Rules | Recent posts | topic RSS | Search | Register  | Log in

3 way active speaker

 
Post new topic  Reply to topic    EDAboard.com Forum Index -> Hobby Circuits and Small Projects Problems
Author Message
bharitta



Joined: 01 Oct 2007
Posts: 21


Post07 May 2008 9:02   3 way active speaker

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



Sorry, but you need login in to view this attachment

Back to top
Audioguru



Joined: 19 Jan 2008
Posts: 245
Helped: 16
Location: Canada


Post08 May 2008 2:17   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 .
Back to top
bharitta



Joined: 01 Oct 2007
Posts: 21


Post09 May 2008 2:54   Re: 3 way active speaker

dear Audioguru,

could you enclosed your suggestion with schematic or examples./


regards,


Bharitta
Back to top
Audioguru



Joined: 19 Jan 2008
Posts: 245
Helped: 16
Location: Canada


Post09 May 2008 3:45   3 way active speaker

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



Joined: 22 Jan 2008
Posts: 1759
Helped: 327
Location: Bochum, Germany


Post09 May 2008 8:09   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.
Back to top
bharitta



Joined: 01 Oct 2007
Posts: 21


Post10 May 2008 11:49   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
Back to top
zlatkoMM



Joined: 04 Apr 2008
Posts: 90
Helped: 2
Location: Croatia


Post18 May 2008 16:43   Re: 3 way active speaker

Better build 2 way speaker box is easyier and
less calculation for filters.
Back to top
Audioguru



Joined: 19 Jan 2008
Posts: 245
Helped: 16
Location: Canada


Post18 May 2008 17:03   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:



Sorry, but you need login in to view this attachment

Back to top
zlatkoMM



Joined: 04 Apr 2008
Posts: 90
Helped: 2
Location: Croatia


Post22 May 2008 16:45   Re: 3 way active speaker

2 way is best.


Sorry, but you need login in to view this attachment

Back to top
Audioguru



Joined: 19 Jan 2008
Posts: 245
Helped: 16
Location: Canada


Post22 May 2008 17:27   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.
Back to top
zlatkoMM



Joined: 04 Apr 2008
Posts: 90
Helped: 2
Location: Croatia


Post22 May 2008 20:14   Re: 3 way active speaker

Maby is better this is 3 way pass filter:


Sorry, but you need login in to view this attachment

Back to top
Audioguru



Joined: 19 Jan 2008
Posts: 245
Helped: 16
Location: Canada


Post22 May 2008 21:35   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:



Sorry, but you need login in to view this attachment

Back to top
zlatkoMM



Joined: 04 Apr 2008
Posts: 90
Helped: 2
Location: Croatia


Post23 May 2008 13:03   Re: 3 way active speaker

You forget values of elements?
This is only teoretic???
Back to top
Audioguru



Joined: 19 Jan 2008
Posts: 245
Helped: 16
Location: Canada


Post23 May 2008 16:04   Re: 3 way active speaker

zlatkoMM wrote:
You forget values of elements?
This is only teoretic???

The values of the parts must match the specs for the speaker drivers.
Back to top
zlatkoMM



Joined: 04 Apr 2008
Posts: 90
Helped: 2
Location: Croatia


Post24 May 2008 7:46   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.
Back to top
Audioguru



Joined: 19 Jan 2008
Posts: 245
Helped: 16
Location: Canada


Post24 May 2008 17:28   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.
Back to top
bharitta



Joined: 01 Oct 2007
Posts: 21


Post26 May 2008 7:56   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
Back to top
zlatkoMM



Joined: 04 Apr 2008
Posts: 90
Helped: 2
Location: Croatia


Post26 May 2008 13:47   Re: 3 way active speaker

hey bharitta
he need product specification like frequency range,impedance,power and other
to noneed stuff,just complicate....
Back to top
Post new topic  Reply to topic    EDAboard.com Forum Index -> Hobby Circuits and Small Projects Problems
Page 1 of 1 All times are GMT + 2 Hours


Abuse
Administrator
Moderators
topic RSS 
sitemap