Homemade Pair of Klipsch Belle's/La Scala

[PerchPerkins]

Greetings all! 

I need input on me design
Being a broke college student (mechanical engineering) means that I love to build and design things and I also have no money. 

That said, The Klipsch La Scala and Belle models have intrigued me. 

recently I designed (but not built) a quarter wave transmission line enclosure for a 8" subwoofer I have (Tymphany NE225W-08). 

The La scales and Belle's have intrigued me so much that I decided to design a version of the Belle's that, instead of a sealed enclosure in the middle, has a transmission line enclosure. The transmission is tuned to the Fs of the speaker (free-air resonant frequency) which is 32 Hz and would give deep accurate bass down to 25 hz after this.

Between the Speaker and the port of the transmission line, there is a 3" gap and two 3" openings on either side, which then tapers up to a 10" opening at the front of the speaker. Here I have a side view, and a top view of the transmission line and my version of the Belle.

Does anyone here know anything regarding the design of the Belle and La Scala? is there a way I should optimize the Gap between the speaker and the back panel and the horn opening based off of the woofer I am using or will the 3" gaps be adequate?

 

Does anyone here know about how to optimize the design of the horn design to work with a specific woofer in a Transmission line enclosure?

 

[CECAA850]

• Take your speaker and find out what is the resonant frequency in free air (F_s).
• Find the corresponding wavelength for that F_s.
• Find the length of the transmission line by dividing that wavelength by 4 (the quarter wavelength).
• Make a path from the back of the speaker to the front of the speaker, which is exactly the length you just calculated.
• The path can take different shapes. A labyrinth is popular because it saves spaces (so enclosure doesn’t get enormous).
• Damp the path with different materials of various thicknesses.
• The damping material will absorb the upper frequencies, which introduce some resonance problems.
• If the upper frequencies are successfully absorbed, all that is left is the low frequencies from the back of the speaker, which will combine with those in the front.

 

 

Copy and pasted from HERE   Not my info.

[glens]

I'm guessing it will will work as intended, but not exactly so.  As the horn kicks in going upwards there'll be less "usable" downward extension than you'd have with a direct radiator so back-loaded.

[JohnA]

Look on the forum for La Scala drawings.  There is an accurate set floating around.  A Belle Klipsch is functionally the same, but used a smaller squawker horn because it has less depth than a La Scala.  

 

La Scala was built to be compact and material efficient.  That limits the bass horn length, limiting the fc of the horn.  Since you dont need to make a profit, look at a deeper, trapezoidal section in plan, keeping same flare rate.  If you can get down to 40 Hz, in room, you will have most music nailed (low E1 on a bass is 41 Hz, D1, ala Fallout Boy is 37 Hz).  Firing a port into a horn works, but the horn still should be long enough.

 

Get a copy of HornResp or similar to model your designs. 

[pzannucci]

On 9/13/2019 at 4:18 PM, PerchPerkins said:

Greetings all! 

I need input on me design
Being a broke college student (mechanical engineering) means that I love to build and design things and I also have no money. 

That said, The Klipsch La Scala and Belle models have intrigued me. 

recently I designed (but not built) a quarter wave transmission line enclosure for a 8" subwoofer I have (Tymphany NE225W-08). 

The La scales and Belle's have intrigued me so much that I decided to design a version of the Belle's that, instead of a sealed enclosure in the middle, has a transmission line enclosure. The transmission is tuned to the Fs of the speaker (free-air resonant frequency) which is 32 Hz and would give deep accurate bass down to 25 hz after this.

Between the Speaker and the port of the transmission line, there is a 3" gap and two 3" openings on either side, which then tapers up to a 10" opening at the front of the speaker. Here I have a side view, and a top view of the transmission line and my version of the Belle.

Does anyone here know anything regarding the design of the Belle and La Scala? is there a way I should optimize the Gap between the speaker and the back panel and the horn opening based off of the woofer I am using or will the 3" gaps be adequate?

 

Does anyone here know about how to optimize the design of the horn design to work with a specific woofer in a Transmission line enclosure?

 

 

 

 

It appears you want fairly extended bass.  The horn itself will take up a lot of space let alone adding a TL with it.  A better approach would be something like a La Scala horn but enlarged enough to port appropriately to provide some bass extension.  Remember those ports will usually not keep up with the horn efficiency so you need to also figure how to manage that.

The size, length, compression at throat, back side volume, expansion rate will all contribute to the efficiency and frequency response allowed by the horn.

 

Fun project and will take a lot of trial an error if you don't just build a design with has already had the problems sorted out.  Enjoy though!! 

[moray james]

 

djk came up with a riser mod for a LaScala (or a Belle) which lifts the horn up (about 8 inches internal) and that volume is open to the dog house, the volume vents into the room (see attachment). Versions were done both with and without additional filtering response is extended downward into the upper mid 30 Hz. range. Making a Belle or a LaScala larger does not buy you very much. The Peavey FH1 shows this to be the case horn length being the major limiting factor. Ernst Georg Beck designed a very fine folded horn called the California which betters the LaScala University Classic/Dean horns and which provides excellent extension in both directions that you will likely not find bettered by any other horn design. Hope this may be of interest.