Digital crossovers vs electrical crossover? (DIY newbie) (1 Viewer)

[Ryan Peddle]

I am currently taking Electronic Engineering in college and learning a lot about circuit board production. Now I believe (an correct me if I am wrong) most people, when building a speaker, use electrical crossovers in their speakers. But has anyone built digital ones one here. I am learning a lot about digi's in school and have 24 hour acces to the school digital production facilities.
What are some of the differences in building electrical crossovers or going with a circuit board digital crossover.
???
Thanks in advance,
RyanP
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[Patrick Sun]

Ryan, do you mean active vs. passive crossovers?
Active crossovers require a power source, DSP chip, and other components, no? The active crossover is constantly monitoring the speaker input signal and deciding which driver should get the signals.
Passive crossover just require the L/C/R components configured in the right configuration and then connected to the driver components. Passive crossover mainly block off certain frequencies from going to other drivers (provided the slopes are designed so there is not hideous bump or null in the crossover regions).
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[JohanK]

Hi Ryan. I would think electrical crossovers (either active or passive) are easier to make than a digital one. Don't digital crossovers need software? This might be the major stumbling block.
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[Kevin Kloet]

no software required for active crossovers....
just a matter of logic gates. They are probably easier (in theory) then passive crossovers... because they don't need tweaking (or not NEARLY as much).... they should perform very close to the design.
Passive crossovers are just easier for people who don't understand a lot about electronics and can be wired by completely inexperienced people.
When you get into REALLY high end caps.... the benefit of passive crossovers (acoustically) may start to kick in.... but I'll be damned if I'm paying $20 for a capacitor.

 

[JohanK]

no software required for active crossovers....

I was talking about digital crossovers such as the ones located in DSP engines in HT processors.
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[Kevin Kloet]

An active crossover IS a digital crossover.... and there is NO software required. It's just logic burned into the processing chip(s).
Does that clarify anything?

 

[TerryC]

Kevin,
I think you are mistaking an Active for a Digital.
Passive-Uses coils, inductors and resistors and located after the amps and un powered
Active-uses samll op-amps, capacitors, and resistors, located before the amp and needs its own power supply
Digital-Burned on a chip like you mentioned. But used software to make the parameters that is burned into its firmware. Located before the amp and needs power
Terry

 

[JohanK]

Terry eloquently stated what I was trying to clarify.
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[Kevin Kloet]

Sweet, thanks for clearing that up.
Of course, software is required (and a station that can burn in the chips) if you want to use PLDs... but if you just wire into gates in predetermined ICs... you won't require software (probably a few more chips though).
I thought he was refering to software just to run the chips, anyway.
I thought you could speak of active and digital crossovers in the same breath... even though the operation is different.
I guess that's the draw of active crossovers, as they are analog and can be tweaked on the fly with varistors... why aren't they more common I wonder? Power supplies are cheap.

 

[JohanK]

why aren't they more common I wonder?

I'm not an expert on crossovers but I guess I think they are pretty common...aren't they in most powered subs?
With more HT processors/receivers starting to incorporate flexible x-over controls (including slope and frequency point adjustments), maybe active x-overs will be a thing of the past.
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