Is 6dB active crossover a good choice

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yes i think the question was, is it of any interrest of making you're active crossover 6db rather than 12 or 24 db.

all i can tell you is that as far as i know 6db is not enough in most of the case, excepting if you go 3 or 4 ways with well damped paper drivers.
6db passive has not only the best reputation sound-wise, but also the reputation of being the crossover the most difficult to implement.
Even so lots of people thinks that the drawbacks of 6db slopes are more important than the advantages

Rod at ESP says that a 24/db active xover will eat the 6db passive anyday, because of inherent advantages of active crossovers that will make the drawback of steep slopes less important. from my own experience i tend to agree with him.

i think 6db active is good if you know what you are doing. expect much complexity or much distortion
 
With 6db XOs, drivers need to be very well behaved. If you are do ing digital XOs, you may have a better selection of tuning options to get higher slopes with phase adjustments that will make driver selection less critical to acheive the best performance.
 
noah katz said:
"i think 6db active is good if you know what you are doing. expect much complexity or much distortion"

How complex can you make a 6 dB XO?

Ask Jim Thiel. His speakers are *stuffed* with crossover.

Long story short, either you pick drivers that are flat at least two octaves from the nominal cutoff point (ie a tweeter crossed over at 4 kHz must be flat down to at least 1 kHz), or you equalise them to behave that way. Since few drivers are flat that far away from their usual crossover frequencies, EQ is the method of choice - hence the large passive networks.
 
Hi, thank you very much to all of you taking some time to answer.
My system is all active with 4 way speaker with 4 power amp.
Right now my crossover is set to 150Hz - 600Hz - 3000Hz.I would like to go below 150Hz but missing a lot of bass. 15 inches for bass,
10 inches for midbass, 6 inches for highmid and a tweeter . Would like to crossover at no more than 80Hz - 300Hz - 2500Hz but as soon as I go lower than 150Hz ,missing a lot of bass and dynamic in the music in bass and lowmid..I think 6dB would be easier to build than 24 dB slope and with less components.

Just go to http://www.exquisiteaudio.ca/ on the home page and look for utopia clone by Daniel , this is my 4way speaker.
 
ostie01 said:
HI, would like to know why I could not find multi way 6dB active crossover for home audio. Is it a good idea to spend time building one with the best parts I can find. Many find that 6dB passive crossover is the best choice, why not for active. Thanks.

6dB /octave line-level crossovers are easy to implement using passive components. You don't need op amps. Theoretically you could produce the ultimate system, assuming your drivers are up to the task.
You might find, though, that a combination of line-level passive and high level passive (for response shaping) will give you the best of both worlds.

Have a look here.
http://www.t-linespeakers.org/tech/filters/passiveHLxo.html
 
6db passive filters do create less phase errors than higher slope passive x-over; regarding that active filters do not create phase errors, no need to chose 6db slopes; higher slope active filters will allow you to chose a larger panel of drivers.

Using 1st order filters does indeed put more demand on the drivers and thus the same drivers might not achieve the same SPLs for a desired maximum amount of distortion as if they were used with a higher-order filters. So the minimised phase anomalies come at a price.

But saying that active filters in general would cause less phase errors than passive ones is completely wrong.
The same filter -function/-order generates the same amplitude- and phase- behaviour in either passive or active implementation this is so for mathematical reasons and cannot be overcome.

The only analog* active solution that really minimizes phase-anomalies is a subtractive crossover.

Regards

Charles


* If you go digital there is some more choice, i.e. FIR filters.
 
I don't think the original "phone booth" by Jacques Mahul uses 6 db/octave filters. But since your clone doesn't seem to use the same drivers as the original box does you won't have to take the original crossover into consideration.
One rather has to decide on the actually used driver's properties.

Regards

Charles
 
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