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SEOS-12/TD12M/DNA-360 Build - Page 2

post #31 of 91
Nice work RB.

I wouldn't worry too much about baffle step compensation with speakers this wide unless you place them well into the room and away from every boundary including floor and ceiling. The theoretical BS corner is about 380hz for a 12" wide speaker, but the theoretical corner is not indicative of what really happens. The theoretical BS calculation overestimates the frequency and severity in real applications. Even away from all boundaries, I'd guess closer to 300hz and 2-3db.

Ultimately, most people won't place their 2-way horns away from all boundaries and instead are somewhere in the range of half or quarter space in the bass range. IMO, this is a strength of larger 2-way horns like this as they blend well in small rooms as the room transitions to the modal region and the system hands off to bass duties to subwoofers. Integrating a narrow baffle speaker in a typical home theater room is much tougher.
post #32 of 91
Thread Starter 
Thank you, Max. And also, thank you for all the advice and information during our exchanges via pm. It was those conversations that provided me the mountains of possibilities and resources that spurred my tiny portion of work towards this project. It's really cool to see the major players post to this thread and to truly experience the recipiency of the collective work going on here.

Yes, once we're in the modal region those frequencies are, as Bill expressed, an issue of room eq. I mean, A 440Hz has a wavelength of ~30", and depending on placement in the room, such a rise would be eq'd as we move from the half space simulation to real-world quarter space.

My next build may need a bit of attenuation in those regions because of baffle size, however. The baffle shall be 13" using the td10m and seos-10 for surround use. 1kHz has a wavelength of ~13" and the recommended minimum crossover point for the seos-10 is 1.4kHz, so I'm not sure how to address the rise in response within that region? The port tuning is 60Hz and F3 ~80Hz. Since I can't use 5 identical speakers, I need to get this enclosure the size it is, 0.5 cu.ft plus waveguide section.
post #33 of 91
RB-

Where will you place these surrounds? On-wall and possibly near the ceiling wall junction or in a corner? If so, you should not have to worry about BSC. Up against a wall and you would have at most .5-1db of drop from about 1khz to 500khz and even that is unlikely. Beyond that you will most likely sit slightly off-axis causing this to be fairly moot. Even if you pulled this speaker out 3-4ft into the room, the effect would be small and could be counteracted by listening off-axis slightly.

Ultimately BSC is just a function of directivity over the entire frequency spectrum. One of the big advantages of the wider controlled-constant directivity horn speaker is that you don't have the BSC mess. I prefer placing a large 2-way horn in a corner or up against a wall.

Here is a good explanation from Parham: http://audioroundtable.com/forum/index.php?t=msg&th=12366
post #34 of 91
Thread Starter 
Excellent. Thanks for the link and after rereading your post I understand why bsc wouldn't be recommended for a 13" baffle and controlled directivity speaker. I like how Wayne summarizes those short essays, but I see how you are both saying the same thing. Simply put, bsc would only serve to attenuate frequencies that are already at the upper end of the LF modal region. Room eq and additional subwoofers to smooth room modes makes more sense.

The surrounds are on stands, sides of speakers are 3" to the back wall, LP is against the back wall, speakers are 3 feet from side walls.

Bill, I downloaded your tweeter zma/frd and woofer zma/frd files and loaded them into PCD to play/practice with. Not trying to reverse engineer your design or anything, just peering through the keyhole of the deep space-like chasm of crossover design. tongue.gif Following Jeff's user guide pdf, I can see how the shaping begins to trace the response as filter values are applied, that's interesting. I'm unsure what the driver xyz offsets are, so I was unable to input those. I was trying to replicate the session by inputting the values per your schematic to observe the transfer function target data, but I fail...big time. That's ok though, still learning. My simulated woofer response looked like two 100db spikes at 2kHz. lol Do you happen to have the PCD session file that you could share Bill?

Edit to say duh. rolleyes.gifTweeter axis: 22.5 horizontal (x), 0 degrees vertical (y), Z axis -48.5mm. Woofer axis: 22.5 horizontal (x), 0 degrees vertical (y), Z axis -42.2mm. Woofer + Tweeter system response looking much better after that!

Now to select the response shape. Both woofer and tweeter are 2nd order, right?

Thanks!
post #35 of 91
so you "upgraded" from the org parts hows that working for you,?

they look nice, may i ask in a HT setup wont you be missing out, vs a tweeter - mid - bass setup? just asking to gain more understanding. and how do the tweeter in this preform;) thanks
post #36 of 91
Thread Starter 
Thanks simple100. The only thing different on the crossover is the L3 inductor with lower DC resistance, perhaps that is the upgrade you're referring to? I may swap out the R2 resistor at some point just to play, but overall, I'm extremely pleased with the HF performance of the DNA-360.

As far as the three-way, that is exactly what I upgraded from and even then I was crossing to co-located subs to handle LF. The SEOS two-way enclosure I designed keeps the mid driver doing what it was designed for, mid frequencies. It can be tuned lower, but honestly, there is no need when the crossover point is 80Hz and the system is purpose built as a "THX" style main. I listen to music 80%, but also wanted a system that could handle movie soundtracks. These are capable of both, but you've got to run them with subs. Hope that helps.
post #37 of 91
Robot,

How is the setup? Still impressed and have you made any changes? I may be following your lead on this build. Are you using a center?
post #38 of 91
Thread Starter 
Hey pgwalsh,

They are really nice. I've listened to them 1-2 hours every day for a month, all kinds of sacd's and dvd-a (Aimee Mann, Steely Dan- Gaucho, Beck - Sea Change, Pink Floyd DSOTM and WYWH, Halie Loren "My Rainbow Race" (CD), Chet Baker, Miles Davis, Misha Mengelberg, Eric Dolphy) and I am still impressed in how detailed they are, effortless and transparent. They can also expose recordings that aren't so favorable and have made me scramble to find a high resolution alternative. I've got the pair ten feet apart, toed in past lp and sitting on top of each sub. They're sitting 18" high with the waveguide at ear level. I calibrated them on day one and haven’t felt the need to touch them.

Not using a center yet, but I've got all the drivers and wood cut. I really wanted to experience phantom center for a while after reading both Parham and Waslo's experiences, they are not kidding...the sound is amazing. It's like floating inside a giant pair of headphones, but with tactile sound...(I use Sennheiser hd-650's). Anyway, I'll build and use the center eventually as they will go behind an AT screen at some point.

If you decide to build them I'll follow your thread for sure! I'd be more than happy to assist in any way I can. biggrin.gif
post #39 of 91
Quote:
Originally Posted by robotbunny View Post

I calibrated them on day one and haven’t felt the need to touch them.

How did you calibrate them?
post #40 of 91
Thread Starter 
I used the Auto Setup and Room EQ function of my AVR-3805. redface.gif Not ideal, but it's what I've got for now. I desperately needed to upgrade my speakers first and then I could move up the chain with better processing and amplification. I'm getting there, slowly but surely.
post #41 of 91
Fair enough smile.gif
Quote:
Originally Posted by robotbunny View Post

C2:DAYTON AUDIO DMPC-2.2 2.2UF 250V POLYPROPYLENE CAPACITOR

Thought I'd double-check the parts list against the schematic and I see that the schematic has 2.0 uF, not 2.2.

Is that what you used?

Bill, I presume I should order 2.0, right?
Edited by noah katz - 12/11/12 at 8:24pm
post #42 of 91
Very cool RB! I have recently had the DIY bug bite me again. I have started my sub build and am looking at the Seos too. Have you had much chance to compare them with anything else??
post #43 of 91
Thread Starter 
.
Quote:
Originally Posted by noah katz View Post

Fair enough smile.gif
Thought I'd double-check the parts list against the schematic and I see that the schematic has 2.0 uF, not 2.2.
Is that what you used?
Bill, I presume I should order 2.0, right?

Thanks Noah. I just went with the PE#'s...it's probably fine, but if some glaring truth about the differences comes up, it's an easy swap. Good catch.

Thanks chop. If you've got the diy bug, you're in the right place. I haven't done any comparisons in the same room, so my opinions would be purely subjective. I can say I've heard speakers that retail for many, many thousands more...and you may find some members here replacing high end systems with these. So far, I've spent $500 per speaker, so $1500 total for the front three plus two diy subs for $700 with amp. How much they cost and the pleasure I've had building them myself put aside, I've never heard anything like them...

Having said that, I want to hear bwaslo's Synergy!
post #44 of 91
Quote:
Originally Posted by robotbunny View Post

.
Thanks Noah. I just went with the PE#'s...it's probably fine, but if some glaring truth about the differences comes up, it's an easy swap. Good catch.
Thanks chop. If you've got the diy bug, you're in the right place. I haven't done any comparisons in the same room, so my opinions would be purely subjective. I can say I've heard speakers that retail for many, many thousands more...and you may find some members here replacing high end systems with these. So far, I've spent $500 per speaker, so $1500 total for the front three plus two diy subs for $700 with amp. How much they cost and the pleasure I've had building them myself put aside, I've never heard anything like them...
Having said that, I want to hear bwaslo's Synergy!

Thanks for the input. I am a firm believer in DIY too. It is the only way for me to afford most of my hobbies. I built my on motorcycle, work on my own cars, you name it. Just can't afford to do it anyother way. If I cna DIY the theater for a fraction of the cost, I'm in. As you said, half of the enjoyment is the "doing", and knowing when its done it was your work. Old school pride thing I guess.
post #45 of 91
Thread Starter 
Finally got my OmniMic V2! Edited the first post to show system measurement, short sine sweep, bass removed. So far I'm pleased with what I'm seeing, I'll need to eq my bass response though.
post #46 of 91
Is that in-room? looking pretty good, care to run another with the bass still in the mix but perhaps subs off?
post #47 of 91
Thread Starter 
Thanks. Ya, that's in room, kids are watching Ice Age at the moment...measurement soon. I measured earlier and I've got a dip right at my crossover frequency of 80hz, changing it to 100Hz improved response. I'll post later this afternoon.
post #48 of 91
Thread Starter 
Here is a sweep with subs off.

OmniMic V2 system measurement @ 1M (SEOS-12/TD12M/DNA-360), Track 12, Right Channel - Short Sine Sweep, No Subs.

With the subs on I get this dip from 70-80Hz. Need to EQ.

OmniMic V2 system measurement @ 1M (SEOS-12/TD12M/DNA-360), Track 12, Right Channel - Short Sine Sweep, Subs On.
post #49 of 91
Try reversing polarity on the subs.
post #50 of 91
Thread Starter 
Thanks Bill. Reversing phase to 180 degrees did the trick. Gotta love DSP...one click and voila, dip gone! Did some quick eq'ing which I'll have to return to later, but so far it's looking good.

OmniMic V2 system measurement @ 1M (SEOS-12/TD12M/DNA-360), Track 12, Right Channel - Short Sine Sweep, Subs On, Phase 180, PEQ.
post #51 of 91
Thread Starter 
1st post edited with gratuitous shot of OmniMic V2 measurement session. Having fun with my new toy! smile.gif
post #52 of 91
Hey Bunny,

I am trying to gather parts for the x-overs, and PE does not have L3 3.5mH #266-569. What did you use?

Does this work?

http://www.parts-express.com/pe/pshowdetl.cfm?&Partnumber=266-560&scqty=2

Also, the x-over parts for this build is pretty cheap. I got 20 parts in my cart (for 2 builds) less the L3 above, and they come out to about $50. Just making sure I am not missing anything.

Thanks,


EDIT: Nevermind, saw your first post. Is this the one from Miniscus?

http://meniscusaudio.com/350mh-15sl-p-727.html
Edited by smokarz - 1/26/13 at 8:58am
post #53 of 91
Thread Starter 
Yep that's the one I used from Meniscus Audio. At the time PE was out of R3 so I got those from MA as well. All three XO's totalled ~$150.
post #54 of 91
Thanks,

Do you now if the one from PE that I linked above would also work?
post #55 of 91
Thread Starter 
Sure thing smokarz. While it might work, Bill did mention lower resistance would be better. I'd opt for the erse here: http://www.parts-express.com/pe/showdetl.cfm?partnumber=266-916 It has low dcr and a higher power rating as well.
post #56 of 91
Thanks RB. Good point, rather be safe.
post #57 of 91
So, what do you think of the speakers 6 months later? My TD12X build is nearing completion as we speak.
post #58 of 91
Thread Starter 
Loving them. I listen to at least a few songs every day. Detailed and revealing, but not bright or fatiging at all. Vocals are excellent and with a really good mix, they disappear in the room. I've never heard a soundstage with imaging like these. Still running phantom center too...and bare mdf. lol. I just don't want to take them apart to finish them, I'd have withdrawals! tongue.gif

I'll be building the SEOS-AT1/TD10M's soon for surrounds. I'll cook up a new thread for that one...

-Nate
post #59 of 91
Definitely glad to hear you are very happy with them Nate. smile.gif
post #60 of 91
Where are the final pics? Last pic showed them without the phase plug in the raw cabinets.
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