Audiophile active crossover

[Calvin]

Hi

Jay, I totally disagree. Passive filters are way less flexible than active. You have to account for the electrical impedance of the driver. This limits the available range of solutions. Than follows the sourcing of parts. There's hardly an affordable high quality high power pot on the market. Passive technology also is ruled out if You require a high-Q filter. Cascaded stages influence more on each other, while the buffers in active stages isolate the stages. And last, passive filters cost on power efficiciency.
The probs You are talking of are probs related to implementions of the technology, not drawbacks of an technology in itself.
I assume you are talking about the same reasons I critizised. With passive technology probabely no one would design the filter after textbook formulas and add several EQ stages.
No, of course not, because there's no good reason to do so. If just a larger value of a series inductance allows for the baffle step correction, it' d be rightous foolish not to use it.
I don't know where it came from, that the common sense thinking with active crossovers is often put away. But there's no reason to design an active filter not just after the same design principles as an passive filter. A 'integrated solution' as You seem to have named it. I like that term, as it describes exactly the difference between typical active designs where filter functionality and EQ functionality is separated and good active as well as passive designs where filtering and EQing is combined. The separated design leads to more complex circuitry with more parts (OPamp graveyards as we call them over here), cost and effort and it seriously costs on sonic quality. I assume this design principle as the most prominent reason that active systems are rather a niche technology, since it kills most of the possible sonic advantages of active technology. If active doesn't sound better than passive then the designer hasn't done his homework right.

jauu
Calvin

[vacuphile]

Calvin, fully agree, you can only design an active filter well if you know exactly the drivers and the enclosure you are designing it for. In that sense, off the shelve solutions don't work, just like textbook passive filters usually don't work. It may be easier for some to tweek a passive filter, but it is not that hard using active technology. And, you can just do more actively, at lower cost.

[argonrepublic]

There is far more here than I understand. I am a musician that is unsatisfied with the cosumer/pro equipment that is available to me and I am a new electronics student. As much as what I have currently is far better than what I have EVER purchased. Responses to this forum have made it clear that I can get much more out of my speakers. I am using a dynaudio D28/2 with Dynaudio MW160 in a Foccus enclosure. Is anybody willing to deign a crossover for me? It is beyond my knowledge and ability at this time.

[Jay]

Originally Posted by vacuphile

It may be easier for some to tweek a passive filter, but it is not that hard using active technology. And, you can just do more actively, at lower cost.

Exactly. Except when one is not limited to low cost system and performance

[vacuphile]

Jay, it is usually better too, just happens to be cheaper, but that is just how I think about it, based on some experience building speakers of both varieties.

[Jay]

Originally Posted by vacuphile

Jay, it is usually better too, just happens to be cheaper, but that is just how I think about it, based on some experience building speakers of both varieties.

The idea of active crossover is good. It is just that not everyone can accept a series of opamp in the signal path.

[vacuphile]

Jay, I understand the point, but there has always already been a series of opamps in the signal path before it gets to the consumer. Fortunately, they are very good.

[Jay]

Originally Posted by vacuphile

Jay, I understand the point, but there has always already been a series of opamps in the signal path before it gets to the consumer. Fortunately, they are very good.

That is a very common argumentation. But I think there is a flaw in the logic.

When a music is recorded with many opamps (during mixing), it doesn't mean that there will be no problem when the music is reproduced with opamps for the second time.

What can be perceived during listening (e.g. fatigue), not all can be captured in a recorded material.

MP3, FM radio signal, all are far from perfect. But they will sound different through an opamp. Because the problem is not only in the recorded material or the source, but in the reproduction of the material.

[Calvin]

Hi,

It is just that not everyone can accept a series of opamp in the signal path.

Right And that´s why we can easily replace OPamps by simple discrete source followers (Emitter-, cathode-followers) in unity gain SallenKey filters which allow for music not just replay

Put all things together active is not necessarily cheaper, but rather costier, since it means more effort regarding power supply number count, numbers of amplifiers etc. It is just that in tendency there are less boutique parts around which often cost incredibly much more, but still can´t keep up with the small sized lowvoltage devices required for active technology.

jauu
Calvin

[IMSTOOPID]

somebody forgot about the increased dynamics of active vs passive..
and not having the parasitic losses of all the passive components between eh amps and drivers..

now since my DIDDEN modified dcx2469 sux so bad.. I'm going back to designing a 4 way analog x/o to mimic the digital.. op amp or discrete.. dunno

probably gonna be a mix and depends on the final filter circuits ..
i'll take active any day over passive. except for cost of all those amplifiers..lol