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Cheap 3 way active speaker design schematic

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bharitta

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dear everybody,

1. i found the 3 way active speaker schematic on internet, schematic as attached file below, on the circuit have not tone control (volume, balance, treble and bass), so please help me to find tone control circuit which the best for this active speaker.
2. is the this active speaker have low cost if i build it?if no please your suggestion or alternative schematic which have similar characteristic?

i am very appreciated and thanks for all your help and suggestion


regards,

bharitta
 

Audioguru

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3 way active speaker

You should use Linkwitz-Riley filters instead of Sallen and Key because Sallen and Key filters produce a +3dB peak at the crossover frequency but Linkwitz-riley filters add perfectly at the crossover frequency.

Good speakers use "baffle-step compensation" in their frequency response.
Look at www.diyaudio.com .
 

bharitta

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Re: 3 way active speaker

dear Audioguru,

could you enclosed your suggestion with schematic or examples./


regards,


Bharitta
 

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3 way active speaker

There are lots of examples of Linkwitz-Riley crossovers and baffle-step correction circuits on the internet.
 

FvM

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Re: 3 way active speaker

When targeting to a low-cost solution, particularly with scratched speaker parts, the said sophisticated crossover concepts may be meaningless. You could rather try to compensate lack of speaker quality with arbitray equalizer characteristics.
 

bharitta

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Re: 3 way active speaker

dear everybody,

thanks for your all suggestion, i will find on internet and will be consider again to build this 3 way schematic.

i am very appreciated for your problem solving.

regards,


bharitta
 

zlatkoMM

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Re: 3 way active speaker

Better build 2 way speaker box is easyier and
less calculation for filters.
 

Audioguru

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Re: 3 way active speaker

Many woofers don't go high enough for a 2-way speaker. Many tweeters don't go low enough for a 2-way speaker.

Here is the schematic for one channel of a good quality 24dB/octave Linkwitz-Riley 3-way active crossover circuit:
 

zlatkoMM

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Re: 3 way active speaker

2 way is best.
 

Audioguru

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Re: 3 way active speaker

The very simple crossover network shown for the two-way speaker requires a woofer that performs smoothly at high frequencies where most woofers have trouble. The tweeter must survive operating at low frequencies that destroy most tweeters.
 

zlatkoMM

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Re: 3 way active speaker

Maby is better this is 3 way pass filter:
 

Audioguru

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Re: 3 way active speaker

Hi Zlat,
An active crossover is much better than a passive one because the resistance of huge coils are not in the circuit and the smaller parts have more accurate tolerances. Each driver can have its own amplifier for much better results.

You have extra resistors to ground that ruin the response.
You show polarized electrolytic capacitors that must never be used. Non-polar electrolytic capacitors are used in cheap speakers but their tolerance is very wide.
Your midrange crossover has very shallow slopes.

Here is a good 3-way 18dB/octave passive crossover network:
 

zlatkoMM

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Re: 3 way active speaker

You forget values of elements?
This is only teoretic???
 

zlatkoMM

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Re: 3 way active speaker

tweeter = 10 W / 8 ohm
mid = 30 W / 8 ohm
woofer = 50 W / 8ohm
how calculate filters values ???

Added after 2 minutes:

By the way how can you build active pass when you for example have
power amplifier 1000W.
 

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Re: 3 way active speaker

The values of the parts for the crossover networks determine the cutoff frequencies. The mid and tweeter might need attenuation to match the level from the woofer. You don't know the sensitivity of the drivers so the speaker that you make probably will not sound correct..

If you don't know what is the manufacturer's recommended cutoff frequencies for your speaker drivers then you can't make a crossover network that will work properly and protect the drivers from damage.

A few speaker drivers are strong enough to be driven at full output from a 1000W amplifier. Speaker drivers with less power rating will be quickly destroyed by 1000W at full output.
 

bharitta

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Re: 3 way active speaker

dear Audioguru,

would you like to send me the circuit 3 way active for right channel, because after i see the your schematic which have "please note" i'm confuse about it.


thanks for your attention and cooperation.

regards,


bharitta
 

zlatkoMM

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Re: 3 way active speaker

hey bharitta
he need product specification like frequency range,impedance,power and other
to noneed stuff,just complicate....
 

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