Can they?

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Rog Mogale wrote: Hi Bitzo,

My sims for the 2 x 18TBX100 were 2 drivers with a single port 20 cm x 56 cm x 30 cm deep between both drivers. So a bit like a G sub. Cab was simed on the floor with horizontal positioning. The port was tuned to the resonance of the drivers, so 34Hz.

The mini scoop you simed looks to have an f3 of around 40Hz, so will have a higher sensitivity than all of my versions. They all aim for an f3 of 30Hz or just below, so will lose a few dB compared to a design that aims for 40Hz. The trouble is that we are both doing sims for different cabs, so our results will differ. If someone can post the input data for something like Stipes mini scoop, I can compare one of those vs a double 18 reflex with the same drivers. Of course both the mini scoop and the reflex would have to have the same f3, if not the design with the narrower bandwidth would be relatively louder.
.......
Rog.

Hi rog, thanks for your explanation . Now I modeled a gsub with your specification as a reference cab. Do you think that a mini-scooflex-wheatever f3 have to aim for the driver fs too?

however..I changed my sim this is a mini 2.83V VS b&csub218 2V both 18tbx100 loaded. B&C sub 218 stacked horizzontally, port coupled to the ground.
[attachment=0:23hpvei8]<!-- ia0 -->becsub218hvsmini18.jpg<!-- ia0 -->[/attachment:23hpvei8]

How do you sim port to the ground, and 218 stacked horizontally or vertically? Is it on akabak? have you an example? Thank.

in akabak you can take care of the position of the radiators. So for example a cab like gsub if you want a port sitting on the ground you have to put y={hp/2} where hp is the port's height, same concept for driver radiator. If you don't define that stuff and you have more than one radiator, like scoop, ported horn, etc... the radiators fire from the same point.

I've already tested to change Y, it makes a difference when you sim at 1 meter. But if you compare sims at 10 meters (increase voltage to 28.3volts) the change Y, it's like no difference You have to put high values like Y=2meters to see a small change. So I think Akabak only calc the distance of the port to the virtual mic measurement, then increase or decrease gain, but don't calc real gain of the port on the floor.

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Rog Mogale wrote: I’d personally like to hear Levyte's opinion about all this, as when I was in the UK the last couple of times enough ‘professional’ soundmen had bad things to say about him. I couldn’t believe it when I was told they thought he had just learnt a few formulas to further his career via the internet and that they laughed that he had the audacity to advice people after he had only done a couple of small wedding type events with a few scoops.

So come on Lev, put these peoples bad thoughts to rest and put the record straight. I have believed in what you said since the beginning and never thought you just used the internet to further your existence.

Rog.

Off the forums, I've been schooled by and have done business with many who know exactly what their doing, and have refined the art of getting huge, crystal sound, with not that much equipment. These are the kind of people I listen to... :lol:

Seems simple mods of Staiper MS18, will bring performance very close to Shorty mini.

Rog Mogale wrote: I’d personally like to hear Levyte's opinion about all this, as when I was in the UK the last couple of times enough ‘professional’ soundmen had bad things to say about him. I couldn’t believe it when I was told they thought he had just learnt a few formulas to further his career via the internet and that they laughed that he had the audacity to advice people after he had only done a couple of small wedding type events with a few scoops.



Rog.

I think there may be a couple of reasons Lev:
1: You can and have actually been bothered to research your science, and have the ability to understand it,
2. You openly discuss it, and as we all have learnt, everything should be kept a big secret smiley5

Jealousy is in there somewhere too.

Top bloke, keep the knowlege coming smiley20


These MS18 mods the same ones I did?

nickyburnell wrote: I think there may be a couple of reasons Lev:
1: You can and have actually been bothered to research your science, and have the ability to understand it,
2. You openly discuss it, and as we all have learnt, everything should be kept a big secret smiley5

Jealousy is in there somewhere too.

smiley32

smiley2