High efficiency (HORN) vs Conventional design

[mbon]

I want to build my ultimate three way DIY pair of speakers and there's two big family :

1-Horn with more than 100dB/w/m efficiency beyond 50 Hz with big bass box tuned for efficiency and no low frequencies
++seems to have great dynamic & lots of micro
details
--bad polar response for home use (horn), coloration and resonances due to horn, bad crossover between cone and compression in frequency range where human hear is very sensible, big box and short bandwith (often lack SPL between 16-50 Hz and over 15kHz)

2-Conventional design with good drivers between 86 & 92 dB/W/m sensitivity
++good polar response, real high fidelity bandwith, 16-35000 Hz is possible with "relative" small boxes, crossover is easier because of the high variety of driver making every configuration possible
--seems to compress music, need strong complex power amplifier



Since I know that for the wanted SPL, cone displacement is the same between high or low efficiency driver, we can conclude that dynamic depend only from power amp, no ?
So low efficiency driver should be as good in dynamic criteria than higher SPL PA drivers ???

So, is high efficiency a real factor to considere ?

[rick57]

depends on the extent that you will build a more powerful amp, for the room and desired SPL, for the less efficient speakers

[baggystevo82]

Hi, Efficiency will be a real factor to consider as it changes what amps you can use to get to the required listening level. As it seems you're yet to decide on the amp/haven't got one yet, I would be inclined to go for high sensitivity/low power amp
Steve

[Hesky]

So low efficiency driver should be as good in dynamic criteria than higher SPL PA drivers ???

yep, if there hooked up to an appropriate amplifier that is.

Hesky

[Josephjcole]

Originally posted by mbon

--bad polar response for home use (horn), coloration and resonances due to horn, bad crossover between cone and compression in frequency range where human hear is very sensible, big box and short bandwith (often lack SPL between 16-50 Hz and over 15kHz)

I'd like to disagree with a couple of these points:
1-coloration and resonances due to horn- the only reason for this is if the horn is designed/built poorly.
2-bad crossover in frequency range where human ear is very senitive- again this is possible but only from poor design... and there is always the option of something like the Oris 150, which would but the crossover out of the way (more or less).

just my two cents worth...

[Greg B]

1-Horn with more than 100dB/w/m efficiency beyond 50 Hz with big bass box tuned for efficiency and no low frequencies
++seems to have great dynamic & lots of micro
details
--bad polar response for home use ...

Most high efficiency horn systems aren't really 100db more like 97 unless you use two 15" drivers. Bass extension depends on box size, I wouldn't say high efficiency means no low frequencies. An F3 or 40-50 is typical, but it's possible to do a little better. All this depends on size limitations, among other things.

Good dynamics and microdetails, yeah. Bad polar response? Not necessarily. Depends what you mean by bad. Controlled directivity is often more helpful than hurtful.

Colorations and resonances - you get these either with a horn or direct radiators, just different types.

The lower crossover point in a typical horn system is at a lower point which is in a less sensitive zone in our hearing. The wavelengths are also much longer, making the crossover easier. I don't buy the 'not sensitive zone' crossover arguments anyway. I can hear a bad crossover wherever it is.

2-Conventional design with good drivers between 86 & 92 dB/W/m sensitivity
++good polar response, real high fidelity bandwith, 16-35000 Hz is ...

Good polar response is relative. If you have a small carpeted apartment, wide dispersion may be better. With a larger room and hard surfaces, tighter dispersion will be better. Reducing room reflections improves imaging. Convential drivers will be easier to get flat frequency response with, no doubt about that.

You will need a SERIOUS subwoofer to get 16 hz with in either case, but of course lower efficiency drivers typically have more bass extension.

How about split the difference and make a system about 94-95 db? You can do this with Focal drivers.

Ultimately, it depends on the music you listen to. Oftentimes rock will sound better with compressed and distorted speakers. For high fidelity for well recorded music, a moderate to high efficiency is required, IMO.


Greg B

[mbon]

Originally posted by Hesky


yep, if there hooked up to an appropriate amplifier that is.

Hesky

anyone thinking that high sensitivity is still the way with big good transistor power amp ?

[mbon]

Originally posted by Greg B


Most high efficiency horn systems aren't really 100db more like 97 unless you use two 15" drivers. Bass extension depends on box size, I wouldn't say high efficiency means no low frequencies. An F3 or 40-50 is typical, but it's possible to do a little better. All this depends on size limitations, among other things.

Absolutely right but bass reach 100 dB sensitivity near 60 Hz wich is a nice contrabass not.

Originally posted by Greg B
Good dynamics and microdetails, yeah. Bad polar response? Not necessarily. Depends what you mean by bad. Controlled directivity is often more helpful than hurtful.

By polar response, I'm talking about sound width and depth and I'm a special fan of dipole configuration since I heard Orion, this thead is about choosing the best way, dipole is also possible with high sensitivity drivers, linkwitz think that with recent power amp, sensitivity is not an issue, what I heard seems to confirm but I don't want to miss something....

Originally posted by Greg B
Colorations and resonances - you get these either with a horn or direct radiators, just different types.

of course, open baffled with direct radiator seems to have some strong arguments about coloration and resonance...

Originally posted by Greg B
The lower crossover point in a typical horn system is at a lower point which is in a less sensitive zone in our hearing. The wavelengths are also much longer, making the crossover easier. I don't buy the 'not sensitive zone' crossover arguments anyway. I can hear a bad crossover wherever it is.

You're talking of something like K2 9800 JBL, a 3'' drivers for midrange, a 1'' drivers for HF, JBL choose 800 Hz for horn cutoff, it seems good for our hear...
I've got a Behringer DCX2496 DSP in his box waiting for my dreamed 3-Way loudspeaker, just want to choose good drivers and enclosure design

Originally posted by Greg B
You will need a SERIOUS subwoofer to get 16 hz with in either case, but of course lower efficiency drivers typically have more bass extension.

I can tell you since I deal with big XMax drivers designed for HT subwoofer application that with a strong amplifier there's no SPL and no low frequencies limits...Of course precision and clarity of sound will ask for more than 18'' drivers in tons of air baffle but I prefer a 16Hz with "fog" and bad harmonics than silence below 30 Hz

Originally posted by Greg B
How about split the difference and make a system about 94-95 db? You can do this with Focal drivers.

Focal is stopping drivers production for DIYers, the best drivers from Focal are not available for years, beylium and best audiom drivers found in Utopia have never been available for DIYers...
This brand has no interest for me for ten years, they keep good technology for their high end products...not to sell

Originally posted by Greg B
Ultimately, it depends on the music you listen to. Oftentimes rock will sound better with compressed and distorted speakers. For high fidelity for well recorded music, a moderate to high efficiency is required, IMO.

Greg B

Why (demonstration please) a low sensitivity system will compress dynamic if power amp can assume ?

I listen every kind of good music to my ear. I play classical piano and love to listen some good electronic music, the best piano I've ever heard was on Orion from SL, but this design lack some micro details to my hear...siegfried seems to think that I've heard to much titanium mid-high and I think he's right, a good speaker just play what is on the tape, no more....

[Greg B]

By polar response, I'm talking about sound width and depth and I'm a special fan of dipole configuration since I heard Orion, this thead is about choosing the best way, dipole is also possible with high sensitivity drivers, linkwitz think that with recent power amp, sensitivity is not an issue, what I heard seems to confirm but I don't want to miss something....

There are some similarities in dipole response and horn response in terms of dispersion. Both are directional. Dipoles require a suitable room, since you have the out of phase waves from the back of the cone entering the room with the same amplitude as the front wave.

AFA sensitivity, I respectfully disagree, based on personal experience. But with decent amplification, it's less of an issue. With SS, lower sensitivity can be better, as the 'first watt' isn't always that great, depending on the amp.

of course, open baffled with direct radiator seems to have some strong arguments about coloration and resonance...

Yes, it works fairly well, especially in the bass. You do have to be careful with the mids/highs, as it can be a bit diffuse.

I've got a Behringer DCX2496 DSP in his box waiting for my dreamed 3-Way loudspeaker, just want to choose good drivers and enclosure design

Cool. That should make things easier. I like a good 3 way.

I prefer a 16Hz with "fog" and bad harmonics than silence below 30 Hz

OK. That's reasonable. I'd still be more inclined to use a separate subwoofer crossed very low than a 3 way with subwoofer drivers as woofers. IMO, you'll lose midbass definition doing this.

Focal is stopping drivers production for DIYers, the best drivers from Focal are not available for years, beylium and best audiom drivers found in Utopia have never been available for DIYers...
This brand has no interest for me for ten years, they keep good technology for their high end products...not to sell

OK. I've heard this rumor, but I don't know if it's true. I bought some Utopia woofers from Zalytron in New York before. The Excel magnesium drivers are very nice. I just was using some last weekend. They are surprisingly low distortion. I do feel that the have a touch less detail resolution than some other drivers I've heard, but very good.

Why (demonstration please) a low sensitivity system will compress dynamic if power amp can assume ?

I don't know, I'm not an engineer. I presume because of the relatively large impedance mismatch with the air compared to conventional hifi drivers.

best piano I've ever heard was on Orion from SL, but this design lack some micro details to my hear...siegfried seems to think that I've heard to much titanium mid-high and I think he's right, a good speaker just play what is on the tape, no more....

To some degree he may be right. Very good speakers should not shout out "I'm detailed" as some hifi speakers do. But as I said before, I don't think the Excels are the most detailed drivers I've heard, though they are very neutral and generally good. For example, the Fostex FE108E sigma is more detailed than the W12 IMHO, but more colored as well. Pick your poison...

Anyway, any number of different approaches can work. It's more important to design well, whatever road you decide to take.

Greg B

[mbon]

Originally posted by Greg B

To some degree he may be right. Very good speakers should not shout out "I'm detailed" as some hifi speakers do. But as I said before, I don't think the Excels are the most detailed drivers I've heard, though they are very neutral and generally good. For example, the Fostex FE108E sigma is more detailed than the W12 IMHO, but more colored as well. Pick your poison...

Anyway, any number of different approaches can work. It's more important to design well, whatever road you decide to take.

Greg B

Sometimes, we're hearing "more details" that are little resonance of the drivers and coloration may enhance some sounds. As you wrote, we must choose our poison !
I think I will take the low sensitivity road with Orion's design.