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Multiway speaker advantage?

RDoc

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When I added a subwoofer to my audio setup, something we noticed was how much better the midrange and highs were (in addition to the bass). There seems to be received wisdom that limiting the bandwidth of a speaker helps it sound better. I presume this would be because there is less non-linearity in the speaker caused by less physical and electromagnetic interactions between the frequencies.

Does anyone have some information on this? For example, would a 3 way speaker plus subwoofer (4 channels total) sound better than a 2 way if the 3 way had 2 identical midranges, but fed with different frequency bands, e.g. 20-80 for the subwoofer, 80 - 2K for midrange A, 2K - 6K for midrange B, and >6K for the tweeter or something similar? The 2 way for comparison would have something like 80 - 6K for the midrange and >6K for the tweeter or something similar. My question isn't about specific crossover frequencies, it's whether splitting the bandwidth to the drivers would improve the overall sound.

I'm assuming all active channels with DSP crossover, so for a complete system, 1 subwoofer, 2 speaker boxes each with 1 tweeter and 2 midranges, 7 amplifiers and dsp's for all the crossovers.
 

Jdunk54nl

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A couple things COULD be happening,
One you freed up some power on your speakers by adding subs and crossing them higher. Lower frequencies are the ones that use and need the most power. This could allow for better dynamic range on he frequencies the speaker is now playing by not putting the amp into clipping and adding a bunch of distortion.


As far as crossovers, this picture may help (From Toole's Book)
Directivity of speakers.jpg

This is the same information a above, just with numbers.

Speaker Beaming.png
 

Tangband

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When I added a subwoofer to my audio setup, something we noticed was how much better the midrange and highs were (in addition to the bass). There seems to be received wisdom that limiting the bandwidth of a speaker helps it sound better. I presume this would be because there is less non-linearity in the speaker caused by less physical and electromagnetic interactions between the frequencies.

Does anyone have some information on this? For example, would a 3 way speaker plus subwoofer (4 channels total) sound better than a 2 way if the 3 way had 2 identical midranges, but fed with different frequency bands, e.g. 20-80 for the subwoofer, 80 - 2K for midrange A, 2K - 6K for midrange B, and >6K for the tweeter or something similar? The 2 way for comparison would have something like 80 - 6K for the midrange and >6K for the tweeter or something similar. My question isn't about specific crossover frequencies, it's whether splitting the bandwidth to the drivers would improve the overall sound.

I'm assuming all active channels with DSP crossover, so for a complete system, 1 subwoofer, 2 speaker boxes each with 1 tweeter and 2 midranges, 7 amplifiers and dsp's for all the crossovers.
Answer is yes.
A four way active loudspeaker is probably a very good solution , doing it right will sound much better than any 2-way.

A big floorstander: A 12 inch subwoofer 20-80 Hz , a 6 1/2 midbass from 80 Hz to the baffle step at 500 Hz , a 3 inch midrange from 500 Hz to 3,5 KHz , a 0,75 inch dometweeter from 3,5 KHz to 30000 KHz .

You dont have to compromise much if using 24 dB/ linkwitz Riley DSP crossovers and the IMD gonna be low if the drivers are good.:). tpa 3255 amps used.
No waveguide needed.
 
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abdo123

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A four way active loudspeaker is probably a very good solution .

A big floorstander: A 12 inch subwoofer 20-80 Hz , a 6 1/2 midbass from 80 Hz to the baffle step at 500 Hz , a 3 inch midrange from 500 Hz to 3,5 KHz , a 0,75 inch dometweeter from 3,5 KHz to 30000 KHz .

You dont have to compromise much if using 24 dB/ linkwitz Riley DSP crossovers and the IMD gonna be low if the drivers are good.:). tpa 3255 amps used.
No waveguide needed.
baffle width? distances between the drivers?

sounds too easy since literally no one except Revel is getting it right (for the Hi-Fi market).
 

Tangband

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baffle width? distances between the drivers?

sounds too easy since literally no one except Revel is getting it right (for the Hi-Fi market).
The Revels top models are very good examples of 3 or 4 way speakers.

How many loudspeaker constructors do you think compensate for the baffle step loss ?
This is very basic things to get right , and a 3 or 4 inch midwoofer/midrange in a four way loudspeaker is almost optimal if :

1 .The baffle width are right
2. The crossover frequency is right
3. The sensitivity is right ( if its a passive loudspeaker ) .
4. Try mounting the drivers within 1/4 of a wavelength distance at the crossover frequency , using active dsp 24dB/oct linkwitz Riley filtering.

Troel Gravesen has a good formula for counting the baffle step frequency :

” Any driver mounted on a baffle will have an f3 = 11,600/width of baffle in cm. A driver mounted on a baffle of 20 cm with will be down 3 dB at 11,600/20 = 580 Hz. Making the baffle 50 cm wide the f3 is reduced to 232 Hz. Enough for a midrange driver working from 300-400 Hz to release its full potential without baffle step compensation.”

Ofcourse one also has to have a good measurement microphone and computer-program and the skills.
 
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