$1 aurasound drivers in an array?

[rhubarb9999]

Re: $1 aurasound drivers in an array? They're here!!!

I think I'll go somewhere around 65 inches, give or take. Once I start routing the wholes, I might decide shorter is better;).
[ATTACH=CONFIG]32156[/ATTACH] [ATTACH=CONFIG]32157[/ATTACH]

I am working on a project with these. Use a Milwaukee 3" hole saw if you want to rear mount them. Its a perfect fit.

[mikejennens]

Re: $1 aurasound drivers in an array? They're here!!!

well, I'd start modeling and see. Throw a dozen drivers in Tolvan and see what happens.
Did anyone ever measured response of that tweeter? What's the distortion look like on the low end?

Well, I tried to figure out Tolvan (Edge) and I'm drawing a blank. I tried a few other speaker design software apps and I just don't get it. I've been able to arrive at a sealed enclosure for a single driver of about .9 liters in Unibox and Woofer Box and Circuit Designer, but that's all I've been able to do so far. I have a hard time wrapping my mind around the design side of things !

[Oscillate]

Re: $1 aurasound drivers in an array? They're here!!!

Basic question about designing a crossover for line arrays...

Let's say that each driver has a nominal impedance of 8 ohms, but that
after figuring out the series & parallel wiring of the line you arrive at 6 ohms
total impedance for the line. Normally you would use the impedance of the
driver at the crossover point when designing the crossover ...but with this
new ohm value, what do you do? ...Do you have to use WooferTester/DATS
and measure with the line wired together or is there another method that can
be used? Thanks

[billfitzmaurice]

Re: $1 aurasound drivers in an array? They're here!!!

Normally you would use the impedance of the
driver at the crossover point when designing the crossover ...but with this
new ohm value, what do you do? ...Do you have to use WooferTester/DATS
and measure with the line wired together or is there another method that can
be used? Thanks

Ideally measure it, but otherwise use the same correction factor between nominal and actual impedance as you have with a single driver applied to the nominal impedance of the array.

[jhollander]

Re: $1 aurasound drivers in an array? They're here!!!

Well, I tried to figure out Tolvan (Edge) and I'm drawing a blank. I tried a few other speaker design software apps and I just don't get it.

Mike, it’s been a while since I’ve messed with edge but it should be indicating the on baffle response of multiple drivers (theoretically). This should give you an indication of where the x-o point should be and what tweeter (s) will work. Snap some screen shots and share.

[mikejennens]

Re: $1 aurasound drivers in an array? They're here!!!

Mike, it’s been a while since I’ve messed with edge but it should be indicating the on baffle response of multiple drivers (theoretically). This should give you an indication of where the x-o point should be and what tweeter (s) will work. Snap some screen shots and share.

I was on Speak-chat with r-carpenter last night and he directed me to the instructions for "Basta!" I was at least able to see how placing different numbers of drivers on different sized baffles would affect the baffle step. Next time I pull it up, I'll post what I find.
Thanks John.

[mikejennens]

Re: $1 aurasound drivers in an array? They're here!!!

I'm back at these arrays again. I laid out 10 drivers in the Edge. my first screen shot is attached. First question I have is how do I make the baffle longer? I manipulated the numbers in the "Baffle Size" box, but it still stayed at/showed a 1 meter long baffle.
Next question is what am I aiming for with the trace in the response diagram? I would assume a flat trace, but I don't know that for sure. If I move the drivers off center, the trace becomes flatter.
So, am I safe in thinking the response diagram is telling me how much BSC I need for any given point/frequency on the graph? If so, do I want to bring it down to the blue line or just work to make the red line "as straight as possible" via baffle step correction?
Thanks in advance for the help.
Mike

[r-carpenter]

Re: $1 aurasound drivers in an array? They're here!!!

after inputting your X and Y and Applying, you can bring the pointer to the Y scale, move the baffle up or down or change "resolution" (again, by moving the pointer while on the Y scale)
You are aiming to see how much of a high frequency loss number of drivers and baffle shape will bring about. See the deepy area between 2khz and 3khz? That's where the crossover demons will be lurking.

[mikejennens]

Re: $1 aurasound drivers in an array? They're here!!!

after inputting your X and Y and Applying, you can bring the pointer to the Y scale, move the baffle up or down or change "resolution" (again, by moving the pointer while on the Y scale)
You are aiming to see how much of a high frequency loss number of drivers and baffle shape will bring about. See the deepy area between 2khz and 3khz? That's where the crossover demons will be lurking.

Thanks Roman,
So should I make it as flat as possible in the range in which I plan to use the array of drivers, then cross to the tweeter (RS28) where it starts getting not so smooth? For instance, in the screen shot attached to this post, cross to the tweeter at 2K. Am I on the right track?
Thanks again,
Mike

[r-carpenter]

Re: $1 aurasound drivers in an array? They're here!!!

well, that is certainly an interesting combo. You are on the right track in terms of manipulating Edge but remember that it models on axis response. This combo will most likely cause havoc off axis, especially after you add the tweeter to the array. I would suggest trying a simple line first, lets say out of 6 drivers. See what the response is in the possible crossover region with the driver compliment increasing. As you get the line taller and number of drivers increases, the deep between 2k and 3k will become larger and more difficult to work in the crossover. I like the idea of 9 driver array. Increase baffle width too. Why not try 18" wide?

[mikejennens]

Re: $1 aurasound drivers in an array? They're here!!!

well, that is certainly an interesting combo. You are on the right track in terms of manipulating Edge but remember that it models on axis response. This combo will most likely cause havoc off axis, especially after you add the tweeter to the array. I would suggest trying a simple line first, lets say out of 6 drivers. See what the response is in the possible crossover region with the driver compliment increasing. As you get the line taller and number of drivers increases, the deep between 2k and 3k will become larger and more difficult to work in the crossover. I like the idea of 9 driver array. Increase baffle width too. Why not try 18" wide?

Sounds good. If I go with an RS28, is (edited) 3K a good area to shoot for to cross from the Auras to the RS28? If not, I'm open to more advice. As far as on axis, in an array what is on axis? If I use 9 drivers in a straight vertical line, is on axis the center point of that line?
Once again, thanks for your help.
Mike

[r-carpenter]

Re: $1 aurasound drivers in an array? They're here!!!

you are very welcome. I hope I am making things clear enough and not confusing.
RS28 is a very capable tweeter that can play in blow 2k area. The reason I suggested it in the first place is if the array will fall short due to HF loss, RS28 will be able to keep up with it. Of cause, slope needs to be looked at and measured as you go.
"On Axis" is this case is a bit of a tricky question. Let's look at it as "on axis" with the tweeter after it's mounted on the array. Edge places mic at 1m and assumes that it's centered to the vertical size of the baffle at 0. It's a red dot that says mic and you can also move it around
The array response vertically will change as you move actual mic up or down from tweeter level. So, with the use of single centered tweeter the biggest concern is summed up arrival signal at the listening spot. It should be interesting to see on the actual build.

[mikejennens]

Re: $1 aurasound drivers in an array? They're here!!!

Definitely making things clearer. And thanks for your patience and time.
OK, here's a run with 9 drivers. It looks to me like there is less than 2dB of baffle step in the region I'm thinking of using the Auras, considering the RS28 can cross lower than I mentioned earlier. Would it make sense to cross at 2.5K to the RS28? I'll fill the bottom end, below 300 Hz, with either a sub or work a bass section for it AFTER I get this part done. I figure the tweeter could go where I have the mic. If I need to put the array on some sort of riser, that's fine; that might be how I add some bass to it later.


...

[jhollander]

Re: $1 aurasound drivers in an array? They're here!!!

Mike where is your mic position? I don’t see it in your screen shots.
You may want to reduce you listening distance to less than 100 meters.

Also do the same baffle with your tweeter(s) in a separate edge session

[mikejennens]

Re: $1 aurasound drivers in an array? They're here!!!

Mike where is your mic position? I don’t see it in your screen shots.
You may want to reduce you listening distance to less than 100 meters.

Also do the same baffle with your tweeter(s) in a separate edge session

Hi John,
On the last post, the mic is about .65 meters up. I wasn't sure about the 100 meters, but that was how it opened, so I didn't notice it until I had run it a few times. When I moved the mic to one meter, it showed about 16 dB or more of baffle step. is that what I should be working with? Thanks for the tip about doing the mic on its on edge session.
I'd love to stay up and keep working on this, but I've got a long day at work tomorrow, so i need to call it a night. I will be back, though.
Thanks,
Mike