Crossover point Suggestions.

[frac12]

hi, I've been playing with different crossover points for the last year or so in my car, I'm just looking for your thoughts and maybe new things to try. so i have a Kia rio sedan.
subwoofer is a 15 inch Sundown audio in a sealed box in the trunk.
from that to my Dynaudio MW-172 8 inch in my lower front doors.
and from that to a pair of Morel INTEGRA424 I installed in the top of the same doors.

right now I've got 100hz at 12db between the sub and Dynaudios, and about 600hz 12db between that to the morels.

it sounds pretty good. but I'm curious of what you guys think of this? would you change anything?

thanks

[Notloudenuf]

What are you trying to improve? If you want more upfront bass lowering the sub midbass crossover might help that. You have 8s in the doors. At some point they could play low enough to start rattling the doors and that would screw up your image and sound quality. I would turn the sub off and lower the midbass crossover until it started rattling the doors and then turn it back up until it quit. Then bring the sub in below that. If 80 or 63 is the midbass point bring the sub in at 63 or 50. There will be enough overlap in crossover that you won’t miss anything.

YMMV all of this is my opinion

[frac12]

What are you trying to improve? If you want more upfront bass lowering the sub midbass crossover might help that. You have 8s in the doors. At some point they could play low enough to start rattling the doors and that would screw up your image and sound quality. I would turn the sub off and lower the midbass crossover until it started rattling the doors and then turn it back up until it quit. Then bring the sub in below that. If 80 or 63 is the midbass point bring the sub in at 63 or 50. There will be enough overlap in crossover that you won’t miss anything.

YMMV all of this is my opinion

hey, I never thought of doing it like that thanks.(turn the sub off and lower the midbass crossover until it started rattling ) I'm gonna give this a shot.

and how about the upper crossover point. 600hz~ would you leave it at that.. or do you think it's too high? I know the Morel's have an fs of 120hz but, I'm not sure how low i can go with these.?

[Notloudenuf]

Since I don’t know any better the 600hz high pass on the midbass seems ok. The midrange doesn’t need to play anything that would cause distortion so that 600hz range is probably the right low pass for it. Remember there is considerable overlap in frequency when using a 12db slope. So the midrange is playing lower it’s just 12db quieter each octave lower.

[frac12]

ok, makes sense, would i see any benefits if I go lower with a steeper slope, like 18 or 24db? or should i leave it at 600hz and 12db.?

[Notloudenuf]

I personally wouldn’t go lower but I would use a steeper slope. Personal preference is 24db.

[frac12]

Alright, sounds good.i'm about to install a helix dsp mini, so i'll be able to do that now, before it i was using the amps filters. thanks for your help.

[TheTodd]

I have my 8” midbasses & subs crossed at 70Hz @24dB and they perform very well with minimal buzzes or rattles, but that’s with heavily deadened door panels. I also have a 350Hz @24dB crossover point between my 8s and 3” mids. I’m not familiar with the Morels you have but, guessing by the model number, if they’re 4” you could get away with a much lower crossover point if your stage seems to pull down. You can use the same method for the mids as you do with the midbasses… mute everything else and lower the crossover until you hear distortion or any breakup. There’s no set of crossover points that are one size fits all… every install can effect the frequencies needed to produce optimal results.

One thing to remember about crossover slopes is that for every 6dB slope, it introduces 90 degrees of phase shift. Every install is different but if you’re using 12dB/oct slopes, theoretically your drivers are now 180* out of phase from each other. So using the popular 24dB slopes brings everything back around to 360* and everything is in phase again. Plus it’s a little more of a safeguard to keep unwanted frequencies out of your speakers.

[frac12]

I have my 8” midbasses & subs crossed at 70Hz @24dB and they perform very well with minimal buzzes or rattles, but that’s with heavily deadened door panels. I also have a 350Hz @24dB crossover point between my 8s and 3” mids. I’m not familiar with the Morels you have but, guessing by the model number, if they’re 4” you could get away with a much lower crossover point if your stage seems to pull down. You can use the same method for the mids as you do with the midbasses… mute everything else and lower the crossover until you hear distortion or any breakup. There’s no set of crossover points that are one size fits all… every install can effect the frequencies needed to produce optimal results.

One thing to remember about crossover slopes is that for every 6dB slope, it introduces 90 degrees of phase shift. Every install is different but if you’re using 12dB/oct slopes, theoretically your drivers are now 180* out of phase from each other. So using the popular 24dB slopes brings everything back around to 360* and everything is in phase again. Plus it’s a little more of a safeguard to keep unwanted frequencies out of your speakers.

Interesting, Ya these are 4" coax.and my doors and pretty well sound proofed. I will try to lower the crossover point of the mids, now i can't wait for my dsp to get here so i can try all these things you guys suggest. thanks

[TheTodd]

Helix c1? I hear only experts in the business and phd's can set that thing up correctly. It's got quite a pop. 1200 watts to 2000 watts to one amplifier with a mid-bass crossover in built to the setup. Wow. That's like for a mid-range or two-way speaker acting as a subwoofer. So you'll have the mid-ranges as a subwoofer but the in built crossovers are used. Only one amp but a subwoofer added to the system. You must be an expert at this already.

WUT?