Dual 12" OB H-Frame Construction

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bdp24

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Re: Dual 12" OB H-Frame Construction
« Reply #40 on: 3 Aug 2014, 02:06 am »
Captain---The reason I was thinking of Velcro is because the magnets are so attracted to each other that getting the grills back off after they are inset into the H-Frame might be a problem. Velcro holds, but without the strong magnetic pull. I would never be using H-Frames without grills, so the look of Velcro wouldn't be an issue. Speaking of grills, I watched a friend of mine while he put new vintage reproduction grill cloth on my '67 Fender speaker cabinet; he stapled the cloth onto the back of one of the short ends of the grill frame and then stretched the cloth as tightly across the length of the grill as possible, stapling the other end of the cloth to the back of the other end. Then he did the same across the width. He told me the longer the length of cloth, the more it stretches (makes sense), so length first is the way to do it. With a pair of scissors he cut into the corner at a 45 degree angle, then cut off the extra material (to get rid of the bulk), and folded and stapled the cloth onto the frame. The stapler he used was pneumatic, with staples having a depth of about 1/2". The cloth now sags just a little in the middle, but it is much thicker and less stretchy than the cloth anyone here would use, and was very difficult to pull even as tightly as it was. I would pull the cloth as tightly as possible without ripping it---the 3/4" MDF grill frame won't bend from the pull of the cloth.

Captainhemo

Re: Dual 12" OB H-Frame Construction
« Reply #41 on: 3 Aug 2014, 04:38 am »
Jay,

I was thinking along the lines of Ed's suggestion about insetting the grill but that really looks good.

Mike

Thanks Mike  hoping there will be enough metallic in this paint to get some of the same contrast  that I get with the  OB7 grills when the light hits the paint.  I actually considered going with the same color  on the subs , was a bit torn between  the  contrast  and the versitality of going darker (goes with  anything) .  The decision was made for me when I found out  that this paint is no longer  available in Canada but I did mange toi find a few cans of the  metallic graphite so boought them.   I could have ordered the same charcoal I used previously but   Jegs wanted  close to $20 / can  for the shipping alone !

bdp24,
I hear you  on the magnets, wondered if that might be an issue with a recessed grill. I even wonder if the velcro would cause problems...if the grill is actually flush or below the surface of the outer panel, it could prove   really hard to   remove.  Don't really see how you'd grab it
Thanks for the  clothng ideas.  I've never had any issue withe geting the cloth nice and tight ( thin stuff)  just those dam corners are  messy .   Was thinking of  45'n  the excess in the corners already, may have to give it a try.  There are some tutorials   ouot there too

-jay

bdp24

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Re: Dual 12" OB H-Frame Construction
« Reply #42 on: 3 Aug 2014, 10:41 am »
     Some of the speakers in the 60's and earlier with inset grills actually had nothing holding them in place except the friction of the frame and cloth against the inside edges of the cabinet. When I got my first pair of real hi-fi speakers (AR 4ax's) I wanted to look at the drivers, and I just (carefully!) put a butter knife into the space between the grill and the cabinet and pried the grill off. No harm done, but I was kind of surprised by how crappy the drivers and baffle looked. No one would want to listen to speakers with the grills removed back then if it meant having to see the hideous looking baffle (glue smears, ugly particle board, not MDF), woofers and (especially) tweeters. The irony is, grill cloth back then was so thick (like burlap!) and acoustically non-transparent that the speakers would have sounded better without the grill cloth between the drivers and our ears. The frequency response was tailored to compensate for the cloth, but still.
     For these H-Frames, I won't be removing the grills after they are put in place anyway, so I'm not concerned about the appearance of the Velcro. Grills mounted to the front of the frames, such as yours, are unquestionably much easier to add without having to modify the frames. I just really like the old school look of AR, KLH, Dynaco, Advent, Klipsch (they are STILL made with inset grills), etc., speakers, with the grills flush with the front edges of the cabinet. For those getting Jon's H-Frames, the inner side panels and horizontal brace can be cut back an inch, and grill frames made to fit in the recess, for those who also like the old look. Either way, these are fantastic subs, aren't they?!
« Last Edit: 3 Aug 2014, 03:00 pm by bdp24 »

Captainhemo

Re: Dual 12" OB H-Frame Construction
« Reply #43 on: 7 Aug 2014, 12:44 am »
Here's the grill frame with a coat of paint, just some Satin Black Behr Premium Primer/Paint

I went to the local store that usually carries the cloth,  found out they are moving and have cleared  everything out and aren't bringing any more in until after the move.  I had to order a yard from  Vancouver, hopeuflly it will show up by   Fridday

Cabinet  all primed up with Bulls Eye 123. primer/sealer , this stuff seems to adhere extemely well to the MDF




I picked up a bag of these M8 x 13mm threaded inserts , going to give them a try instead of the inserts that come  with the spikes


Gong to  get the  top coat on in the next day or so. 

-jay
« Last Edit: 7 Aug 2014, 06:57 am by Captainhemo »

PDR

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Re: Dual 12" OB H-Frame Construction
« Reply #44 on: 7 Aug 2014, 05:11 am »
Great job, looks like its going to turn out VERY nice!..... :thumb:

Captainhemo

Re: Dual 12" OB H-Frame Construction
« Reply #45 on: 8 Aug 2014, 04:29 am »
Great job, looks like its going to turn out VERY nice!..... :thumb:

Thanks Perry :)
After I last  "talked" to you, I did a bit more research on the Poly Diffusers and found a thread  in the GIK circle where Bryan recommended  a diffuser behind each   OB speaker. Decided to give this a try and it is working well.  Planning to eventually replace  with a couple of the PI Audio diffusers  but for now these are staying put

Anyway , sprayed the top coat on this afternoon.   Here is a shot of the  Metallic Graphite trying to show  how much it changes   in the light,  had to sue the flas as it was already  sundown when I took these


And here are a couple of the cabinet itself




I'm pleased with the resuults, I''ll  grab a coule shots tomorrow afternoon when the sun  is poking through the back door of the garage.
Now I  just need that grill cloth  and more importantaly,  a delivery from  my buddy who has the packages from Danny  ,.. right Holmes  ?   :lol:

-jay

monte

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Re: Dual 12" OB H-Frame Construction
« Reply #46 on: 8 Aug 2014, 10:45 am »
Jay, looking good. Those early Christmas presents are fun to open. Keep up the good work .
Paul

Mr. Oczka

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Re: Dual 12" OB H-Frame Construction
« Reply #47 on: 8 Aug 2014, 02:26 pm »
Damn, those look fine!!!  Just curious, how did you apply the sealer?  What brand paint did you use for the metallic Graphite?

thanks,

tom

Captainhemo

Re: Dual 12" OB H-Frame Construction
« Reply #48 on: 8 Aug 2014, 03:53 pm »
Jay, looking good. Those early Christmas presents are fun to open. Keep up the good work .
Paul
Paul,
Yes they are  !   Looking forward to it

Tom,
I found a can of the BullsEye 123 primer/sealer in a spray bomb so I used that.. however, the 1 can I picked up was not enough so I  went back and  decided to get a  liter can which  was about 3 times the quantity of paint for the same price.  I rolled  it on and  just gave it a light sanding with a block .
The paint is made by Dupli Color

-jay

ebag4

Re: Dual 12" OB H-Frame Construction
« Reply #49 on: 8 Aug 2014, 11:58 pm »
That sub turned out great Jay, nice job.  I will likely be spraying my next project with rattle cans, I pickup up some Duplicolor metalcast to practice with, painting has never been my strong suit but I am encouraged by your excellent results.

Best,
Ed

Guy 13

Re: Dual 12" OB H-Frame Construction
« Reply #50 on: 9 Aug 2014, 03:22 am »
Hi Jay.
May I say that the color of your enclosure is not my favorite color.
(I prefer lighter color, but that's your choice and I really respect that.)
That's being said, I love your wood work and the paint job.
I wish my subwoofers would look as nice as yours.
I think with front grill it will makes a better looking enclosure,
that's what mine are missing.
I am riveted to my computer's screen to see and enjoy the end result.

Guy 13
 

Captainhemo

Re: Dual 12" OB H-Frame Construction
« Reply #51 on: 9 Aug 2014, 04:42 am »
That sub turned out great Jay, nice job.  I will likely be spraying my next project with rattle cans, I pickup up some Duplicolor metalcast to practice with, painting has never been my strong suit but I am encouraged by your excellent results.

Best,
Ed

Hey Ed, thanks for the comments.  if I can give you one tip for painting,  it would be prep, do lots of block sanding and get  everything as good as  you can   With every project,  I do more prep  and  end up with better results.  Learning my lesson :)
 Not sure if anyone else is using it , but I was  really impressed with how well that Bulls Eye 123  primer/sealer aheared to the MDf and  it covered very well too.   I let it dry overnight  and then give it a quick sanding  with a block  and some  240 , then a final   pass with 400. 

Guy,  no worries,  everyone has different  tastes in color.  As I mentioned  earlier in the thread,  I  almost went to the same color as the OB7's which is a shade lighter, almost silver in the light.    Unfortunately,  I can't get that paint in Canada anymore  but did manage to find some of the graphite so that really helped make the decision .  This stuff will   stand out pretty well  in the natural light I think

As for the grill, well , here you go


I'll post a bit more about the fiasco with the grill cloth tomorrow,  need to jump inthe shower and   have a Corona after, maybe even a couple, time to relax  :beer:

Oh,   figured I'd share this too as I know there are a few dog lovers out there....  Roxy likes to hang out inthe garage and  watch the projects  progress, crazy dog even stays in there when I'm  running the table saw  or router   !!

 
-jay

gregfisk

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Re: Dual 12" OB H-Frame Construction
« Reply #52 on: 9 Aug 2014, 06:24 am »
Jay, those look great! I like the grills, gives them a nice finished look especially with the softened inside corners.

I think Roxy is just keeping a watchful I on you, you know in case you make mistake and need to be saved :o

Guy 13

Re: Dual 12" OB H-Frame Construction
« Reply #53 on: 9 Aug 2014, 06:30 am »
Hi Jay.
I really like how your grill look like.
I would like to do the same with my enclosures,
but unfortunately, it's too late now.
I have to tell you a little secret,
I've hired your pouch to spy for me on how to do wood work.
He will report to me, when he know how to use the computer.
Next step, the woofers ?

Guy 13

bdp24

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Re: Dual 12" OB H-Frame Construction
« Reply #54 on: 9 Aug 2014, 10:03 am »
Handsome cabinet AND dog! The grill looks as good as the cab, and keeps listeners from thinking about the sub's "guts" too much. Now, after you install the woofers, let us know what you think of the sound, the ultimate point of all the work.
« Last Edit: 10 Aug 2014, 04:53 am by bdp24 »

Ron

Re: Dual 12" OB H-Frame Construction
« Reply #55 on: 10 Aug 2014, 03:06 am »
  Excellent job Jay. Your OB H-frame cabinet looks great!  :thumb:  I'm anxious to hear your report on how it sounds
once you get the components installed and have a chance to test it.

Ron

Captainhemo

Re: Dual 12" OB H-Frame Construction
« Reply #56 on: 10 Aug 2014, 03:47 pm »
Thanks for the comments you guys, really looking forward  to getting it up and running.

Funny about the dog Greg,  she definitely likes to keep an "I" on things and now I know why  Guy !! Guess we'll know why a couple boxes of Milk Bones arive from planet Viet nam huh  ?  :lol:

Cody698,  I found this  which may interest you, 
https://www.youtube.com/watch?v=BQ1H3_uv2uE

I tried to  do the same basic  thing as the video shows but am still too ashamed to show the  rear  ,  not pretty.  My biggest mistake was not  using quie a wide enough piece of cloth,  had I made it an inch or two wider to start with,   it would have been much better, I ened up having to really stretch the sides over to  just get a staple in .  Lesson learned for the next one. 
With the much more flexible grill cloth we typically use,  you still can end up  with a bit of a problem in the corners but  I  just used a little  bit of  adhesie on a q tip   right at the corner on the rear which helped a lot

-jay

monte

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Re: Dual 12" OB H-Frame Construction
« Reply #57 on: 10 Aug 2014, 04:03 pm »
Jay, do the speakers and amp come in kit form or do you buy them separately.

Captainhemo

Re: Dual 12" OB H-Frame Construction
« Reply #58 on: 10 Aug 2014, 04:23 pm »
Jay, do the speakers and amp come in kit form or do you buy them separately.

Seperately, but, just give Danny a call and he will set you up with all the components you need.  remember too,  if you are only doing  dual  driver OB  (H, W, U frmes), not triples,  he has the new 8 ohm  drivers coming in shortly

-jay

monte

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Re: Dual 12" OB H-Frame Construction
« Reply #59 on: 10 Aug 2014, 04:47 pm »
I believe I read that the 8 ohm 12's would be in around the end of Aug.