2405 Alnico to 2403/076 conversion

[Ken Pachkowsky]

Hi all

I will undertake the above next week and wanted directions on how to do the following.

1: Remove the label off the back of the drivers with ruining them.
2: Remove the 2405 diffraction lens and replace with the 076 lens without screwing up the diaphragms.

Any tips would be greatly appreciated. I understand one can really screw the pooch doing this.

Ken

[johnaec]

1: Remove the label off the back of the drivers with ruining them.

Easy, just rip 'em right off! Or did you mean without ruining them?

John

[Mr. Widget]

2: Remove the 2405 diffraction lens and replace with the 076 lens without screwing up the diaphragms.

After screwing up the foilcals just follow Zilch's advice on handling the soldering iron.

Alternatively use a heat gun to soften the glue on the foilcal and carefully remove it.

As for the diaphragm replacement. Remove the horn first, then hold the wedge with the palm of your hand as you unscrew it from the rear. Take care not to let it twist as it can crease your 2405 diaphragm. Once removed unsolder it. Remove and replace with the 2403 diaphragm. Solder it and hold it in place with the 2403 cone and center it with an oscillator and partially tighten the cone. Check it for buzzing by sweeping the tone. If you are happy with it, tighten it down, again taking care not to let the cone twist. Assemble the horn and test again.

It is fussier than a standard driver.

Widget