This is car stuff, but I need a more nuanced approach than is typical of car people for my plans.
I have a 4-5 step upgrade path that at first requires me to use passive crossovers for a pair of 6-3/4 front doors (tweeter goes in trash), and dash mounted 3-1/2 2-ways. Wiring is integrated and splits somewhere in the dash, there is also a 100uF cap inline with the dash speakers. (Phase 4 rewires these but lets not get ahead of ourselves). This cap should crossover the dash speakers at around 400 hz, which is fine. I purposefully didn't get a "nice" component set since I wasn't going to be able to use the crossovers (because no tweeter)
My question here is about adding an inductor to the doors. I have a few from past projects in the .3-.7mH range. Is it worth strapping one of these on(crossing over around 900hz) or should I spend $20 and get some solid core 3.5-4mH inductors instead to crossover around 150hz.
Thanks!
I have a 4-5 step upgrade path that at first requires me to use passive crossovers for a pair of 6-3/4 front doors (tweeter goes in trash), and dash mounted 3-1/2 2-ways. Wiring is integrated and splits somewhere in the dash, there is also a 100uF cap inline with the dash speakers. (Phase 4 rewires these but lets not get ahead of ourselves). This cap should crossover the dash speakers at around 400 hz, which is fine. I purposefully didn't get a "nice" component set since I wasn't going to be able to use the crossovers (because no tweeter)
My question here is about adding an inductor to the doors. I have a few from past projects in the .3-.7mH range. Is it worth strapping one of these on(crossing over around 900hz) or should I spend $20 and get some solid core 3.5-4mH inductors instead to crossover around 150hz.
Thanks!
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Yes, sorry i should have been more clear about what I was hoping to accomplish. This should sum them at +1db around 260hz (400hz on high pass, and 160hz on lowpass). The mid/tweeters have a response of 130-20K.
Are you talking about crossing the 6 1/2 door to the 1" door tweeter, or are you talking about something that also involves the dash? (By mid/tweeter, do you mean the smaller mid and tweeter co-ax?)
Got it, thanks 😉
I'd have to think the small inductor is going to decrease output over the breakup region, which is worthwhile.
If you're going to cross to the dash it would be better low, so not a bad choice there. 400Hz means you'll hear the total sound as coming from the dash, and the door will take a fair share of the output power.
The problem with the small inductor is going to be having them both play over a wide band between 400 and whatever the 6 1/5 goes up to. That could mean more comb filtering and power imbalance.. but say you increase the cross fairly with both drivers to 900Hz as you say, wavelengths will be smaller than 400Hz and crossing could get harder. Think that you won't have to move your head far without throwing the direct sound out of phase. The modes could also be more obvious due to the higher frequency.
If you go much lower, think about the natural rolloff of the dash speaker and the resonance impedance peak of the door. Both are going to affect what you do, maybe taking what should be a simple cross away from the wanted slope. One may become steep and the other may have a peak in the stopband. It's not that it can't be done though, it depends on the methods you want to use.
I'd have to think the small inductor is going to decrease output over the breakup region, which is worthwhile.
If you're going to cross to the dash it would be better low, so not a bad choice there. 400Hz means you'll hear the total sound as coming from the dash, and the door will take a fair share of the output power.
The problem with the small inductor is going to be having them both play over a wide band between 400 and whatever the 6 1/5 goes up to. That could mean more comb filtering and power imbalance.. but say you increase the cross fairly with both drivers to 900Hz as you say, wavelengths will be smaller than 400Hz and crossing could get harder. Think that you won't have to move your head far without throwing the direct sound out of phase. The modes could also be more obvious due to the higher frequency.
If you go much lower, think about the natural rolloff of the dash speaker and the resonance impedance peak of the door. Both are going to affect what you do, maybe taking what should be a simple cross away from the wanted slope. One may become steep and the other may have a peak in the stopband. It's not that it can't be done though, it depends on the methods you want to use.