Ideas on Sunflower cabinet design

[oneplustwo]

Sorry if you guys are getting bored of this stuff. Got some painting done today:







I suck at painting. And I don't like doing it. Actually, that's probably one reason I suck at it. So I'm not super happy with the black, but if you don't look too close it looks ok. I might try redoing it. Haven't decided yet. Kinda anxious to hear them!

[john trials]

Those are really looking nice! I really like the light/dark contrast.

[oneplustwo]

Got the drivers bolted in and the woofer crossover installed.





The rest of the crossovers are being soldered up now. Still need to figure out the box though. I'm not sure I'm happy with iteration #2 so there might be iteration 3-way3.

[a-rone]

Man these are awesome. Congrats on the progress thus far. Your cabinet design is fantastic. I just might have to copy what you have done. :T

[oneplustwo]

Thanks! Putting the drivers in was very satisfying! I'm super happy with it so far with the exception of the so-so black paint job. But the tung oil on the wood is exactly what I was hoping for. Just a little more work before I can actually hear them!

[a-rone]

I know very little about the DIY thing other than my near obsession of lurking on this site. This design for the $ is leading me to think seriously about jumping in the pool head first. Do these speakers require a lot of power to drive?

[pereze]

Interested to hear your impressions

Wow, these look great. I have been very interested in doing a ring radiator speaker after hearing a pair of Sonus Faber's and found the sunflowers a while ago. The XT25 sounds like an amazing tweeter from the reviews.

I have most of the parts to build the Nat P's and haven't even gotten around to that yet. I was finally going to start building my Nat P's (have had most of the parts for over a year) so I was re-reading up on them and saw this post.

Now I really want to build these...

[oneplustwo]

@a-rone: I'm not sure I've seen any sensitivity numbers on these... maybe Paul can comment. I don't need huge SPL and my room isn't that big so I'm not really worried about it.

@pereze: I'm excited to hear this tweeter as well. Get those Nat P's built so you can move on to project #2! Once you start, you can't stop!

[justanie]

Wow, great looking speakers, these speaker sound great, you will not be disappointed.
They remind me of mine , I have the same basic design with a few modifications. I use different woofers, 1. because i had them on hand, 2. it allows me to use a narrower baffle with longer wings. I built them with removable baffles and tuneable ports, it makes it really easy to change drivers when i get the urge, which is way too often.

I also built a kinda matching center.

Heres a few pics....

Justin.

[justanie]

Heres the center and surrounds.

[oneplustwo]

Crossovers soldered up with the box pieces cut and dry fit:

[oneplustwo]

Got the crossover boxes done and everything wired up last night!

They sound great based on very little listening so far! The RS225 does a really nice job holding down the bass... I didn't expect it to go down that low with that much authority. I think I'll be able to dedicate the subwoofer project to strictly .1 LFE duty. Although I'll probably play around with it in music too just to see if there's much incremental difference on bass heavy music.

I didn't have much time to do any real critical listening, but ran through a bunch of different genres to see if there were "issues." None so far, everything sounded pretty good. I'll have more comments after I get them properly situated and have more time to listen to familiar material.

Here are a few pics. I'll probably do some "glamour" shots later.

[john trials]

WOW! Those look really nice, even from the back. I like the Speakon, too. Great job!!!!

[richnen]

Very nice work, bring on the glam shots! :T

[oneplustwo]

Ok, it's not a glam shot... these things are too damn heavy to situate for a proper glam shot! But it's the sock shot. With the baby gate (think of it as an acoustic treatment.)

[Undefinition]

Some seriously nice woodworking there. Did you use some sort of pore filler to get that so smooth?

Ironically, my living room speakers are employing that same baby-proofing system. So far it's working well (fingers crossed)

Which version of the crossover are you using? (EDIT: Nevermind, I just looked at the physical parts layout, and saw that it's the Redux)

[oneplustwo]

Some seriously nice woodworking there. Did you use some sort of pore filler to get that so smooth?

Thanks, although not that serious... I made tons of little mistakes. No on the pore filler... just progressively finer sand paper to 220 and then 3 coats of tung oil with some steel wool in between coats. And actually, I just noticed one of the ply layers is delaminating on one of them... probably because I used that section as a handle when moving them around. Oops! I think I can get away with a little wood glue and clamping to fix it. That's the beauty of just tung oil though. Should be able to fix easily without having to redo the finish much if at all.

Ironically, my living room speakers are employing that same baby-proofing system. So far it's working well (fingers crossed)

Yah... the kids can still reach the MTM section but I've already warned them off with some unexpected volume.

Which version of the crossover are you using? (EDIT: Nevermind, I just looked at the physical parts layout, and saw that it's the Redux)

You got it! Got some spare parts lying around now! I still need to seal up the hole in the crossover box that feed the large hole that was supposed to be the l-pad location. Not sure if it will make any difference at all though... maybe I'll just leave it alone.

[oneplustwo]

I think my room is causing the right side to sound "hot". It's got the bookshelf behind it and it's closer to the corner where the left side is open to the dining room area (clear from my sock picture above.)

Also, the bass is a bit heavy for me. Not sure if it's that I'm just used to the RS180s from the ZDT and they didn't go as low or if maybe I need to tune the port and stuffing to taste. Just stuffing the port with a stuffed animal seemed to help already. (LOTS of those lying around.) That being said, it's very material dependent too. Some sound fine to me, and others sound way to heavy. Not sure if it's how things are mixed with engineers expecting "lesser" reproduction capabilities.

[Marvin]

I think my room is causing the right side to sound "hot". It's got the bookshelf behind it and it's closer to the corner where the left side is open to the dining room area (clear from my sock picture above.)

Also, the bass is a bit heavy for me. Not sure if it's that I'm just used to the RS180s from the ZDT and they didn't go as low or if maybe I need to tune the port and stuffing to taste. Just stuffing the port with a stuffed animal seemed to help already. (LOTS of those lying around.) That being said, it's very material dependent too. Some sound fine to me, and others sound way to heavy. Not sure if it's how things are mixed with engineers expecting "lesser" reproduction capabilities.

So how does the open back sound compare to what you are accustomed to? Imaging / staging better or worse?

Your room and furniture arrangement don't appear to be ideal for consistent reflected sound, so I'm curious how you like it.

Nice work on the cabinets! :T

Marvin

[oneplustwo]

So how does the open back sound compare to what you are accustomed to? Imaging / staging better or worse?

Your room and furniture arrangement don't appear to be ideal for consistent reflected sound, so I'm curious how you like it.

Nice work on the cabinets! :T

Marvin

In comparison with my ZDT3.5, I would say the imaging and staging are pretty close. But I'd give the nod to the ZDT. This might be because the open back is more influenced by the room setup and as you mentioned, my room is not setup well. I haven't done back to back blinded A/B testing or anything close to resembling a "real" test so take it for what it's worth.

I do like the look of these quite a bit though! And the bass seems to go deeper. The midrange of the ZDT is hard to beat though. Ultimately, I love both pairs! They're just... different.

[AdelaaR]

Those, sir, are beauties

I like the nice woodtexture and finish on the crossover boxes in particular.

[john trials]

I'm just curious: What is the preferred surface behind a pair of OB speakers? Diffuse or specular reflecting, absorbing, nothing (open space, which I guess would be similar to absorbing)? Is there a preferred surface, or does it just depend on how the crossover is voiced?

Behind your left speaker, there is half open space, half specular reflecting. Behind the right speaker, there is diffuse reflecting (and maybe a little absorbing) in the bookshelf.

[oneplustwo]

@Adelaar: Thanks... the crossover boxes were a bit of an afterthought since I started the project before the Redux crossover was introduced but I'm happy with how they turned out. Made a few mistakes on them, but not bad for my amateur skill-level.

@john: Good question! My guess is diffuse would be preferred but I will defer to the experts. At the very least, the left and right should be matching!

[Undefinition]

Hmm... well, I won't rest until you're satisfied

So, first let's address the left/right issue. Just to eliminate other issues, did you try swapping the speakers and/or crossovers on the left and right sides? Many times myself I find myself fidgeting with all sorts of things, only to realize that something was wired incorrectly.

As for the bass, yes the RS225 does definitely dig deeper than an RS180. Extension is usually a good thing--"heavy bass" on the other hand, on the other hand, well that's not really the goal of this design. What is the vent size + length you have right now? is the cabinet lined or stuffed?

[oneplustwo]

Hi Paul,

Thanks for the comments!

For left/right: I have not tried swapping yet. The difference is pretty subtle and I'm almost sure it's the room setup. With the baby gate and everything, it's kinda hard to swap things around but I'll give that a shot just to make sure nothing else is wrong.

For the bass, the vent is the spec'd one... I think the 2" precision port? And I went in the middle of the range you suggested which I think was 7". The cabinet is mostly lined with 2" foam. However, there is a section in the middle that is not lined. I can't for the life of me remember why I didn't finish them off... No stuffing yet, but that was something I was going to experiment with as well.

Thanks in advance for any insights/suggestions!

[BOBinGA]

oneplustwo,

I have speakers very much like the Sunflowers - RS225(ported)/RS150(open back)/27TBFCG - and I also had a hard time getting the bass just right. Every ported speaker I've ever heard needed something to tame the "ported box sound" and in my case it was a lot of stuffing directly behind the woofer. I have my woofer mounted pretty high in the cabinet like the Sunflowers and I used a lot of polyester batting in the top two-thirds of the box. I found that stuffing works best directly behind the woofer. This is similar to mass loaded tranmission lines (even though mine is a standard ported box and not a TL). I'm of the opinion that the reason people like TL speakers is because of the heavy stuffing directly behind the woofer and not because of the TL per se. So do try some (or a lot of) stuffing if you find the bass a little too boomy.

-Bob

[oneplustwo]

Hi Bob,

Thanks for the tip! Directly behind the woofer is actually where the foam is missing. But I can position the stuffing there pretty well given that's where the brace is.

-Jason

[Undefinition]

Hmm... I checked Precision Port's website calculator, and I think you might have that thing tuned kinda high, which is going to cause some peaking in the low bass.

http://www.psp-inc.com/tools.html

According to them, to tune the thing down to 22 Hz--which according to my sims should be flat--requires a vent that is 11.5" (including the flare)!

Even the tuning I have mine to now (28 Hz) requires a vent that is 7" (including flare).

Nonetheless, you can (and should) still experiment with some polyfil in the woofer enclosure. My rule of thumb for polyfil is to fill the cabinet up, then listen, and start taking out a few handfulls until the sound just sort of "clicks" and sounds big and effortless--and no longer choked.

[oneplustwo]

Hi Paul,

Thanks for the research! For some reason, I had it in my head that the 7" you used was what I should be using for mine. Did you not use a 2" port? Or is it that the flare on the precision ports are larger in radius? I'll double check the port diameter I have and make sure I'm not lying to you as far as those details.

-Jason

[oneplustwo]

Update: Got the polyfill in... just put a large puffy wad behind the driver and under the port. It seems to have tamed the bass to my liking! Also, just a side note, I don't think I need a sub for HT either although that won't stop me from building one! Watched Tron last night and the bass was just fine as far as I could tell. Maybe I don't know what I'm missing though... thus, the sub will be built. Eventually.