SuperPensil12 Variation with curvy sides

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Hello,

I want to build either the SuperPensil 12 or the Pensil 10.2. The only issue i have (or rather: my girlfriend has convinced me I have to have :D) is that they look a little "chubby". In another thread I have seen someone model a modified pensil with curvy sides that I really liked the look of, but didn't go on with it because of problems with properly bracing this particular design.

In the same thread dave stated the most critical features of the pensils like this:
Cross section area, line length (height), driver placement from the top, terminus area, placement* & depth (don't go building a 2" baffle)

* ignoring room effects, they have been successfully placed on the back and should be no issue on the side.

So, what I came up with is this:
  • reduce the baffle width
  • increase the depth accordingly, so that the same cross section area is achieved
  • modify the terminus dimensions in the same way, so that it has the same area
  • overall height and driver placement is unchanged
  • put "curvy sides" on the whole thing. The gaps left by this will be filled with sand.

What do you think, is there a chance that this can work (just assuming that I can successfully build them like that)?
 

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Hey there, I think it might be easier to use the top and bottom as a template to wrap multiple this layers to produce the curve. Wouldn't be too hard. Problem is, the bending ply meterial is very low density. It might be best to use thin mdf or masonite.

Also, I thought they would look chubby as well (my 10.2's) but the hard bevel solves that problem.

http://www.diyaudio.com/forums/markaudio/203343-ryans-pensil-10-2-build-log-3.html

My wife just smiled when I brought them in an rates them a 10 out of ten on the WAFometer. I think that's a BS rating but the point is she likes them.

They sound great so go for it!

I think the microtower from Dave's website Planet 10 has perhaps the ultimate WAF.
http://homepage.mac.com/tlinespeakers/FAL/downloads/microTower-maps-150909.pdf
 
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You mean curving the top and bottom, and then use that as template for ribs that have the same curve and run from front to back? I hope thats what you meant. I have thought about that solution , but it would almost be impossible to fill the remaining gaps with sand, and I wouldn't want to leave it empty.

As to what material would be best for the curved sides: maybe I will use just regular thin birch ply, you can get it in 5 mm thickness I think. That should be stiff enough.

I think the microtower from Dave's website Planet 10 has perhaps the ultimate WAF.
http://homepage.mac.com/tlinespeakers/FAL/downloads/microTower-maps-150909.pdf

Those are planned for the rear ;). That only leaves the question what to use as center. But thats something to be discussed at a later time.
 
Hilmar_G,

Some of the more experienced folks say that for vocal purity you gotta match the front speakers and center; so if Pensil 12 is your cup of tea, an Alp 12 center will be good. Skeeter99 recently added a A12 center to his Super Pensils recently - you can look up his thread.
 
Yes the curved top/bottom/dividers with holes as templates. You would not need to use sand. 5mm birch might work very well in 2 or three layers.

Have you considered using the 10.2? It sounds like you are using these in a system that has a sub-woofer. How much low end extension do you need?

I'm considering the Mar-Ken 7.3 or 10.2 for center channel with pensil 10.2's as mains.
 
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I am not yet decided if I want to use the 10.2 or the 12. I do have nice Ripol-subwoofers that go way below what I am able to hear, but I wanted to be able to listen to music without them.
As for the center speaker, I have only limited space, so the speaker can be wide and even deep (30 cm should not be a problem) but can't be very high. I will probably go for the Alpair 7 for this and then see what enclosure fits the bill.

But what I really wanted to know in my first post was whether or not the altered dimensions I came up with would affect the sound. I don't want a guarantee for that, just an educated guess would be nice. I know that messing around with a proven design just for optical reasons is sometimes frowned upon, but for me looks are important, and thats why I like diy, you can build it just the way you want it.
 
Are you using a home theater reciever that allows high pass and distance correction? If so I would recomment the 10.2 or even the 7.3 with a high pass. @ 45hz high pass my pensil 10.2's have very little excursion and so very low distortion. Let the subs do the heavy lifting unless you are in a small room. Mine is 25x20 with 15 foot cielings. A subwoofer is essential for me. There is a lot between 20-40 I don't care what anyone says. The lower the crossover point the more seemless the integration is.

Keep in mind I have not heard the alp 12 but it only goes a little bit lower than the 10.2 according to a comparison thread that is on here somewhere.
 
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