B&C DE10 upgrade/retrofit for KLF20/KLF30 K-79-K

[Iteachstem]

 I wanted to document my upgrade process for those of you who wanted to take the tinkering/budget approach to installing the B&C DE 10 driver into your KLF20/30 etc. speakers.  Feel free to ask any questions.

 

I purchased these drop in fit drivers for $36 plus tax on ebay:

https://www.ebay.com/itm/2-Paudio-PHT-409-Horn-Tweeter-Supertweeter-Klipsch-replace-K-79-K-75-K-76-K-84/372632527011?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

And the B&C Drivers:

https://www.parts-express.com/bc-de10-8-1-mylar-horn-compression-driver-8-ohm-2-bolt--294-600

 

Then, I disassembled them as you will only use the horn parts.

 

 

 

Remove the disc and cut out, dremel, sand, etc. these center phase plugs according to the pictures.  The B&C Drivers already have a phase plug inside the housing.

 

 

That concludes the modification of the lens assembly. 

[Iteachstem]

Next, I bought some bolts and washers to mount the B&C driver to the horn.

...and assembled the unit to test fit everything...

 

 

Then, I mounted the horn...

 

 

and then align and attached the driver.  Do not over tighten.

 

 

and connected the wires. (You need to cut the OEM connectors off and replace with larger ones)

 

Final picture:

 

 

 

 

Cheap horns about $40

B&C Drivers about $100

Misc. parts less than $10

 

I hope this was helpful!  So, for about $150 you can have a great upgrade to your speakers!

 

 

[DizRotus]

I like it.

[Iteachstem]

If anyone out there doesn't want to do all of the work, I have an extra set (Brand new) I built that I will sell for $175.  Pick up in the Western Burbs of Chicago. 60511

[Iteachstem]

Scratch that, I don't have an extra set anymore.😃

[Ford Galaxie]

Or you could do it this way.

 

1. 125” aluminum, cut out using a 4” keyhole saw.
2. Center bore cut out with a 1” hole saw.
3. Using an 3 bolt Klipsch diaphragm as a template fitted into the 1 hole , I drilled three holes and tapped to 8/32”.
4. Drilled two holes 3” apart through the center for the DE10.
5. Using a nibbler, removed the plastic dome in the Tractrix horn. Cleaned it up with a Dremel and some 80/120 grit sandpaper.
6. Using a cut down Allen wrench, I fastened the mounting plate to the Tractrix horn using 8/32 x 1/4” stainless button heads from the backside of the Tractrix through the threaded holes on the mounting plate.
7. The DE10 bolts on using 10/32 x 1/2 inch stainless socket heads.

 

 

 

There are some ways you can cheat pulling this off. I built this purely on backyard craftsmanship with common and cheap tools. Attention to detail and patience always guarantees success. Look at it as as a series of steps and focus on those steps to get the end result. When in doubt, step back away, think, drink some coffee and then tackle the next step.

I tried to be as exact as possible, but you could nail it by simply eyeballing it.

I used a precision cut 1 inch hole saw. A Milwaukee 15/16” hole saw will work well enough following up with some course sandpaper wrapped up in a circle to clean up the hole. Ace hardware.

If you don’t want to sacrifice a tweeter diaphragm and going through the trouble drilling and tapping to make a template, you could cut out the 1” hole, eyeball it and bond it to the horn with JB Weld.

It’s not too important that the spacing for the DE10 is exact. You just want the driver centered in the hole. You can oversize the holes to get the 2 bolt drivers to fit center.

Edited November 10, 2024 by Ford Galaxie

[winglet]

1/4” plexy works as well.  
 

 

[HorizonVibe]

 

Nice work!  It's cool to see how you're making these upgrades accessible without going all-in on expensive components.

[jjptkd]

I started a thread about this with the de-120 as well, very easy process:

 

 

[Woofers and Tweeters]

17 hours ago, winglet said:

1/4” plexy works as well.

Polycarbonate is easy to work with too.