Van Zyl BB10 Horn Subwoofer

[morricab]

101dB each

They are in parallel or series?

 

[christensenleif@msn.com]

They are in parallel or series?

parallel

 

[Kingrex]

If you want a horn bass below 20 Hz, it looks like this. Or with a tapped horn.View attachment 154890

But it's rather unrealistic in normal living spaces, so stick with 30hz, it's easier to achieve. no need 20hz, that will cause more problems than benbenefits

Wow. Massive. This is Johan's 12 inch horn. I think he said it only goes 3 hertz lower than the BB10, but the output of power is much higher. He personally likes the BB10. So do I.

 

[Robh3606]

The larger, likely higher sensitivity woofers are moving much less to compress the air with the same amplitude. This means they have much higher acceleration to produce the same amplitude wave as the smaller long stroke woofers.
Probably the smaller ones require 10x or more power to achieve the same SPL as well, meaning higher mass and/or weaker magnets.

How's that? It's acceleration is a slave to the input signal. It can't go faster and complete 10 cycles of a 30Hz sine wave before the 10" driver. The period of the sine wave set's a speed limit. The change is in excursion and we all know that smaller drivers have to work a lot harder for the same SPL. The smaller driver has to complete a cycle in the same time period with greater excursion. Greater distance over the same time.

Who's accelerating faster? Seems it's the other way around the 15 with larger surface area has to work a lot less and requires much less power to do so.

Rob

 

[morricab]

How's that? It's acceleration is a slave to the input signal. It can't go faster and complete 10 cycles of a 30Hz sine wave before the 10" driver. The period of the sine wave set's a speed limit. The change is in excursion and we all know that smaller drivers have to work a lot harder for the same SPL. The smaller driver has to complete a cycle in the same time period with greater excursion. Greater distance over the same time.

Who's accelerating faster? Seems it's the other way around the 15 with larger surface area has to work a lot less and requires much less power to do so.

Rob

You’re not thinking about it correctly. The acceleration, area and mass of the cone determine how much force the driver applies to the air, which compresses. More force = more compression = higher SPL. A 10 inch driver travelling a longer distance might move the same volume of air as a 15 inch driver moving less but it will compress the air less resulting in a lower SPL. Two drivers the same diameter but one 88dB and the other 95dB will have different capability for air compression with a 1 watt drive signal. That capability will be related to magnet strength and cone mass…a lighter cone with high magnetic strength gives high acceleration that more efficiently compresses the air.

For example, I have 8 inch drivers from Supravox that are 99dB sensitivity. They have only 7 grams moving mass and a large 1.9 T ALNICO magnet. Large magnet, low mass high sensitivity. The downside of this is a very low Qts, which means they are best suited for horns. When they are loaded into TQWT cabinets I get 30Hz in room with them. Load them in a large reflex you won’t get close to that.
Of course higher mass lowers the resonance frequency and smaller magnet raises Qts (there is another version of my drivers with 1.4T magnet and 8.5g cone that has mor reflex friendly parameters), allowing them to be reflex or sealed box friendly but with lower acceleration and therefore lower SPL for a given input signal.

 

[JohnP]

Great session with the designer Johan. Deep knowledge on horn design. He talked a whole lot about philosophy and design. Why horn subs are superior to a cone in a box.

On a simple level, as I understand, a horn woofer excells as it has high impulse power and speed. The BB10 is 106 db efficient. The driver excursion is very small to get the same volume of sound compared to a low efficiency driver in a box. He explained it like this. You have a 10lb weight in one hand. Your arms are wide apart. How much effort and how quickly can you move that weight from on extended arm over to the other arm and back again. Now do that again but hold your hands 5 inches apart. Its much easier and much quicker. Same with a horn assisited driver. The cone hardly has to move and the ability to stop it and reverse its direction is small. That is why so many subs fail. Why you hear people say they can't get them to work. They are slow, and bloated. To try and make them work, they build large line arrays of stacked subs and use thousands of watts of power. They are trying to use surface area and power to reduce the amount of excursion needed to move air. But you still have bass that is heavy with overhang. It may go to 20 hertz. But is it a good 20 hertz bass.

With a horn, Its fast, tight, natural and keeps up with the main speakers. As such, its been easy for me to sit with the amp in my lap and dial it in by ear. Its easy to have all the bass I need with a single 10 inch driver.

FWIW, Johan was telling me he makes some 12" and 15" versions of horn subs. He has to use aluminum drivers. For some reason the force on the cone shreds the drivers made of paper. They fall apart after 3 days. Thats 3 days. There is a lot of power in that horn.

With the BB10, he impregnates the paper front and back with something. I think it’s on his website. Its dramatically stiffens the driver cone and keeps if from falling apart. This sub is not joke. It puts out serious power.

I’ve known Johan for years. His horn-loaded subs produce the cleanest and most impactful bass I’ve heard. Glad to hear that he’s getting the recognition he deserves.

John P.

 

[Kingrex]

I'm a believer. I held off on subs for years. So many people say they don't work. Or you don't ever hear them at all. Maybe there is a touch of clarity gained.

I did purchase a Velodyne but got rid of it right away. Then a friend brough REL to my house. Used them (2) for a week and sent them back. I watched a friend build subs. He was always looking for the drivers with the greatest excursion and using a Krell to power them. He also had SVS. He thought he had good bass. He bragged he was an expert on bass. I even felt he had good bass. Yet there was something about his system that made me say, even if you gave it to me, I wouldn't use it. I thought is was the SS amps. Maybe it was the subs. Maybe a combination of both. Sorry, I'm a die hard tube guy. I have heard good SS. And I even came close to getting the Soulnote A2. After my BB10 sub arrived, I knew I had the right gear. That sub does everything I was hoping it would do.

Johan's prices are very reasonable. Same as say a premium JBL. And you only need 1, not 2 to 4. And he personally gets on the phone and coachs you through setting it up. He wants to come to my house and dial it in. Included in what I paid. I am not ready for that. I have to finish the room first. I can't see why anyone wouldn't try one.

I am even leaning toward getting his complete horn system. He has something new in the pipe. I want to see what it is. And, its designed around using my amplifier.

 

[morricab]

I'm a believer. I held off on subs for years. So many people say they don't work. Or you don't ever hear them at all. Maybe there is a touch of clarity gained.

I did purchase a Velodyne but got rid of it right away. Then a friend brough REL to my house. Used them (2) for a week and sent them back. I watched a friend build subs. He was always looking for the drivers with the greatest excursion and using a Krell to power them. He also had SVS. He thought he had good bass. He bragged he was an expert on bass. I even felt he had good bass. Yet there was something about his system that made me say, even if you gave it to me, I wouldn't use it. I thought is was the SS amps. Maybe it was the subs. Maybe a combination of both. Sorry, I'm a die hard tube guy. I have heard good SS. And I even came close to getting the Soulnote A2. After my BB10 sub arrived, I knew I had the right gear. That sub does everything I was hoping it would do.

Johan's prices are very reasonable. Same as say a premium JBL. And you only need 1, not 2 to 4. And he personally gets on the phone and coachs you through setting it up. He wants to come to my house and dial it in. Included in what I paid. I am not ready for that. I have to finish the room first. I can't see why anyone wouldn't try one.

I am even leaning toward getting his complete horn system. He has something new in the pipe. I want to see what it is. And, its designed around using my amplifier.

IMO, nothing beats the quality of horn bass. The horn is doing much more work on the output than other bass loading schemes.