# Setting midrange/midbass frequencies



## rightguard07 (Jun 29, 2006)

I was wondering if its possible to run a midrange/midbass speaker (like the dynaaudio M160GT's) at a large frequency range like 70 Hz to 3 Hz to get the mid bass out of it and the mid range. I want to have that nice mid bass sound in the front as well as mid range but i dont want to have 2 seperate speakers for it. Has anybody did such a large frequencies on one speakers for midbass/midrange and how was the quality?


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## chuyler1 (Apr 10, 2006)

From Dynaudio's site...

_The MW160GT is a medium sized woofer designed for 2-way installations and may be combined with a subwoofer in a high quality 3-way system.

Due to the combination of smooth frequency response and excellent dispersion, this driver makes it possible to design a 2-way system with a clear and detailed midrange as well as a strong and powerful bass response.

Frequency response: 55Hz - 3.5kHz;
88 dB sens.; 130 watts continuous power handling._

So if Dynaudio says its ok, I don't see why it shouldn't work for you. If you wanted them to play down to 40-50Hz then there might be a problem, but I have done 2-way systems that sound great with a 70-80Hz HP point. Any lower and the low end distortion will start to affect your midrange.


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## rightguard07 (Jun 29, 2006)

Thanks chuyler for the info

Well I wont need it to play that low because I will have subs in the back playing the lower frequencies. But I wanna be able to run that nice midbass midrange sound up front too. So I guess I can try it. Anybody else here have experience with these speakers or similar doing this type of setup?


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## mvw2 (Oct 2, 2005)

At some point, you'll end up using way to much EQing to get lower bass and you'll start bottoming out the woofer as well. Playing around a bit, you'll figure out what what woofer is capable, both how low it can go and how loud it can get playing down that low.

An example is my woofer. I've run it full range and x-overed it as low as 50Hz with a sub. With a good amount of EQing on the bottom end, it can play quite low. However, it's not very happy doing so. When you start to push the driver, sound becomes less clean and may start to get muddy or distort. At some point further, it will start bottoming out. It's kind of mix of how low and how loud you want it to get. The lower you force it to go, the quieter your maximum volume will be before distortion/bottoming. 

Lower notes require more air volume movement. This either comes from cone size(large 10", 12", 15" subwoofers) or from excursion(Xmax - linear / Xmech - physical, non-linear limit). Small woofers like your mids have to make up for cone size with excursion. You only have so much available, and not all of it is linear(clean sounding). You're bound by the laws of physics. You will hit limits and start making compromises/trade-offs.

I wouldn't expect 70Hz to come easy to that woofer. I like to use the resonance frequency, Fs, as a rough indicator of what a speaker play down to easily. Basically I take 2 x Fs and get my high pass frequency, or at least a good starting point. For example, your 5.25"(I assume by specs) woofer has a Fs of 60Hz. It's resonance frequency is 60Hz. 2 x 60 = 120Hz. 

This is a good starting point for where it should be crossed over. I would be able to play very loud and clean at this point and frequency response is probably still pretty flat and linear, requiring little or no EQing.

As you move down lower, frequency response drops off, and you're forced to EQ in more midbass to keep the dB level flat as you push the driver to play lower. You run it at a 100Hz, then at 80Hz, and finally at 70Hz where you want it. By this point, you've probably added a ton of EQing. With my 6.5" woofer, I personally would have about a +15dB boost around this area just to bring up to par with the higher frequencies. Yours would probably be similar down this low. As well, you're really making the cone move a lot at louder volumes, so much so that you'll start to notice the woofer bottom out even at midrange volume levels. With so much required excursion to output the desired dB level at this low of frequency, you are now forced to play the system at quieter volumes to keep from damaging the woofer. The major EQing the volume limit is your trade-off. However, the woofer _can_ play down to 70Hz...if you really wanted it to.

I myself couldn't see that sacrifice or even the desire to put my speaker in harms way. Mine is set at around the 2 x Fs frequency for mine, around 125Hz. I've toyed with x-over points from 50Hz to 200Hz. I stuck at "compromise" points between 80Hz and 100Hz. In the end, I keep the driver happy and within its usable range. The benifit is clean, loud, and natural sound with very little EQing. My trade-off is a little less midbass up front. I can live with that.

You just have to figure out what trade-offs you're willing to take and what you can live with in the end.


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## mvw2 (Oct 2, 2005)

I'll note their frequency response tests were done in an optimally tuned enclosure. This is why it "seemingly" can go so low. Just thought I'd point that out as they do say it on their site.


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## rightguard07 (Jun 29, 2006)

Well If I did then Id have to set my sub up to about 130Hz and down to keep from having skipped frequencies. Is that low enough to set a subs LPF at? And I dont want like amazing bass in the front. I will have subs for that, but I want to have a nice little kick up front like you hear in the newer standard premium sound system cars.

And I was just pulling those frequencies outta my ass. I just through them in for a general idea how large of a range I am trying to get out of a single speaker


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## rightguard07 (Jun 29, 2006)

Would I be able to actively set my dyna audios from 120Hz to about 2 KHz? Or is that too large of a range for an active crossover or a crossover from my HU?


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