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Why aren't electronic crossovers more popular?

Dion_Sinewave

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They sell 50W power resisters in 8 ohm.
I have protective capacitors already on each one! Supplied ($100each AUD) from me speaker manufacture. And a digital high pass filter/ brick wall linear phase crossover too!

I thought they were supposed to protect my tweeters and also be a high pass filter? They did absolutely nothing..

I should post a photo of them so that much more knowledgeable folks can determine what they’re intended to do.
 

Dion_Sinewave

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This is what I have:
 

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Holmz

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I have protective capacitors already on each one! Supplied ($100each AUD) from me speaker manufacture. And a digital high pass filter/ brick wall linear phase crossover too!

I thought they were supposed to protect my tweeters and also be a high pass filter? They did absolutely nothing..

I should post a photo of them so that much more knowledgeable folks can determine what they’re intended to do.

I meant to use the resistors in place of the speakers while testing and measuring things… like making sure that the woofer amp is not being presented to the tweeter.
 

gene_stl

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I have a DIY tri-amp system and it is a lot of fun and sounds good and gives me lots of things to play with and upgrade. If you are going to go DSP crossovers I would recomend a PC as most stand alone processors like a mini DSP will run out of processing power for crossovers and room EQ. I use analog active crossovers and Rephase / REW for fine tuning FR and rooms EQ but if I was starting over I would go full DSP as it is much more flexable. Regarding caps to protect the tweeter I decided not to and for 10 years have not had an issue. My reasoning is that a good quality cap big enough to offer reliable protection is fairly expensive and will cause phase issues and tweeters arent that expensive. To me a "clean" signal path from amp to driver is one of the main reasons to tri-amp. Other reasonable people will disagree. In any case have fun.
My tweeters and midranges are expensive and have become irreplaceable unobtainium. Correctly sized protection caps in series do nothing to the phase and if they did you probably couldn't hear it.

Even if they were less expensive and easier to obtain and replace I would protect them. Amplifiers don't fail frequently but they do fail.

I use an analog electronic crossover because that is what I have had since the seventies. I am intrigued by dsp systems but I am concerned
that if they have a software / memory sneeze they might send full range to the tweeters or mid ranges. If I ever did switch to dsp there would be double protection for certain. I spend a lot of my day job time replacing digital control boards that have failed for no good reason whatsoever.
 
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Holmz

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My tweeters and midranges are expensive and have become irreplaceable unobtainium. Correctly sized protection caps in series do nothing to the phase and if they did you probably couldn't hear it.

Why would one care about the phase if they were using FIR DSP?

(They would just rotate it back to zero digitally, and do any amplitude while they were at it. )
 

levimax

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Why would one care about the phase if they were using FIR DSP?

(They would just rotate it back to zero digitally, and do any amplitude while they were at it. )
That's one way to look it. Another way to look at it is why would anyone purposefully degrade a direct connection between amp and driver with a cap that costs as much as the driver you are trying to protect and then try to measure the degradation and then add DSP to try to undo some of the degradation when the cap only protects against one of many possibly faults all of which are very low probably if you pay attention to and maintain your equipment. For "unobtanium" drivers it makes some sense but it is far from fail safe protection.
 

Holmz

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That's one way to look it. Another way to look at it is why would anyone purposefully degrade a direct connection between amp and driver with a cap that costs as much as the driver you are trying to protect and then try to measure the degradation and then add DSP to try to undo some of the degradation when the cap only protects against one of many possibly faults all of which are very low probably if you pay attention to and maintain your equipment. For "unobtanium" drivers it makes some sense but it is far from fail safe protection.

I‘ll likely use ScanSpeak tweeters. So if the caps cost as much as the drivers, then I’ll just take me chances and skip the cap.
(But I’ll measure and make sure with with resistors first.)
 

levimax

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I‘ll likely use ScanSpeak tweeters. So if the caps cost as much as the drivers, then I’ll just take me chances and skip the cap.
(But I’ll measure and make sure with with resistors first.)
There are a lot of myths surrounding tweeter failures, the most famous being that larger amps protect tweeters, here is an interesting article https://sound-au.com/articles/speaker-failure.html. For a tri-amp system one of the best ways to protect the tweeters is to use lower power amps. I have used 25 to 50 watt amps (currently Neurochrome Mod 86) over they years and despite some "accidents" my tweeters survived. I doubt this would be the case if I had 200 watt amps driving the tweeters.
 

Frgirard

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Basically, it's people's ideas of "odds". Driving a speaker with a passive crossover, you have only one amplifier channel per speaker system. Passive crossovers are quite robust, so you have a satisfactory arrangement. Not perfect, but satisfactory.

A 3-way speaker system will require 6 channels of amplification and the line-level crossover. So you just went from 2 possible failure points to seven possible failure points. You can tell people on the street that the electronics are very reliable until you're blue in the face; they just don't like those "odds".

As for boutique speaker designers offering upgraded crossovers that are very expensive ..... you need to prove to yourself that those "upgraded" crossovers are financially worthwhile. After all, for the cost of some of those "boutique" crossovers, you can upgrade to a much, much better speaker system. Jim Taylor
Dynaudio air 20 three ways.
Active between bass and mid.
Passive between mid and high.
 

mSpot

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Why aren't electronic crossovers more popular?
They are in fact very popular in active speakers, which often have electronic crossovers and multiple internal amps.

For passive speakers, it's all about the marketplace. Imagine that you are a speaker manufacturer. What would you have to do to sell a passive speaker that requires an external crossover? You must either offer plug-and-play external electronics, or require the customer to purchase a 3rd party crossover+amp where you can provide instructions to set up the crossover. Customers don't want to deal with separate purchases and setup. You would do better to sell active speakers or traditional passive speakers w/crossover.

Edit: sorry, I didn't notice that this is in the DIY sub-forum
 

Another Bob

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I have not yet decided on a DIY speaker build but it seems that crossovers are the most problematic part of speaker design and performance.

Electronic crossovers are available, relatively inexpensive ($100-200) and are professional grade. Some boutique speaker designers offer "upgraded" crossovers that are sometimes many times more expensive than the actual speaker. The forums are replete with modifications to existing crossovers.

Many popular passive loudspeakers have dual binding posts from the factory.

It doesn't seem that difficult to produce 4, 6 or 8 channel amplifiers with electronic crossovers and DSP in a single box. Heck, home theater receivers are 90% there already.
This has been hinted at in some of the previous posts, but not stated explicitly: you cannot put a "generic" crossover into a system and expect the drivers to sum correctly, although you can get close if you stay well away from the drivers' natural roll-off frequency. (By "well away from" I mean an octave or so, and more if you're using less than 3rd order crossovers.) The reason crossovers are the most problematic part of speaker design is that proper design must account for the phase and frequency response changes of the drivers through the crossover region. All of this is handled for you if you use a software-based system that measures the drivers' individual responses and adjusts the filters accordingly - something like Audiolense, for example. Otherwise, you're in for lots of trial and error.

Also, tweeter protection with a capacitor and possibly a resistor protects from more than amplifier failures and user configuration errors. Small amounts of DC offset and low frequency noise from the amplifier that are no problem at all for woofers, midranges, or full-range systems with passive crossovers can be damaging to fragile tweeters.
 

Dion_Sinewave

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There are a lot of myths surrounding tweeter failures, the most famous being that larger amps protect tweeters, here is an interesting article https://sound-au.com/articles/speaker-failure.html. For a tri-amp system one of the best ways to protect the tweeters is to use lower power amps. I have used 25 to 50 watt amps (currently Neurochrome Mod 86) over they years and despite some "accidents" my tweeters survived. I doubt this would be the case if I had 200 watt amps driving the tweeters.
I have NC400 on each tweeter… maybe I should get Neurochrome pair for high frequency
 

levimax

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I have NC400 on each tweeter… maybe I should get Neurochrome pair for high frequency
Those NC400s will smoke your tweeters instantly if something goes wrong. The Neurochrome Mod 86 is almost ideal for a tweeter amp... super low residual noise and since they are direct coupled with a servo virtually no DC offset.
 

Holmz

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There are a lot of myths surrounding tweeter failures, the most famous being that larger amps protect tweeters, here is an interesting article https://sound-au.com/articles/speaker-failure.html. For a tri-amp system one of the best ways to protect the tweeters is to use lower power amps. I have used 25 to 50 watt amps (currently Neurochrome Mod 86) over they years and despite some "accidents" my tweeters survived. I doubt this would be the case if I had 200 watt amps driving the tweeters.

Yeah I have read that numerous times.

I am considering disposing of the current tube amp and going with class-D, which seem to bottom out at ~100W/ch. So there is a lower bound for maximum power than can be connected to the tweeters.
If I used 8 ohm speakers then that makes the amp appear like 50W/ch (as they are rated 100W at 4 ohm).

I should still probably consider a capacitor, but it will not be multi hundred dollar job.
 

gene_stl

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Please don't bother flaming me because I am not actually looking for advice. I am just mentioning what I intend to do.

In the course of looking around the forum there are three more multi amp users who have mentioned blowing up drivers with DSP crossovers. I was suspicious of them before (because of also non audio experience as scientific equipment repair guy) but I have just run into too too many people who have blown up drivers with them. I will never use a dsp crossover. I recognize all of their numerous advantages and tricks they can do.
But they just sneeze too often and too regularly. Sometimes it's a malfunction, other times it is pilot error (which I am not 100% immune to)

In my opinion. I will stick with analog crossovers. I may play with some DSP but it will stay up stream.

It is definitely difficult to find small power amps suitable for multi amping. Especially if you don't want to use Class D for whatever reason.
I am not particularly a tube aficionado, but in multi amping it might help protect rare drivers. Nice output transformer. In a tweeter channel you wouldn't be able to hear much of the distortion. There is something I might need to rethink.

The sound Australia article is worth reading.
 
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MakeMineVinyl

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I am not particularly a tube aficionado, but in multi amping it might help protect rare drivers. Nice output transformer. In a tweeter channel you wouldn't be able to hear much of the distortion. There is something I might need to rethink.
The problem of potential damage to a delicate compression driver is precisely the reason I use a single ended triode amplifier with little feedback which is only capable of 2.5 watts, but those watts go a long way when the horn/driver has 107dB/w efficiency. Another advantage of an amplifier of this type is that they generally never go into hard clipping, so can't damage a HF driver the way a clipped solid state amplifier can. I don't think you're necessarily any safer with an analog crossover over a DSP one - its the power reaching the driver which does the damage and that can happen with a too-high powered amplifier, and doesn't have much to do with the type of crossover.

For the record, my crossover is analog.
 
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