Crossover Distortion?

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OK to make a long story short, I built a passive crossover for a pair of MB Quart 6.5's in my car. I used the Crossover Calculator found -HERE- and decided to go with a Second Order (12db/octave).

The Crossover was calculated with a 3200 Hz freq range and 4 ohm speakers.

I built ONLY what is shown in the calculator diagram and hooked them up. I have my amp running at Full range and when the bass hits there is a lot of distortion. You can tell that the higher frequencies have been cut out, but even at a very minimal volume level, for lack of better words they "sound like crap".

I purchased the Inductors and Caps of Parts Express.

If it helps, I have tested the speakers on another amp without the crossovers and they are not blown. Also when I put the amp on High pass I get non distorted music from the speakers but it doesn't sound like the correct freq range.

Anyone know what could be wrong with these things?

An externally hosted image should be here but it was not working when we last tested it.
 
OK well, I made some Diagrams of the Crossover layout and simple schematics. I also have attached a picture of the wiring on the back of the crossover. It probably will not help since it's Point-to-Point wiring and the picture is hard to see.

Crossover Diagram:

An externally hosted image should be here but it was not working when we last tested it.


Simple Schematic:

An externally hosted image should be here but it was not working when we last tested it.


Pictures of Wiring:

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.


Hope this helps.

Brian
 
Killjoy99


The problem you might have with the arrangement of the inductors is magnetic field coupling from one inductor to another. With the inductor, laying down and in the same magnetic plane the low frequency can cross couple to the midrange inductors. You should take the inductors for the midrange drivers and stand them on edge at a right angle or increase the distance between them. ;)
 
The schematics and component values seem reasonable. The potential mutual coupling between the coils can be handled by changing the direction of the two middle coils such that only the two coils at the far ends point in the same direction. There is also a slight risk that the iron in the screws increases the value of the coils a bit. But as I said both of these effects are small, and probably *not* the cause to your problem.
You have not yet said anything about the speakers, more than that they are 4 ohms. There is a risk if the woofer has a high voice coil inductance that there will be a dip in the impedance curve near the xover frequency. On the other hand, the symptoms you describe do not match this entirely. Also, you should not run this filter *without* the drivers connected, since this will lead to a very sharp impedance dip at the xover freq.
Could you post the brand & model of the speakers too?
 
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