Design Challenge: 2 way active speaker using bi-amp

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In this forum I did not find someone built complete system of 2 way active speaker using bi-amp yet. If anyone have built such system, please let me know.
Specifications are:
- 2 way (woofer + tweeter)
- active crossover can be any type of filter
- amplifier can be chip amp or discrete amp
- all electronics must be small enough to fit the box enclosure, but do not use SMD parts.

I have finished 2 way active crossover PCB. I use 24 dB Linkwitz-Riley filter. I have not yet decide, what amplifier, speaker, and box enclosure.
 
In this forum I did not find someone built complete system of 2 way active speaker using bi-amp yet.
Didn't search but would be surprised if somebody in this huge Forum didn't do it somewhere.

FWIW even I mentioned my battery powered , biamped "Callejero 30", a small amplifier for busking, so certainly there must be others.

If you already built the crossover, don't know what your power requirements are but I'd suggest a 3 x LM3886 amp; 2 bridged for Bass and 1 straight for mid/highs.

In fact it will be overkill; a smaller one, say an LM1875 or TDA2030/2050 will do, but using 3 same type chips will allow all to run from the same PSU.

FWIW, the amp I mentioned: bridged TDA2005 20W into 3.2 ohms woofer and single TDA2003, 6W into a 4 ohms LeSon tweeter:
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Depending on crossover frequency and the efficiency of tweeter, it can be class A for tweeter and p-p for woofer. I've listened to a setup with such arrangement which has high efficiency horn tweeter (compression driver) covering >500Hz and it sounded sweet.

I think the crossover frequency must be at the end of vocal frequency, say 3000 - 4000 Hz. I will search this kind of woofer that capable play on frequency 60 - 3000 Hz at least.
 
There is something obvious to say
a) Multiamping and splitting frequencies at line level has some sense
from the efficiency POV, it's used ( and useful) for big halls where the drivers are of significant power
b) Doing this at home, at least for a two way, it's a little bit of nonsense...
only if the amplifier(s) have very little power and/or cannot 'pilot' correctly a passive crossover
c) It might not be true, such as the example posted by Fahey : but that is made for producing music, and 'electrified' music incorporates also the sound from the chain as its own character. At home is the same, as the content (music) is defined by the processment ( chain)...but you know...ying-yang, too much Yin or Yang
d) I mean :cheeky: the passive crossover, in this kind of holistic view, is the stage after the electronics and before the trasduction, so it mitigates the coldness of steel and silicium substrate before reaching the..paper ( or poly or others ).

Yesterday I was playing with another F.A.S.T. design from recycled cheap drivers & crossover parts. I've been listening in two days with the woofer ( cheap cheap Sony) sans crossover and a dome tweeter crossed at 5 kHz, then I put in the game a little ( elliptic) driver from Pc speakers, adding a coil
to the woofer and a cap for the little one. Results are much better !
 
I did it a few years ago, and I am very sure that other people have done it, too. It's the pair of small white speakers at right in the photo below:

obj388geo371pg13p13.jpg


Here is a short description of the project:
This is a small, 2-way, active speaker built in to a 5 liter closeout Miller and Kreisel cabinet. The woofer is a Peerless 830527 and the tweeter is the Vifa D26NC55. Bass extension is limited to about 150Hz. The active electronics in each speaker include a 3k Hz LR4 active crossover, baffle step compensation, and dual LM3886 chip amps. Separate internal AC-to-DC power supplies feed the crossover and chip amps. Due to the small size of the cabinet, the transformers were located in separate enclosures and the secondaries routed to the speakers via 3-conductor cable terminated with Neutrik PowerCon hardware.​

I still have these, and they do sound good, so I was a bit lucky with how everything worked out. I brought them to the Burning Amp festival a couple of years ago and did an A/B comparison with some large active speakers I was working on at the time. They sounded very good (using the woofer units of the larger speakers) and can play at quite high volume for such a small speaker, at least down to about 150 Hz. Here's a pic from that day:

Burning_Amp_0.jpg


Here is my advice:

If you want to build a high fidelity active loudspeaker, you must first choose the drivers, build the cabinet and mount the drivers. Then you have to measure the response of the drivers, and determine the acoustic centers. You use this information to design the crossover. If you can not do all of that, the next best approach is to design a "powered" speaker - a speaker with a passive crossover but with a built in amplifier. There are many excellent designs for passive speakers and adding an amplifier is pretty easy.

-Charlie
 
Yes, but the problem is quite the opposite : a woofer can stand full power and full audio band whitin the excursion limits...and the break ups which are rather annoying; the tweeter needs at least a 2nd order filter to prevent horrendous break ups at resonance - well, it depends on the models, acoustic targets....

@ Mr Laub : Have you tried suspending the speakers as I suggested in your frugal-OB-thread.....Was it you ?
 
Highly recommend studying Linkwitz Pluto pages.

One of big take home messages from Linkwitz is getting acoustic centers of drivers within 1/3 wavelength of chosen crossover frequency to achieve most uniform response over radiation pattern.

The above link to Rob Elliot's pages is great resource too.

Charlie Laub's advice is good as well. Starting with drivers, and measured performance mounted as to be used.


miniDSP is very attractive approach.
 
Pretty horrible speakers there at Parallel....
did I deserve it ?? Just for saying that : the process makes the content !
Of course there are many sub-species to be analyzed, and it's for sure
that having enough money to guarantee the same equal paths to the signal from source to ...air in motion ....well, what do the pro-active say ?
B.e.m.f ? put a diode on the cable 😛:cheeky:

BTW I always thought that pro-actives were against passive speakers because they couldn't design a proper crossover -----but that's not even the point !
( because myself not really good in doin' it )
The point is that even if you have perfect integrated bi-tri-quadri channels the problems arise elsewhere
 
picowallspeaker;

The OP has obviously expressed an interest in active speakers.

If you don't have experience based in rational principles of active speaker design, perhaps you have nothing to offer here.

This isn't an invitation to open yet another, (and pointless debate IMO) about passive v active speaker systems.

Your jives about a designer's aptitude in implementing a good speaker are senseless babble.
 
This is about design implementation, not debate of passive or active speaker. If you do not have any idea to implement the design, please do not comment. I believe that passive or active speaker can be good and nice sounding if the design is properly implemented.
But I found several commercial cheap bi-amp active speaker have SQ as good as more expensive active speaker that using passive crossover.
 
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