Why HiFi manufacturers don't make active crossovers anymore?

You absolutely need to start doing and stop thinking. 

Grab a minidsp and a pair of stereo amps and see if you can make a working stereo pair.

Bryston still lists a crossover on their website.

1 -

If you put a high pass (HP) filter in front of an amp, it no longer has to play bass.
Bass is responsible for most of the amplitude variations in a signal.Amplifiers are all voltage limited. That is, they can play up to +- n V
Say n is 20 Volts. If bass takes 15 V, then you only have 5 V left for mid and treble.

Put a HP filter in front of it and now the entire voltage +- 20 V is available for mids and treble.

2 -

Most multiway speakers have resistors in front of the mid and/or tweeter driver to keep the levels similar.

These resistors waste power as heat. A necessary evil in passive crossovers.

Put an active crossover, and amp with adjustable levels and the resistors have no use anymore. No power wasted as heat = higher efficiency

Hey Cosmic,


You are right. That design stinks. He's using multiple amps, but lacks active crossovers.

He's missing a number of benefits going fully active:

- Limited voltage swing to each amp, increasing dynamic of the entire system

- Enhanced efficiency due to removal of any built in padding.

Adding 1 more stereo amp, and going to fully active DSP crossover would simplify things a great deal.

Actual speaker crossovers are complicated.


If you are going to replace a speaker's internal crossover with an external you are going to have replicate the entire transfer function, not just the crossover location and slopes. DSP makes this a lot easier to accomplish.


If on the other hand you are just adding a sub to the bottom end, an analog crossover can do what you need.

The best crossover is a high grade capacitor to roll off the bass going into the mid/high.

If you are going to go with multiple amps, or a satellite/sub, this is a really good compromise. No more parts, or power supplies, at the expense of only having a 6 db/octave rolloff.

If you use sealed (or plugged ported) speakers you can increase your speaker's dynamic range, improve your power handling somewhat as well.
I have a Luxman integrated that lets me separate the pre from the main amp and I'm thinking about doing exactly this.

Hi @closenplay

Very interesting combination of features!!

Is it a traditional enclosure otherwise, or open baffle??
Best,
E

Hi  @audiorusty,

Can you tell us more about your crossover use? It sounds like you are doing more of a satellite/subwoofer setup than a 3-way, is that right?

Are you also using it for EQ?

I should point out, btw, that active crossovers were never a very popular thing. The advent of Home Theater probably did more to create this market than anything else though, when we consider that every HT receiver with bass management has an active crossover built in.

Best,
E

@kenjit

You never asked me anything. I am asking you again, you claim to love DIY and active crossovers.

Show us what you've made and where your experience come from.

Erik

@kenjit

Because none of us have any idea what your perspective is. You claim to love DIY, and active crossovers. OK, show us exactly what you built.  The question of what other speakers you have heard which you like will give us all an idea of your musical tastes and the type of results you are trying to achieve.


After I shared the exact build you complained I didn’t have measurements. Then I showed you where they were. Still, no reply to my question of what you built or listen to.


My perspective, what I like, what I built and what the results were are all out there, and that helps others judge where they might be relative to my tastes. Kind of like knowing you like Evil Dead 2 as the best movie ever. That helps others judge where your own movie tastes are.


Making blanket pronouncements about technology, some things which are dead wrong, repeatedly, and failing to listen, combined with your lack of willingness to share your starting place makes you a lot less persuasive.



Best,


E

I should also point out that horns are one area where active crossovers seem to be used much more frequently and with less fussing.

Its false that active and passive are comparable in difficulty of use.

Hey @Kenjit,

Still waiting on you to answer any of my questions about your current system, what commercial speakers you like, and what you don't like.

You were pretty demanding when I offered to discuss my own system, and failed to return the courtesy. It would help all of us understand where you are coming from.


Thanks,

Erik

miniDSP will get you there.

The thing most amateurs don't get about crossover design is that active or passive, it's more complicated than you think.

Active saves you a lot of part buying, but there are usually some trade offs, like 3x more amplifier channels, and a lot more parts that go between the singal and the driver.

I'm not against active crossovers at all, but the main advantage pro's like them for, better power efficiency and dynamic range, are not really issues the same way for home enthusiasts. 

Here's an article that describes a lot of what a crossover must do, to give you an idea.
https://speakermakersjourney.blogspot.com/2016/12/crossover-basics-driver-response.html
This only covers a few points. What's still missing is phase matching and baffle step equalization. All doable in an active setup, just saying, there's a lot to do.