Alpair 12p and HiVi RT1C-A crossover design

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hi
I want to cross the alpair 12p The Madisound Speaker Store between 6 or 8 KHZ to the hivi RT1C tweeter HiVi RT1C-A Planar Isodynamic Tweeter | 297-400

I want to cross at 8 khz to avoid the problems after 6khz- 8khz that my measurments shows me. I want a passive first order XO, nothing else.

Can anyone help me design the crossover, I have really no idea how to do it.

thanks
 
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I will need the following:

1- your on-axis measurements for both drivers

2 - in box impedance measurements for both drivers if you can (if not, I can use the manufacturers' impedance graphs

3 - relative driver locations on the baffle

That should get me some fairly accurate simulations.
 
Yes, if you consider them accurate, actual in box measurements are the best ones to use.

If not, I'll use the manufacturer's measurements and then add in the appropriate baffle diffraction and baffle step loss. In this case, I'll also need to know the baffle dimensions of the box, port tuning and what the box will be sitting on - a stand or something else.
 
this is my measurments for the alpair.look at the yellow line
I thought that it could be a good idea to cross at 4 khz to avoid some of the peak from 4khz, but I think I dont hear it too bad, but as you can see, from 8khz, the alpair consideraly rolls off. so a 8khz xo is absolutely needed... or maybe 4 khz? you guys are the judge!

People seem to say that the RT1 cannot really go under 5khz, and since I want first order, I guess the lower limit is 5khz first order...
 

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Crank up the gain on the impulse plot so you can actually see it, left-click around where I put the yellow circle, right-click around where I put the red circle, click the 2FR button at the top, make the response graph much larger with 1/12 octave smoothing, and let's see that. edit: oops, forgot the image, there ya go:
 

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BTW, the other day, ive filled the ports of my box with socks, and the peak at 100hz was greatly removed.
what I would like to do, is redo the front baffle on my actual BR, have a sealed enclosure with the alpair on the bottom and the tweeter on top. I use a subwoofer so dont need the BR advantage anymore.

I forget the hivi tweeter, it wont go enough for my needs.

My goal is a XO around 3 khz to avoid that 3khz peak...

that looks to be a good tweeter http://www.madisoundspeakerstore.co...discovery-r2604/8320-1-tweeter-ring-radiator/
and this tweeter too: http://www.madisoundspeakerstore.co...b-acoustics-sb29rdc-c000-4-ring-dome-tweeter/

which one should I use?
 
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I was only asking because you don't have a calibration file loaded in ARTA, not a big deal. Your measurement looks approx. right above 1k, but I think you should re-do it as I described. Maybe a gentle shelf that pulls the average level down would be a good plan before figuring out what else to do, but it's hard to tell what's happening from the graph you posted.
 
I use two different mics and both shows me the same FR

BTW, I might want to expand my tweeter choice. anything under 70$ is a good option for me, to maybe xo the alpair lower, like around 3khz to avoid most break ups problem?

your placement for the tweeters and ur reference axis will determined the xover.

you may need to consider how loud you want to listen to determine what kind of speakers you want to have.

i would suggest to keep an open mind towards your approach for the 2way.

the goals should be :
1. smoothesst response
2. even dispersion
3. good phase tracking so u get a good soundstage

cheers
henry
 
I'd suggest the LD22 tweeters from CSS Sound. They are Canadian and it is a silk dome with lots of measurements. I haven't heard them but the LD25x was pretty good. The LD22 is in your price range and shipping is reasonable since you don't have to worry about the border.
 
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