Does the coupled value change with voltage or is it a constant?
I will need to stack a couple of inductors for the bottom end of my three way as well.
Don’t know. I’m using a DATS V2 to make the measurement, so I’m stuck with the fixed, small test voltage that DATS V2 is using. Can DATS LA vary the test voltage?
Also, I was thinking about setting up a breadboard type testing station on my bench using a function generator/power amp/o-scope/inductor/dummy load/distortion analyzer, etc., and then testing this for myself. I would test for both distortion and loss of in/out voltage at various low frequencies and power levels. But I am running out of time and need to button these speakers up for Indy. Maybe after Indy.
Can you use your two-channel measurement rig (Magic Box of Wonders version) and REW to measure inductance?
Yes, I could set up a simple loopback test and measure with either ARTA, REW or SE. EDIT:
And I should be able to vary the testing power level so that I can see how much the inductor’s distortion or value changes. Right now, I’m in the process of setting up a laptop/REW workstation on my test bench to test amplfiers and preamps. It will be a simply matter to test a single inductor (or multiples in a stacked series). But that is not set up quite yet. In the meantime, I’m lazy, so I usually just grab my DATS V2 to measure inductors.
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I talked to several people at InDIYana about why my speakers sounded somewhat bright and harsh compared to most of the other speakers at the event. Several ideas were put forward, but I think the basic problem is that the RD40’s are a line array and, as such, they generate a cylindrical wavefront. Most of the other drivers at the event were conventional point source types, which generate a spherical wavefront. Due to coupling, the SPL level of a cylindrical wavefront drops off at a much slower rate compared to a spherical wavefront. Since my VituixCAD model was set up based on the way drivers with spherical wavefronts propagate into a room, they ended up sounding bright and harsh. The solution is to re-design my crossover to account for this difference in roll off rate. The on-design axis frequencies covered by the RD40’s need to be targeted to slope down by about 6dB or so, instead of being targeted to be flat on-design axis. Live and learn. Line arrays are a completely different animal.
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Even though they were a bit bright at the event, I think you are going to complete this project with them and do them justice. You don’t have far to go.
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I only got to hear them once, but thought they presented well. I tend to like a bit of zing to a speaker and thought yours sounded fine, IMO of course. Maybe the ol BBC dip would be a good idea in it’s regard?
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