Peerless KD120WFX 12" 8 ohm Speaker ???

[farmerjack61]

Hi there Moondog, foggy weather down here for the last few days and the rain has been welcome.

Mate, I think you are right, in fact I drew up an enclosure last night, see below.

I have a few options for mids; an open frame 6.5" woofer (too much hassel I think as it will require more joinery), A jaycar CM2085 polycone, or CM2090 1.5" domie. The latter has some limitations I think, so I reckon I will go with the old-fashion CM2085 sealed unit which is rated at 95db so I will put a 1.5db cut on that also.

There are a few options for the high frequencies, including a CT2010 1" dome, a pair of 8r foster titanium domes in paralell (with the assosciated impedance drop at hf) or my preferred option of a pair of 4r vifa ring radiators XT25SC90-04 in series to give the finished speaker a minimum impedance of around 7 Ohms across the entire spectrum. The vifa's are rated at about 90db so a pair will make their presence felt.

At the moment I am thinking about a second order Xover all the way through from ~ 800Hz to 4kHz. That is a low pass for the woofer, bandpass for the middie and high pass for the tweeter. I am thinking about reversing the polarity of the signal to bring the whole caboose back into phase.

Have a good day.

[Moondog55]

What ever you do, don't use that POS sealed back jaycar mid.
That Jaycar tweeter is actually OK if you cross it around 3k tho and I would keep to single tweeter.
What's the 6.5 inch??
First of the Autumn rains are early and starting to put some of the Alpine fires out

[farmerjack61]

In reply to VaNarn. How do you do?

I am not interested in talking too much about t&s parameters Van. But I will explain how I came up with those figures.

I used my calculator, a good voltmeter and a good frequency counter and a couple of resistors. Rod Elliotts (esp) DIY site offered a helpful article on the methods and procedure. I can recommend it to all speaker enthusiasts, because it puts the back-yarder in the design engineers seat. This seems to upset a few would-be engineers for some reason? I mean, some arrogant individuals just label people like me - who present interesting information - that is a little out of the ordinary, as"Misinformed". I believe my procedure has full integrity in this respect.

If you would like to help me out, then read the entire post; go back to the second thread & you will read my comments on the accuracy of my own measurements. I am genuine and the results are actual.

I can assure all of you naysayers that I have a good pair of speakers here and that the t&s parameters that I calculated were as accurate as I could obtain with careful procedure and good instrumentation.

But the topic has moved on now. I am in the process of cabinetmaking what are potentially the best set of speakers I have ever owned.

All the best from Tassie.