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View Full Version : Midbass Speaker crossover points??



C3 Customs
03-11-2009, 09:49 AM
What crossover points do you use for your midbass & and for those that use passive crossovers which ones and why?

cbrei1023
03-11-2009, 09:50 AM
Midbass ive crossed as high as 400 and as low as 200. I currently run the Type-R passive crossover because it came with my Type-R components.

C3 Customs
03-11-2009, 09:54 AM
Midbass ive crossed as high as 400 and as low as 200. I currently run the Type-R passive crossover because it came with my Type-R components.

What DB gain do you have the crossover set to +3dB, 0dB, -3db or does it not have a choice? If am I using the wrong terminology, please someone correct me.

cbrei1023
03-11-2009, 10:15 AM
On the passives? There is no choice and I am not sure what it is. i only have tweeter level adjustments. My active crossover was a Memphis 16-X03 and I believe it was 18db slope on the HPF and 24db slope on LPF

etznova
03-11-2009, 11:02 AM
I'd be curious to know also. and only as low as 200 that just doesn't seem low enough

FoxPro5
03-11-2009, 11:08 AM
It's install and driver dependent. Due to speaker placement being limited, many opt for doors. Trying to cross a MB at 50hz can be a nightmare if a proper baffle and vibration control is not taken care of. This is the joy and pain of running an active system.

Having said that, I'm not going to say my particular xover points because it's not important given the context.

James Bang
03-11-2009, 11:59 AM
It's install and driver dependent. Due to speaker placement being limited, many opt for doors. Trying to cross a MB at 50hz can be a nightmare if a proper baffle and vibration control is not taken care of. This is the joy and pain of running an active system.

Having said that, I'm not going to say my particular xover points because it's not important given the context.

x2. it'll depend on your speakers limits and capabilities, and also it's location. the midrange and sub you'll match the midbass with should factor in on the xover points as well.

If I have to go passive, i'll aim for bi-amp capable xovers with tweet attenuation +3,0,-3db. The reason is so that I can balance between the tweet and mid by bi-amping, and I can balance left and right tweet using the attenuation jumpers.

I would use a 4 channel to bridge the mids as well so you can use gains to balance L+R mids. Balance on the HU can be used for the tweets as well.

bi-amp, attenuation for tweets... sounds like those Illusion xovers I was selling, but payday is coming up so i guess I'll keep them :cool:

C3 Customs
03-11-2009, 12:19 PM
James, very well said, thank you for the input...

C3 Customs
03-12-2009, 09:24 AM
Any more input?

FoxPro5
03-12-2009, 09:31 AM
Any more input?

How about output?

If you double the power, you get another 3 dB.
If you factor in cabin gain/transfer function, you can get what seems to be another 3db.

If you don't "deaden" your doors you loose 3 dB.
If you don't significantly reduce the road noise (200hz) in the vehicle, you're competing with up to 100 dB in some very loud vehicles. For every 10 dB attenuation, the relative loudness is cut in half.
If you don't make a proper baffle that converts the majority of the interfering back wave to heat at the lowest frequency played by the driver, you can loose another 3 dB easily.

So where does that leave you?

C3 Customs
03-12-2009, 09:33 AM
How about output?

If you double the power, you get another 3 dB.
If you factor in cabin gain/transfer function, you can get what seems to be another 3db.

If you don't "deaden" your doors you loose 3 dB.
If you don't significantly reduce the road noise (200hz) in the vehicle, you're competing with up to 100 dB in some very loud vehicles. For every 10 dB attenuation, the relative loudness is cut in half.
If you don't make a proper baffle that converts the majority of the interfeering back wave at the lowest frequency played by the driver, you can loose another 3 dB easily.

So where does that leave you?

Good insight also, so if you have already deadened the doors, it comes down to tuning correct.

FoxPro5
03-12-2009, 09:41 AM
Good insight also, so if you have already deadened the doors, it comes down to tuning correct.

The speaker response will be different if you change the operating environment, right? (ie dead door = better FR). AES testing uses a large, flat baffle usually. Do YOU have a large, flat baffle in your car? So yes, if crossover pts vary due to install and are considered a part of tuning, trying to decide where and how to play a driver before all of that is kind of a waste of time.

I only say this because I see a lot of n00b's (for a lack of a better term) setting their system up in their head before they even hear the response...or deciding on the passband before hand.....which might lead to false expectations. Sure, you can get the ballpark down before, but it's not the real deal until you tune it.

So for someone to say "you should cross that speaker between 50-250 hz" is kind of silly to me. And relying on a speaker manufacturer to decide the passband response with a passive crossover in their lab is even more complicating, I think. In short, run active.

C3 Customs
03-12-2009, 09:45 AM
Fox, Thank you for your insight