Quick & Dirty 4430-Inspired Two-Ways Part II

[Ian Mackenzie]

Thank you, Rob.

I must say I was enlightened by the exchange with Mvaldes over the past few days. I learned a new way to use it for analysis and troubleshooting, and just looking at his curve suggested what the problem might be.

WAY cool bringing that from the other side of the world, yup....

Your clinic idea is GREAT! Let's do that. Mr. Widget's gonna help me get started. We should all share using CLIO here....

Zilch,

Has it arrived yet?..I hope I have given the right opportunity!

Playing around with speakers is like walking around an elephant.

Its a big subject and it takes a while to see the full picture.

Used wisely, Clio as a tool will give you a better appreciation of the big picture.

In reference to more recent posts an audio tool will always serve you best when used for the intended application. Words to that effect are in the fine print on many JBL professional brochures.

[Zilch]

A pair of LE85's get new ($500 with shipping) D8R2421 diaphragms. Alignment pins on the driver make installation simple and Zilchproof.

Here on same H3100, N3100, B380, as above. Delicious HF extension. Compare to 2426H (below).

Impedance sweep of driver and horn, bottom.

[Robh3606]

Pssst

That's not extension it's a peak in the response that tops out at 8k. The roll off is still there. Take a look at this.

http://www.lansingheritage.org/image...4331/page2.jpg

http://www.lansingheritage.org/image...4333/page3.jpg

Look similar???

Rob

[Zilch]

Look similar???

Yup, but I'm talkin' about 12 to 20 kHz here, where 4331(A) dies.

Can't say I much like the peak. If it stays there after breakin, I'll notch it flat. It seems symmetrical, and thus easily "handled." I'd very much like to use this driver, diaphragm, horn, crossover combination. Not sure which LF yet, tho. LE14H-3 may be the better choice, but the B380 "Lowboy" is a kinda cool setup.

I was expecting the HF extension might be damped out with the diamond surround aluminum diaphragm. We already saw that the original tangential surround LE85's had a little bit more (and also sounded better) than the titanium 2426's. It's still there with these....

What's delicious is the way they sound, of course....

[Robh3606]

"I was expecting the HF extension might be damped out with the diamond surround aluminum diaphragm."

The RGA shown with the 4331 is the original aluminum diaphram. The extension you see in your display is from the diamond surround. That surround type extended the UHF response beyond what the original 2420 could do. Same with the 2440 vs. 2441.

http://audioheritage.csdco.com/vbull...ead.php?t=4410

Check out figure 4 2440/2441/Tad comparison

Also B Secondary Resonances on the same page.

Rob

[Zilch]

Thanks, Rob.

It's all GOOD then.

We'll let our new pal CLIO handle the peak....

[Zilch]

2235H's back from reconing by Audivex, here mounted in 5 cuft. JBL 4507 boxes. Closing off two of the four ports as shown retunes them to 27.5 Hz (black). For punchier but less extended bass, just one port closed tunes the system to 33 Hz (orchid). Curves cross at 33.76 Hz, -4.15 dB.

2352 90° x 50° horns with flange modified to accept 2435HPL 3" beryllium diaphragm drivers get a slight downward tilt. They should be moved forward for optimum time alignment, but I'm not yet ready to drill mounting holes in the cabinets.

Crossovers are developmental modification of AM6212, 1 kHz.

What are the woofer frames? Only Zilch's reconer knows for sure.

May be some 4430's for sale here soon....