In tweeter XOs you don't need big resistors. In fact, you don't need big resistors in most XOs. You'll also need to know the Z in the working range. Nominal Z isn't the answer.
In tweeter XOs you don't need big resistors. In fact, you don't need big resistors in most XOs. You'll also need to know the Z in the working range. Nominal Z isn't the answer.
so, you think in my application the 12w resistor will be fine? I'm an 8/10 listener. I suppose I could crack open my passives, and see what they are rated for
It's not only unnecessary to use big resistors, it's highly impractical. I have a couple non-inductive resistors, 4 ohms rated for 100 watts. They're 1.25 in diameter and 5 inches long.
You have to remember that your system is never throwing 300 watts at the tweeter. Music power and continuous power are quite different things. Not to mention, since the tweeter is 8 ohms, you're already seriously cutting into the amp's rated power. Add the series resistors and it's cutting further.
If there's an L-Pad in the factory XO, you'll have to know exactly what it's doing, as well as the driver Z it's working on. Once you know that, THEN you calculate the L-Pad values you're adding on. Most times a simple padding series resistor is all you need, in front of the XO.
i had planned on putting the lpad between the crossover and tweeter.
As you can see from your Z graph, Z-nom is not 8 Ohms. In the region of the XO, it'll be in the 5-6 ohm range. That changes things for the L-Pad somewhat. If you don't have the correct Z values, you'll also be changing the XO point or slope. This can be tricky stuff, and a lot depends on what's going on in the xo itself. Try a simple series 4-6 ohm resistor in series on the tweeter first to see what happens, and adjust accordingly.
The stuff you're messing with lately is to the point now where it's time to invest in some testing equipment so you have accurate information. There's no need to spend a bunch of $, but you will have to learn about how PC-based acquisition systems work. The best thing to do is download some sort of Program like Praxis, or Speaker Workshop and build test probes. You'll be much happier with reliable information
If you're referring to TrueRTA, it's very different (and limited) compared to a full test suite. Don't dump the $100 into upgrading from the demo. It can't do any Z or Phase measurements. The most important thing it can't do is gated measurements. It has it's functions, but it operates very differently than Praxis, CLIO or MLSSA.
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Is anyone familiar with LPAD construction?
