I saw these copper plates out at Parts Express and thought they might work well for crossovers... I used a Dremel cutoff wheel to score the copper. Seems to work so far but I just finished them tonight.
Those look awesome. I personally haven't used them. I am curious the affects it might have on the inductors though. I would think that copper board might have an effect on them. You have dats now, you could test it.
That’s a good point. How would you test it? Just hook the leads up to each inductor in circuit?
Yes sir. Just make sure no amplifier is hooked up. Then test the inductance.
Well, 3 crossovers inductors all checked out fine. However, the fourth one, each inductor seemed to be about half. I’m assuming it is because of the way they are hooked up though, not because of the copper panel; since the other three, even the other one with more than one inductor, all checked out fine. This is the one that is measuring off:
That is weird. Did you make sure you were making solid contact with the part that was scratched off?
It's possible they were sent wrong. I would encourage testing it with dats before you wire it. I would say though, you should check your inductor layout to make sure you don't get crosstalk when it is complete. Here is a good resource for that.
Only thing I can see is that the 2 solder joints where the coils land on the same copper pad look like they should be re-flowed to eliminate their effects.
Did you clean / ScotchBrite the boards before soldering? This removes any impurities (oils, oxidation, etc.) to ensure the best possible solder joint. Just trying to eliminate that from the equation.
You should be able to measure each component by themselves, as long as you have a meter that can read capacitance and low resistance ( 1 ohm \ under ), using the data supplied. If they check out, then check you have everything laid out correctly and that there are no shorts between the copper pads. After that...
Are you connecting them to the wrong impedance driver? That'll throw off the crossover points and any other compensation designed into the network.
Just my thoughts on what "may" have an affect. If none of those apply, well...???
I will most likely be rotating (resoldering) the lower left inductor since its orientation may be an issue. When I desolder it, I’ll measure it out of circuit and see what I get. Then I’ll rotate it and try again. All the copper plates were cleaned prior to solder so I don’t think that is the issue. I’m using DATS V3 to measure everything and all the other boards were measuring fine so I think I’m good there. Lastly, I haven’t put them on any drivers yet while attached to the boards so driver impedance is not an issue yet. I hooked them all up with alligator clips etc...and it seemed to work great.
Ok, updated report. I hooked these all up and despite measuring weird, they work as expected! However, one of the “fun” things about diy speakers is I’ve decided to completely change the enclosure design. I’m not happy with the “peaky” response of the ported design so I’m going sealed. This allows me to make the enclosure smaller as well. Back to the drawing board!
Funny that you say that. I am in the process of changing an enclosure I just built. It works, but I really want to reduce some unexpected port noise. You never can tell what you will run into, until you run into it. I'm looking forward tot he new redesign.
Yeah, I’m just not happy with this sub in a ported setup. I think sealed is going to perform a lot smoother and while I’ll “lose” 3dB at 40hz, just about everywhere else it’s the same or better. Plus, I’ll be going from 1.25 cu ft down to about 0.75 cu ft so that’ll be a more appropriate size box I think too.
