4430 help!

[Guido]

I prefer this style

Actually its a 3135 clone!
I think it looks more "reliable" than the originals.

[Guido]

The only item in question is L1 with too low DCR. Maybe put a resistor in series with it, 0.06 Ohms? I do find them in surface-mount metal strip and wirewound versions, about $1.50. That's more like a fuse, actually. :

Yeah! series resistor will do it. Or just forget about that as you anyway have the rheostat in series.

[Zilch]

Goodo JOB, Guido. You set a standard for the rest of us.

I have some fiberglass Vectorboard here, so I may build like Rob did. Just gotta find the pins....

Point being, nobody who can handle a soldering iron should feel intimidated about building these themselves.

Yeah! series resistor will do it. Or just forget about that as you anyway have the rheostat in series.

That's what I thought at first, too. But, I looked again, and the rheostat and inductor are separated by the capacitor, so it's not the same.

Best answer is the proper smaller-wire inductor (22 Ga. air core, looks like), of course, but for now, I'll order some of them tiny resistors....

[Edit: Spreadsheet again updated, parts ordered. All in stock except 1.80 mH coil, B/O. I bought the PE 260-274 dual faceplate with 260-252 L-Pads instead, tho, for a little upgrade. ]

Who knows a source for these 0.04 mH inductors? This is the laminate-core version, 20 Ga.:

[Note proprietary "Gob o' Snot" mounting methodology.... ]

[Zilch]

In the context of what these are selling for, DIY is not the most economical route.

BUT, ours're gonna be better!

http://cgi.ebay.com/ws/eBayISAPI.dll...762120683&rd=1

http://cgi.ebay.com/ws/eBayISAPI.dll...757445158&rd=1

Who the Hell is parting out 4435's? Sheesh!!!

I'm not ignoring everyones' suggestions to do the biased version. Just wanna see how doing it straight works, first....

[Mr. Widget]

"Point being, nobody who can handle a soldering iron should feel intimidated about building these themselves."

Sorry to bring it up, but I inferred from your post on the 2403 thread that you can't handle a soldering iron....

Widget

[Zilch]

Nope, soldering's not a problem. It's screwdrivers (and Sawzalls) that get me in trubble....

These, too:

[Zilch]

$20 enclosed rotary switches are higher quality than used in factory crossovers. Actually 6-pole 4-position, simply moving the shaft stop converts them to the 2-position operation we need.

Rated 0.5 A switching and 15 A continuous, they should work fine in this application. That'd be 1800 W across 8 Ohms. It'd take 120 V to do it.

They could also be used to switch other options in and out, as well, though I can't think of any right now.

Our other lead on a switch turned out to be $119 each and a minimum $500 order. Nope.

Having the 6 poles, they could also serve N4333 (6 circuits) and possibly other int/ext switching needs as well.

1.5" across the terminals, 1/4" shaft with knob flat. Low value metal strip resistors, rear:

[Uncle Paul]

Thanks for dogging those rotary switches down

[ricesinice]

Well, thank you guys for getting me on the right path. I ordered a bunch of parts from Parts Express, and wound my own coils (almost to dcr specs!). Finished one and hooked it up, and the sound is better than my own homebrew crossover. I did notice that the speakers sounded, and measured best with pot R201 all the way over to about 1 ohm resistance. So, if you are having a hard time with that part you really might think about using a resistor in place of it.

Now on to building the second crossover!

[4313B]

So, if you are having a hard time with that part you really might think about using a resistor in place of it.

Good point. Those things have sufficient slop in them that a set of fixed 1% resistors might be a nice option. Something like how the straps are on the UHF of a 250Ti. Four levels set at 1 dB or 1/2 dB increments maybe. I believe the S9800 is 3/4 dB increments but I can't remember for sure. Whatever.

[Zilch]

I ordered a bunch of parts from Parts Express, and wound my own coils (almost to dcr specs!).

How about providing us a little tutorial on winding our own inductors, with pics, of course, posted here?

Please also provide recomended types, sizes and sources of wire, coil forms or bobbins, etc.

I did notice that the speakers sounded, and measured best with pot R201 all the way over to about 1 ohm resistance.

Yup, "0" is nearly full on....

Finished one and hooked it up, and the sound is better than my own homebrew crossover.

You musta got the "magic" part right!

[We want PICS!]

[Zilch]

Laying out my DIY N3134's, I have come up with additional options for the two surplus positions on the switch, which derive from work experimenting with various applications of it here:

#1: Passive per original.

#2: Biwire - splits the LF and HF sections without changing out any components. Good for separately driving the two sections with multiple amps. Zilch runs this way with Q=2 bump at 25 Hz on UltraCurve.

#3: Biamp per original. Use external 5235 crossover with 4430/35 cards or other, as desired. Zilchster preferred configuration using 5235 bump filter.

#4: Drivers only - well, not really. Leaves the 20 uF in series with the compression driver for protection against mishaps below 1 kHz (a Zilch exclusive). Bypasses the Zoebel in the LF, tho, per N3135. For users who just MUST exercise their parametric EQ's.

Anybody have other suggestions for this switched options upgrade?

[Ian Mackenzie]

Thanks Rob for demonstrating that the "purpose" for that circuit leg ( in which R202 is located ) - is to "restore balance" to the horns' lower midrange frequencies. This particular frequency range has been severely depressed in the other ( UHF contour ) circuit leg.

Of course, if a person knew their own preference for "midrange balance' - then R202 could be omitted & replaced by either 2 or 3 resistors ( depending on if a person wanted an Lpad or Tpad ).

The actual theory of operation is quite intuitive, particularly if you have a chance to read the white paper on the 44xx published in the early 80's AES.

About two years ago now Robert Hamel an I reverse engineered and tweaked the arse out of these networks to get the desired results with the 2122H / 2123H mid cone , which I might add is impressive at least down in Robert's cellar I thought so! But then again all Robert's diy systems are Fab.

The attached files show my system and the resulting curve....I would love to tweak this network for a Tad 2001 some day. The curve here is that of the DR2425 dia used with the 2420 alinco driver. The network to the 2122H used 3135 crossover which is a special 2nd order filter with minimal group delay, the 2122H (or 2235 ) and the compression driver are " IN PHASE".

I recall publishing a number of graphics in PC paint to explain the action of the variable pots in one of the earlier forums. The effect of the Pad in the 2 khertz area is mid presence, I prefered it nearly up full most of the time, this gives nice holograhic centre image.

However, for those keen enough to build up clones you are best served with an analyser (Gated) to adjust the overall response for a flat curve extending to 16.5 khertz or so.

Ian

[Guido]

Nice calendar Ian

I like the 2344 / 2122 Combo.
Ooops and the 2245 of course.

[Ian Mackenzie]

That's my darling Elle, our super model.

Ian