Why HiFi manufacturers don't make active crossovers anymore?

Not true I’m afraid - it will be impossible for any passive crossover or indeed driver to be absolutely time and phase coherent across every frequency. Some of the high end digital algorithms do achieve that.

I have experience of ’correcting’ Shahinians, JBLs, B&Ws & Royds and in every case the change was very apparent & positive.

Some months ago I also did a ’quick & dirty’ crossover and speaker calibration to some Mission floorstanders for another forum member (prior to him using MiniDSP). We were both shocked by the huge uplift in coherence, smoothness, imaging and overall clarity achieved vs the original uncorrected and passive crossovers.

I’m not trying to be controversial so apologies it that appears too blunt.

I would like to know more analog crossovers similar to this models from Fostex, EN3000 and EN3020, EN3000 appears regularly to sell in Japan, the more sophisticated one EN3020 it's much more hard to find...

Anyway, would like to know more units with similar characteristics like this ones, very straight forward 3 way, easy to use.

For those who not know this Fostex, here they are:

EN3000: https://www.hifido.co.jp/sold/14-84210-27250-00.html
EN3020: https://www.hifido.co.jp/sold/11-62786-28291-00.html?LNG=E

Thanks.

No DSP's recommendations please.

I think the ideal way to do active would be using the built in DSP and crossover function built into server software like JRiver.

It would require multiple or multi channel DAC, but it seems the least destructive method since no additional DA or AD conversions would be needed.

Has anyone experimented with this method?

I have dreamed of modding my TAD CR1's to work with an active crossover,  but I would not want to risk damaging such an exotic driver.

The other issue is I would want not to use amps of a lesser quality than my BHK 300's (with their tube input stage) and could not afford another 2 or 4 channels of BHK.  I have read about people trading their Pass amps for BHK 300's (perhaps because of the tubes)   Maybe a pair or 3 of the stereo BHK 250 would work.  They are doing a more powerful version, unfortunately not a lower power version for multi ways which would be ideal.  

Would like to know more active analog crossovers similar to this ones, in specs, and layout functionality, anyone have more recommendations?

No DSP please.

Fostex EN-3000

https://audio-heritage.jp/FOSTEX/etc/en3000.html

Pictures: https://www.hifido.co.jp/sold/17-11127-51780-00.html?LNG=E

Specs:

Model Channel divider
Specifications 2-3way electronic dividing network
Bandpass characteristic 18dB / oct
Input impedance 47kΩ
Input sensitivity 0.5V (rated output)
Rated output 1V (Low: 100Hz, Mid: 1kHz, High: 10kHz)
Maximum output 8V (+ 18dB / dBV, distortion 0.05% or less)
Output impedance 470Ω
Total harmonic distortion 0.005% or less (rated output)
Crossover frequency 2way-1: 500, 650, 800, 1.2kHz
2way-2: 2k, 3k, 5k, 8kHz
3way: 500, 650, 800, 1.2kHz (Low / Mid)
2k, 3k, 5k, 8kHz (Mid / High)
Output phase switching 0 °, 180 ° (Low, Mid, High)
S / N 100dB or more (IHF-A)
Input / output terminal RCA pin terminal (pure gold plating)
Power supply AC100V
Power consumption 4.3W
Dimensions Width 482x Height 44x Depth 235mm (19 "/ 1U Standard Rack Mount Size)
Weight 3.5kg

Fostex EN-3020 

Pictures and specs:

http://www.audiocostruzioni.com/r_s/accessori/fostex-an3020-crossower/fostex-en3020.htm

Manual available here:

https://www.fostexinternational.com/docs/tech_support/manuals.shtml

Thanks.

Great discussion!! You guys sent me looking through some of my older gear and i dug up a Pioneer Series 20 D 23 4 way crossover I bought years ago. My thinking then was to construct a speaker system using Kenwood LO-7M amps for the subs and 3 other tube amps for the remainder of the drivers. The tube amp I had in mind for the top end was one of those small Cary triodes that I had read glowing reports of. I still don't have one, but I have everything else except the drivers. This, or something similar to this is where I interpreted @cosmicjazz was headed with his 6 channel amp. With an approach like this it frees you up from all of the constraints of conventional speaker design. I could be all wet with that statement, and am looking for some feedback from Erik and everyone else.
If you had a sweet stereo tube amp to drive a pair of drivers for the mid- highs, another for the mids, and another for the top ends, what drivers would you choose? And something within reason....no $1000 drivers or horns need apply, just bought off the shelf stuff that you think sounds great! And a lot of this is inspired by the Linkowitz designs.