_18951194




Also, BWaslo designed an interesting center channel called Malcolm: http://www.diysoundgroup.com/forum/index.php?topic=11.0 . The lower profile could be a better fit on walls.



Quote:
Originally Posted by Java  /t/1417294/seos12-2512-build#post_22162888

Sealed vs Ported

Click to expand...

I chose the Delta-12A for the cost savings (the $140 saved can go into the next build) and efficiency. I wanted small boxes for portability and modeled them accordingly.


1.7 cu. ft. modeled at 150 watts with 100Hz 4th order HP, the 12A ported bests the 2512 sealed by about 2 db. It also edges the 2512 ported, but not by as much from 100-200 Hz. Above 200 Hz the 2 db lead remains. Be careful with these drivers, their Xmax and Xlim can be reached easily without filters. At first I was leaning toward very small sealed, but then the Fsc comes into play and I'm not sure how close to the passband it can be.


I really think this is splitting hairs, and other factors are likely more significant for overall SQ.

Thanks for all the input.


My SEOS12's and DNA-360's have shipped.


Now I have my finger on the trigger to order 3x 2512's, but one thing is bugging me. What about the surrounds? I know I need match the "voice" of the mains to surrounds, but is the "voice" defined by the tweeter or woofer? Or both?


The reason for my question is that BWaslo's 10" design is with a Designer 10 not a 2510.


Ideally, BWaslo will say that the 2510 is interchangeable with that XO design or will create one for the 2510. If not, what would be the impact of going with a Designer 10 for surrounds? I was planning on using the SEOS12/DNA-350, so that should match the voice of mains well. But what about the woofer? There is also a good 7db difference in sensitivity. Will that be an issue?


If this is a show stopper on the surrounds, I may need to go the Designer 12 route...



Quote:
Originally Posted by mayhem13  /t/1417294/seos12-2512-build#post_22166420


No need To timbre match surrounds. The 2512 sealed is the right choice for the mains. I've mocked mine in 2cuft sealed each and I plan on not high passing them at all, rather letting them overlapp the subwoofers as per Geddes.

Wanna build some budget saving subs?.....check out the Infinity reference series 1260's or 1262's if you want to do 2 drivers per box. Great power handling, excursion and extension at a price that's hard to beat.

Click to expand...

Thanks, Mayhem. I researched a bit on the Geddeis' overlap and couldn't find anything. Could you please point me to the concept?


On the Infinities, huge deal: http://www.amazon.com/Infinity-Reference-1260w-1200-watt-High-Performance/dp/B0028AVGEO/ref=sr_1_1?ie=UTF8&qid=1340670071&sr=8-1&keywords=Infinity+reference+series+1260 . Thanks for heads up.


Did you build them as a dual? Opposing?

Update. Ordered 3x 2512's, so the driver chapter is done.


Now it's time to design the box. I'm on a steep learning curve with all the software available, so any input is greatly appreciated.


First, I need to determine the volume. Mayhem, you are using 2.0 cuft, right? That looks what I will use too, but wanted to verify assumptions.


The goal is to get Qtc close to .707 for a flat response, right? If I read below correct, a 2.0 cuft box nails that.




Using the box calculator at DIYAudioandVideo , and my goal to be about 30" tall and keeping the baffle at 15" wide (per BWaslo), I get the below options. I'm guessing that the first box (28h x 15w x 12d) is the better bet than the 2nd option (30h x 15w x 10d). The second seem to thin. What is the min "clearance" for drivers? Last, are folks using any floor spikes? I have thick padded carpet over concrete. These spikes add 1 1/2", so that get's me close to my desired 30" with option 1.


Option 1



Option 2