Is it possible to cover the whole spectrum, high SPL, low distortion with a 2-way?

2384 is ok but due to its small size it looses the directivity quite early. I have the polars but I don't think I'm allowed to share them. A larger well built horn is in another league, but also takes up more space and will cost more.
Combining it with a 15" in a vented box (preferably 140 L or bigger) works really well and blows away any "high-end" commercially speaker out there IMO.
 

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Hi Omholt,

Great looking new horn! How far down in frequency does the horn load, and what driver are you using?

Thanks!

Best regards
Peter

2384 is ok but due to its small size it looses the directivity quite early. I have the polars but I don't think I'm allowed to share them. A larger well built horn is in another league, but also takes up more space and will cost more.
Combining it with a 15" in a vented box (preferably 140 L or bigger) works really well and blows away any "high-end" commercially speaker out there IMO.
 
Hi Omholt,

Great looking new horn! How far down in frequency does the horn load, and what driver are you using?

Thanks!

Best regards
Peter
The horn to the left is Klipsck K402 which I assume you're familiar with. The horn on the right side is a prototype I have and working on. It loads down to about 300 Hz. I'm testing with both Radian 951, JBL 2450SL and other drivers.
 
Thanks! How does the new horn compare to the Klipsch?

Best regards
Peter
Too early to draw any conclusions and I'm waiting for a new pair with better build quality. So far though, my impression is that it's a few steps above the K402 even when comparing with a low cost diaphragm to a beryllium in the K402. The horn is really more important than the driver/diaphragm.
 
Hi again Omholt,

Thanks for the reply! That sounds really interesting. Where do you cross over to the woofer, and what 15" are you using?

Best regards
Peter

Too early to draw any conclusions and I'm waiting for a new pair with better build quality. So far though, my impression is that it's a few steps above the K402 even when comparing with a low cost diaphragm to a beryllium in the K402. The horn is really more important than the driver/diaphragm.
 
Hi again Omholt,

Thanks for the reply! That sounds really interesting. Where do you cross over to the woofer, and what 15" are you using?

Best regards
Peter
Around 600 Hz with this horn. I can cross over lower with another horn that I'll also will test. But 500-600 Hz area seems to be basically the lowest you can go with most beryllium 4" compression drivers. Perhaps somewhat lower with a very steep filter.

It's not important what 15" driver I'm using. I trying a lot of things. The final setup will by the way be with a midbass horn as the picture below shows (a 3-way system). I'm simply using a vented woofer as well for test purposes. But if you want a recommendation for a quality 15" woofer with high sensitivity I would recommend a driver from Acoustic Elegance.
 

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Thanks! Looks great:).

Best regards
Peter

Around 600 Hz with this horn. I can cross over lower with another horn that I'll also will test. But 500-600 Hz area seems to be basically the lowest you can go with most beryllium 4" compression drivers. Perhaps somewhat lower with a very steep filter.

It's not important what 15" driver I'm using. I trying a lot of things. The final setup will by the way be with a midbass horn as the picture below shows (a 3-way system). I'm simply using a vented woofer as well for test purposes. But if you want a recommendation for a quality 15" woofer with high sensitivity I would recommend a driver from Acoustic Elegance.
 
Around 600 Hz with this horn. I can cross over lower with another horn that I'll also will test. But 500-600 Hz area seems to be basically the lowest you can go with most beryllium 4" compression drivers. Perhaps somewhat lower with a very steep filter.

Agreed on the crossover freq.

But why the hard vertical diffraction slot in your new horn?
That will generate lots of HOMs. Wouldn't a smooth round-to-rectangular transition be far better?

Marco
 
Agreed on the crossover freq.

But why the hard vertical diffraction slot in your new horn?
That will generate lots of HOMs. Wouldn't a smooth round-to-rectangular transition be far better?

Marco
HOMs seems to be an idea of something, not something we know scientifically about. But either way, your question is whether a diffraction slot is a problem causing audible anomalies.

IMO this doesn't seem to be an issue at all with a large horn, a good driver and EQ. This horn sounds smoother than Klipsch K-402 which has a round transition.

Keep in mind that the older JBL diffraction slot horns were much smaller with higher crossover, had poor drivers compared to what we have today, and used passive network with no possibilities of EQ. Things have changed and the benefit of a diffraction slot is an extreme constant directivity combined with remaining the directivity high in frequency.

Actually equalizing will work quite well (if you actually worry about the small response aberrations) because the gap reflection effect is definitely minimum phase. It is guaranteed minimum phase up to the point where the reflected wave is of the same magnitude as the input magnitude, which is definitely not true. Constant coverage/beamwidth wins out every time IMO!
 
Agreed on the crossover freq.

But why the hard vertical diffraction slot in your new horn?
That will generate lots of HOMs. Wouldn't a smooth round-to-rectangular transition be far better?

Marco
One more thing. I have had a pair of Abbey speakers (Geddes design) FIY. They didn't sound smooth at all to my ears. However, I think part of the problem was the breakup from the driver above a certain frequency. Besides sound harsh when they had sufficient level for a correct response, they also sounded quite muffled with lack of "sparkle" in the highs.

Quite honestly, I think this HOM theory is a bit dubious, but I could be wrong. For me the combination of a large horn with low crossover, constant beamwidth combined with a quality driver and EQ is what I really believe in and have found to sound best by far.
 
For me the combination of a large horn with low crossover, constant beamwidth combined with a quality driver and EQ is what I really believe in and have found to sound best by far.

Interesting viewpoint.

FWIW, I fundamentally agree on the use of a large horn & low crossover + quality driver...

In my own system, I use a JBL driver with a 4" Be diaphragm and a Yuichi Arai horn (which is almost constant directivity in the horizontal plane over the critical 600-6k bandwith - albeit definitely not constant directivity in the vertical plane), plus a high-quality supertweeter for the top harmonics (which, to my ears - and critically, when driven by a suitable amplifier - sounds more "real" than any largish compression driver could ever hope to).

Marco
 
Interesting viewpoint.

FWIW, I fundamentally agree on the use of a large horn & low crossover + quality driver...

In my own system, I use a JBL driver with a 4" Be diaphragm and a Yuichi Arai horn (which is almost constant directivity in the horizontal plane over the critical 600-6k bandwith - albeit definitely not constant directivity in the vertical plane), plus a high-quality supertweeter for the top harmonics (which, to my ears - and critically, when driven by a suitable amplifier - sounds more "real" than any largish compression driver could ever hope to).

Marco
I can understand why you prefer a supertweeter when you horn looses its directivity so early (6kHz horizontally). When the horn remains the directivity till 12-15KHz (15KHz with the horn I'm testing now), I'm not so sure of the benefit anymore. Plus you add phase issues leading to combing and lobing. The distortion is already very low with a 4" Be driver in the highs, but you do of course get higher sensitivity with a smaller driver.
 
One more thing. I have had a pair of Abbey speakers (Geddes design) FIY. They didn't sound smooth at all to my ears. However, I think part of the problem was the breakup from the driver above a certain frequency. Besides sound harsh when they had sufficient level for a correct response, they also sounded quite muffled with lack of "sparkle" in the highs.

Quite honestly, I think this HOM theory is a bit dubious, but I could be wrong. For me the combination of a large horn with low crossover, constant beamwidth combined with a quality driver and EQ is what I really believe in and have found to sound best by far.

just wanted to comment about horns with diffraction slots. In my limited experience they don't seem to exhibit any issues (or they exhibit diminished levels of issues) when played at normal home levels and only seem to spit and sputter (like frying eggs) at very high playback levels.
So I would expect the problem is one of high level playback generating very high air velocity and or high air pressure. Compression drivers with low compression ratios seem to introduce fewer problems. Is it possible that diffraction slot horns become non linear at high playback due to vortexes or disturbances at the point in the horn where air flow becomes disrupted/non linear? Thanks for the interesting thread.
 
just wanted to comment about horns with diffraction slots. In my limited experience they don't seem to exhibit any issues (or they exhibit diminished levels of issues) when played at normal home levels and only seem to spit and sputter (like frying eggs) at very high playback levels.
So I would expect the problem is one of high level playback generating very high air velocity and or high air pressure. Compression drivers with low compression ratios seem to introduce fewer problems. Is it possible that diffraction slot horns become non linear at high playback due to vortexes or disturbances at the point in the horn where air flow becomes disrupted/non linear? Thanks for the interesting thread.
Higher sound level obviously makes issues more pronounced but think whether it's problem at all depends on the factor I mentioned earlier. When it's minimum phase behavior it can be dealt with by applying EQ, thus it's really gone.
 
@Omholt,

How does it compare to the CBT you have there?
I have two types of CBT speakers and starting working on the third type which will have better woofers and smaller full range drivers that pushes lobing higher in frequency. The third should be the best CBT so far.

I haven't done much of quick AB testing, which I personally prefer for more accurate descriptions of differences. So take this with a grain of salt. When it comes to what I prefer I like to listen to both over time.

Both are awesome. The horn sounds perhaps more immediate. Especially using a midbass horn makes it more effortless and if you crank up the volume the mid and upper bass can hit you in the chest and it's still super clean. The CBT is probably a bit more coherent but both are great in that regard. I think the horn gives the greatest illusion of real music but the CBT isn't far behind. The CBT is a better speaker for background music when you walk around in a wide room because of the wider dispersion. Obviously you need to treat the side walls for best imaging, but so do you with the horn also to some degree while it minimizes the side wall reflections more. The CBT completely avoids floor reflections which is really neat. No need for floor treatment. I could live happily with both. :)