Walnut H9800

[matsj]

You can buy them new . I lost one pair of my drivers to my project, but i will look forward. Keep posting how it goes forward.

mats

[Zilch]

Zilch, any last minute pointers on modifying a compensation network to this measured response?

Build the Timbers "Key" network (<$50 apiece) and post the resulting response.

http://audioheritage.org/vbulletin/s...808#post143808

Looks like you need its notch at 1.8 kHz.

Here's what I got on H9800:

http://audioheritage.org/vbulletin/s...142#post137142

Beautiful horns, John....

[Joe Alesi]

John it looks superb. I really like your idea of using an overhead router on a radial arm . I would say it took LOTS of passes of the router and heaps of sanding? for that shape. What sort of router bit did you use- I would have thought you needed a round bottomed radiused cutter, but it looks cylindrical in the photo.

Well Done

[John W]

I used a couple bits. The bit used most was a cove profile with a 1/2 inch radius. The top part of the bit that normally has the bearing was ground off a couple years ago for some other project. The one in the picture is a round bottom core box bit, this was used mainly on the inside profile.

It did take a lot of passes. One advantage of the setup is that there are two adjustments possible in the vertical direction. One by the arm of the saw, and the other by the vertical adjustment of the router housing. I carefully adjusted the bit to match the intended profile with the router at a fixed stop in the maximum downward position. Then for the other three blanks I could raise the router and take multiple light passes down to the final depth without having to re-adjust.

I actually finished off the profile with a spokeshave, scraper and sandpaper. This went pretty quickly since you are basically just knocking the tops off a bunch of little peaks, then sanding smooth to the bottom of the rounded valleys.

[Joe Alesi]

Excellent John,

I'd love to do the same thing for my 2441s. At one stage I contemplated several laminations of solid timber/ply cut into a thick cylinder say 24inches in diameter and 4 inches thick placed on a turntable bearing and rotated under some form of adjustable cutter- router, grinder with gouging wheel even a circualr saw blade at a compound angle and then sliced up like a cake into four quarters- enough for 2 horns- One day...

[Guido]

Beautiful John!

I wish I could do that but I'm more the "electrical" guy

[yggdrasil]

Again, let me say that your abilities with wood is simply amazing.

I made a similar jig last year when wanting another shape on tractrix horns. http://audioheritage.org/vbulletin/s...ead.php?t=8363 After a few test rounds the resulting horn tested just fine.

Here's a picture of the system in development.

[grumpy]

To those producing and using plots... are you doing some sort of spatial averaging that
each other understands (such that combining plots and suggested frequency
tailoring might produce somewhat predictable results and avoid unnecessary
tweaks or concerns )? I'd like to see these horns perform as well as they are
capable

I don't recall reading any agreed-upon method (sorry if I've missed it).

-grumpy

[merlin]

Utterly gorgeous - you have made me very jealous!

When it comes to horns, there's an enviromental dilemna. Whether to destroy the earth's rain forests by over de-forestation, or to poison the atmosphere for our children with toxic byproducts of plastics manufacture.

I say let's lose those trees. You make them look so nice.

[Zilch]

To those producing and using plots... are you doing some sort of spatial averaging that each other understands...?

http://audioheritage.org/vbulletin/s...633#post153633

[Mr. Widget]

As always... just beautiful John!

From the pics it looks as though you decided to omit the fillet that starts out really tight in the bell and eventually grows to a full 0.75" radius at the mouth?

With my CNC, I couldn't keep this fillet in wood and had to resort to adding bondo as the fillet edge became knife edge thin and blew out... I wonder how leaving it out affects the sound?

In any event, it sure is pretty... nice work.


Widget

[Titanium Dome]

Very attractive horns. Congratulations on a fine result.

I'd allow a pair that wonderful-looking in my house, but eventually would want to pass them on to someone who really cherished them.

The overall design of the system is beautiful.

[sa660]

You turn wood in precious engineering creation.
Well done!!!

[JBLRaiser]

time for such an intricate project? A very impressive horn.

[UreiCollector]

Absolutely STUNNING work!!! I'm impressed!!!