I had another look at the sim, and I think you should buy a pair of 7W 6.2R, 10R and 15R wirewounds at Maplin. 10W types 5cm long, 7W are 3.5cm.
Looks easy to fit a resistor on front of the filter and 15R shunt across the tweeter.
So either 6.2R or 10R in front of the filter will get level right IMO. I'd start with 10R here with a little 5" bass. Tough as old boots, wirewounds, you won't damage them with heat.
Don't be afraid to drill a couple of holes in the tracks and scrape off the enamel either.
Looks easy to fit a resistor on front of the filter and 15R shunt across the tweeter.
So either 6.2R or 10R in front of the filter will get level right IMO. I'd start with 10R here with a little 5" bass. Tough as old boots, wirewounds, you won't damage them with heat.
Don't be afraid to drill a couple of holes in the tracks and scrape off the enamel either.
The originals look similar to my Castle Conway II tweeters, probably not identical though as mine have clear purple cones. I cut the black cloth covers off 20yrs ago and they reproduce cymbals just the real thing they're that good. Cones have benefits over domes, they're a lot less fussy about cabinet edge reflections as there's much less sound sent sideways.
Well i got them sounding great again!
Steve, idid as you suggested but it was to drastic a reduction. So i decided to get one variable L pad so i could experiment better,, got it matching the original quite well using tones and music, then fitted fixed resistors in both xovers and changed the tweeter in the other one. All now good. Ended up with values of 1R and 37 R after the crossover.
Thanks again for all the input.
Steve, idid as you suggested but it was to drastic a reduction. So i decided to get one variable L pad so i could experiment better,, got it matching the original quite well using tones and music, then fitted fixed resistors in both xovers and changed the tweeter in the other one. All now good. Ended up with values of 1R and 37 R after the crossover.
Thanks again for all the input.
Well done, bikelectro! That was a fun project! Thanks for the feedback too. Always good to hear how it turns out. TBH, I've yet to have a disaster here. 
It wouldn't have sounded the same at all with some old dome tweeter.
I'm really quite surprised you got away with a mere 2dB of attenuation here, but trust your ears and taste. Nice.
It wouldn't have sounded the same at all with some old dome tweeter.
I'm really quite surprised you got away with a mere 2dB of attenuation here, but trust your ears and taste. Nice.
You can PM me anytime, vova. It's an open system.
I was pretty rubbish on guessing what attenuation was required for a new Monacor HT-22 cone tweeter. But it worked. Just add the 2.2R really.
Your Castle Durham 3 look like 94mm 3/4" soft domes. Usually 88dB loudness. An easy replacement: Seas 19TFF1 H0737-08 Tweeter - Celestion HF2000 replacement
Probably no adjustment needed. If old tweeters have stopped working, it can be just dried up ferrofluid gone solid or a dry joint in the wiring. Measure a tweeter with a multiumeter and it should read about 5 ohms if fixable. You can also connect a penlight 1.5V battery and listen for a crackle.
I was pretty rubbish on guessing what attenuation was required for a new Monacor HT-22 cone tweeter. But it worked. Just add the 2.2R really.
Your Castle Durham 3 look like 94mm 3/4" soft domes. Usually 88dB loudness. An easy replacement: Seas 19TFF1 H0737-08 Tweeter - Celestion HF2000 replacement
Probably no adjustment needed. If old tweeters have stopped working, it can be just dried up ferrofluid gone solid or a dry joint in the wiring. Measure a tweeter with a multiumeter and it should read about 5 ohms if fixable. You can also connect a penlight 1.5V battery and listen for a crackle.
Dear Steve, this is the layout and appearance of my filter. Section in some sites write 3000 Hz in some 5000 Hz. I do not know the resistance of the WOOFER is probably 4 Ohms. I want to change the coils to tape but do not know their denominations. On forums in Russia Castle there is no. If you can tell me. Sorry for the translation.
vova1968 said:
8 ohm nominal drivers you'd think. It's probably 1.5mH or thereabout on the bass filter for 3kHz crossover with 6.8uF.The tweeter coil might be 0.22mH with 4.7uF.
All guesswork! But 1.5mH coil won't be far off. Don't expect to much change with a tape coil. But better than ferrite I expect. I would think the tweeter coil is an aircoil, so hard to improve.
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