Hello all,  I'm new to the site and just getting back to Audiophile equipment after a 40+ year hiatus.  I was recently given some very nice gear that was incomplete and needed work and the next thing I know I'm obsessed with Decware stuff and ordering my first items.  The problem is that I need higher efficiency speakers than the Spendor SP7/1's and Acarian Elons I was given.  I did inherit an Altec Voice of theater speaker from my mother, but it was for an early mono set up (Rek-o-kut turntable and Radio Craftsmen Amp) so I only have one.

Although I am a complete knucklehead about electronics I spent most of my adult life as a furniture maker and cabinetmaker.  Consequently the cost differential between drivers and finished speaker has led me to decide to make my own.

I ordered Lii Audio F-15's and am going to build baffless speakers a la Steve Deckert's design (with some styling modifications to personalize them).  I'm also making a couple of extra pairs for two friends.

Next I want to make a pair of the Lii Audio Reference speakers using Lii Silver 10's.  I would like to pretty much duplicate their design as I have to assume the specific internal geometry is intentional and specific.  Does anyone have measured drawings and/or photographs of the interior of the factory cabinets?

by the way, given the amount of labor required to make them, the retail price of the speakers is incredibly low--if you had them made here I suspect they would cost around 3 times the price.  My point is not that the cabinets are expensive, but with kids in college, I have more time than money so for me making them is the only option.

Any drawings or first hand experience with the speakers would be greatly appreciated.

Reed Karen
Shelter Island, NY

Thanks Brian, I appreciate it.

I emailed Lii Audio and they were gracious enough to send me measured drawings of their reference speaker cabinets for the silver/crystal 10's.  I am attaching the drawings as a resource for anyone else who is interested in building a pair.  I will leave the files large so that you have higher resolution if you want to print them.  I may have to post the second drawing set in a separate email.

Reed

25.4 is your friend when converting Metric to Imperial measurements!

There are exactly 25.4 MM to an inch.

Just trying to be helpful.

It is most generous of Mr Lii to share his cabinet measures and design with us. I am grateful.

Brian

Another Lii speaker drawing

Either of these look a hell of a lot easier to build than the Lii reference!

I guess it depends on how much of a challenge you want…

Lola works, thanks for posting the plans. I have excellent woodworking skills but I’ve never built a speaker and I have a few questions:

1.  The bracing. It obviously can’t be a shelf so, is it a circle with a cut out?  I don’t understand the drawing

2.  What is depicted in purple?  Is it foam? Some other dampening material?

Thanks to anyone who can answer for me

Gary

Look at both the plan and elevation drawing.  Yes, the purple are "rings" of reinforcing.

Thanks everyone.

I doubt there is an “internal frame”.  I’m experimenting with the OB’s now (breaking in Silver 10’s with DIY Betsy’s made from Sassafras) but if I am not satisfied I will move to the reference.

I’m thinking of two different ways to build the cabinets.  The first involves coopering; this method involves cutting the edges of a series of vertical pieces at specific angles so that they make a curve. This method would not work well with plywood but is well suited to solid wood.  The second involves kerf bending. In this method one builds a frame (that would then serve as the internal bracing). The plywood is cut with a series of non-through kerfs that allow it be to bent over the frame. In between the plywood and the frame, and glued to the plywood, one adds a layer of 1/8 inch bending plywood.  I’ve used this technique a number of times and it is very strong. It does leave small empty “voids” at the bottom of the kerfs. One could filll these with something (bondo glue?) but this would make the glue-up more difficult.

BTW, the choice of glue is important for this technique. PVA glues “give” a little so not the best choice. Hide glue or resin glue is better.

Is there any reason besides cost not to build out of solid wood?  Could use MDF but wold be very heavy. Would the voids present a sonic issue??

Any other ideas?

Gary

Looks like 5/8” marine grade plywood is used for the sides. I’ve done some coopering, limit forming, but mostly kerf bending in my life. After looking at what Lii done(did a search yesterday because I remember Lii talking about a steel frame in the reference when cabinets were upgraded), it would be the best route to get her done IMO.

Has anyone done plywood sheet forming? Basically it is wetting the wood and pressing it around a form, let it dry and it retains the form shape. Wonder if it would be better to use two sheets of 3/8 as compared to one 5/8. Or, 3/8 and 1/4 on the top layer.

I was thinking that if the plan was put in paint(if it is still called that in windows) it could be scaled and printed the actual size to use as a template to make the top and bottom forms and necessary forms for bending.

John

This is very helpful!  If the bracing is as important as suggested then gluing up a few sheets of bending plywood over a form might be best. Unfortunately, this would require veneer for a pretty cabinet and this would be difficult as it would require a huge vacuum press.  So, either a painted cabinet made from multiple plays of bending plywood, or kerf bending. Still wondering about the effects of the kerfs on the sonics.  I just rapped on a 3 inch wide piece of kerf-bent, glued up remnant from a project; seems to have quite a ring to it. So, either coopering or bending ply.

BTW, coopering should be easy if you have a table saw. Just calculate the angles

Gary

I’m experimenting with OB’s right now. If I decide to build the cabinets this discussion will be so helpful. Paper backed veneer would be a good solution.

I’m leaning against kerf bending but laying up 2 or 3 layers of bending plywood should work well. If a 3/8 inch carbide bit is used to rout the forms one would be left with both an interior brace and an exterior form ideal for the glue up.

Coopering would not be hard. I don’t find the finishing concerning. The internal bracing would need to be built separately. Choice of wood could be important; probably want a species with good damping properties.

Gary