World's your oyster at crossover frequencies like that (I tend to prefer crossing < 1.5KHz in 2-ways). As far as tweeters go, if you don't want to be spending too much, SB's SB26CDC or its aluminium SB26ADC sister model (there's zero practical difference between them other than looks) are excellent, albeit not the highest sensitivity units that ever graced the Earth. Seas's 22TAF/G, 27TBC/G & 27TBFC/G are still excellent. If you want soft-dome, I'd probably lean toward Scan's 9130, which is a bit of a sleeper -it's the old Peerless HDS, which was supposed to be a high-end model; Scan designed it for them & inherited it when the companies split. It didn't fit into their higher price Revelator or Illuminator model ranges, so ended up lurking at the top end of their entry-level Discovery models. It can't get very low, so I don't use it much myself, but if crossed higher, it's a good one. Moving up a price notch, the SB Satori TW29R-B is one of my go-to soft-dome units -to do better, you really need to be spending twice as much (minimum).
Hmm, sqrt(2500 - 20,000) = ~7071 Hz
driver effective dia. = ~34400/pi/7071 = 1.55 cm/0.61", so ideally a horn loaded, tiny VC super-tweeter or tiny VC tweeter sized/designed for a ~ -35 dB @ sqrt(2500*7071) = ~4204 Hz mean
eff. dia. = 34400/pi/4204 = 2.6 cm/1" dia. = compression horn driver
In short, hard to get around some 'flavor' of horn loading to do it right, so at this point one is stuck with buying based on cost, power handling and EQ to suit with mobile audio components historically the best bang/buck.
This is a trip down memory lane!
FYI, the KEF Chorale crossover had a 6.4 ohm resistance built into the shunt LC in the bass section and thus was not too deep a notch.
It was designed to correct a certain wonkiness in bextrene cones.
You could use a regular coil and add 5-6 ohms.
I'm not wading through this very muddled thread but you may be interested:
https://www.diyaudio.com/community/threads/goodmans-minister.205387/#post-3063836
That's a 3 kHz crossover so I think your Vifa D19 TD 3/4" polydome substitute will be fine.
It's very like the SEAS 19TFF in construction and behaviour and around 88dB I'd guess..
I would use 4.7uF and 15uF and 1mH and 2mH here for ease of purchase.
You might want to add a little attenuation with ceramic 3W 2.2R or so in front of the tweeter section.
Best Regards, Steve in Portsmouth UK.
FYI, the KEF Chorale crossover had a 6.4 ohm resistance built into the shunt LC in the bass section and thus was not too deep a notch.
It was designed to correct a certain wonkiness in bextrene cones.
You could use a regular coil and add 5-6 ohms.
I'm not wading through this very muddled thread but you may be interested:
https://www.diyaudio.com/community/threads/goodmans-minister.205387/#post-3063836
That's a 3 kHz crossover so I think your Vifa D19 TD 3/4" polydome substitute will be fine.
It's very like the SEAS 19TFF in construction and behaviour and around 88dB I'd guess..
I would use 4.7uF and 15uF and 1mH and 2mH here for ease of purchase.
You might want to add a little attenuation with ceramic 3W 2.2R or so in front of the tweeter section.
Best Regards, Steve in Portsmouth UK.
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Thanks Steve - I was hoping you'd come in on this. I used the D19 on your recommendation, but anyway I have it in my Mission 761s and like the crisp and clean highs. It was a very popular tweeter choice for the era and for good reason.