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Discussion Starter · #1 ·
so I'm utterly disappointed with the level of output from the focal KRX3 3" midrange driver. When purchasing this set, I expected the 3" midrange to be the star of the show, but it doesn't really shine...

For the amount of money this set cost me I expected more.

On the positive side I'm thrilled with the tweeter and the 6.5" is pretty beefy.

I need to change up my setup. I was thinking of doing one of several things to improve the response from about 200hz up to 5.5-6khz.

Two options concerning quasi-active 4-way - Run the 3" midrange and tweeter passive and cross them over high-pass at 5khz, then either of these: use the focal 6.5" as a mid-range driver to cover 200hz-5.5khz and get 8" woofers to cover 60-200hz
OR more conservatively I could get a 4" or 5.25" midrange to cover about 250- 5khz, and run the focal 6.5" drivers from 250 on down to about 70hz

I also thought about simply removing the focal 3" midrange altogether, but I spent an awful lot of money on this set so I'm trying to think of ways to incorporate all three of the speakers. If using the 3" midrange is going to present problems for my front stage I'll try to find another use for them or sell them.
 

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Discussion Starter · #2 ·
quick add-on:

I have a memphis 3-way active crossover and two front-stage amps:

Alpine PDX 150.4 and a realm audio 600.2

The realm amp does 150x2 rms @ 4 ohms, 300x2 @ 2 ohms, 600x1 @ 4 ohms - I'm using it to drive the focal 6.5" midbass right now, obviously the gains are turned WAY down.

I have quite a bit of headroom with the amount of power I have on tap - if I actually use every available watt it's 1200wrms for a front stage.
 

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Run active and your problems you'll be solved provided you can tune it correctly. This isn't a midrange issue, its a level issue which can be solved if you can adjust the levels of all the speakers.

A simple trick can be adding L-pads to the tweeters to attenuate to taste. This won't solve the efficiency advantage of the midbass, but it should remove the edgy sound caused by a hot tweeter. This is a very cheap solution and may be all you need. You can also add L-pads to the woofers, but padding down woofers is something you never really want to do as you want all the power you can get for midbass and sub frequencies.
 

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Discussion Starter · #4 ·
Run active and your problems you'll be solved provided you can tune it correctly. This isn't a midrange issue, its a level issue which can be solved if you can adjust the levels of all the speakers.

A simple trick can be adding L-pads to the tweeters to attenuate to taste. This won't solve the efficiency advantage of the midbass, but it should remove the edgy sound caused by a hot tweeter. This is a very cheap solution and may be all you need. You can also add L-pads to the woofers, but padding down woofers is something you never really want to do as you want all the power you can get for midbass and sub frequencies.
I'm running 3-way active already. The problem is that if I turn the midrange drivers up any more than they already are they start distorting. I have them crossed at 300hz and they STILL don't like it when I crank it up.

I have no problem with the tweeters - they sound exactly the way I want them to sound currently.

I'm running the tweeters and midranges off an alpine pdx 150.4 - that's 150wrms to each speaker, so I have the gains set very low.
I'm running the realm audio 600.2 to the 6.5" midbass woofers, gains also set very low.
 

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I'm running 3-way active already. The problem is that if I turn the midrange drivers up any more than they already are they start distorting. I have them crossed at 300hz and they STILL don't like it when I crank it up.

I have no problem with the tweeters - they sound exactly the way I want them to sound currently.

I'm running the tweeters and midranges off an alpine pdx 150.4 - that's 150wrms to each speaker, so I have the gains set very low.
I'm running the realm audio 600.2 to the 6.5" midbass woofers, gains also set very low.
Im sorry I misunderstood you.

Can you describe the distortion? Is it caused by over excursion of the midrange or does it simply sound compressed and lacks dynamics? The former is caused by too low of a crossover point and/or an inadequate enclosure, while the latter not enough power (which I really doubt, unless the midrange is very insensitive.

Have you tried raising the high pass for the midrange? A 3 inch not being able to reproduce 300hz is highly disturbing to me, but I guess you can try raising it see if it helps. How is it installed? Sealed? IB?

Are you sure you aren't pushing them TOO loud? Hearing loss is a real thing and I would be very careful that you aren't exposing yourself to dangerous levels.
 

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Also are you sure your not over powering KRX3's a bit. What are the levels set at on the Crossover, What, if any EQ'ing are you using. Also how are they installed and where?
 

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Discussion Starter · #7 · (Edited)
Im sorry I misunderstood you.

Can you describe the distortion? Is it caused by over excursion of the midrange or does it simply sound compressed and lacks dynamics? The former is caused by too low of a crossover point and/or an inadequate enclosure, while the latter not enough power (which I really doubt, unless the midrange is very insensitive.
When I crank it they begin to sound inaccurate and sloppy. I don't know if I have the proper vernacular... They basically lose accuracy and detail and sound like crap. They extremely strained and resonant at certain frequencies and flat on others.

Have you tried raising the high pass for the midrange? A 3 inch not being able to reproduce 300hz is highly disturbing to me, but I guess you can try raising it see if it helps. How is it installed? Sealed? IB?
They're in the plastic enclosures included with the set and mounted in the corners of my dash. I spread a thin (maybe 1/8") layer of clay on the inside of the back wall of the enclosures to help damp them. This is temporary until I can get door pods planned out so the entire set can be mounted in the doors.

Are you sure you aren't pushing them TOO loud? Hearing loss is a real thing and I would be very careful that you aren't exposing yourself to dangerous levels.
I'm not sure what the objective threshold is for "too" loud, but my subjective criteria is the tingle in my ears :D

If, after listening at high levels, I feel tingling in my ears, then that's "too" loud.

This set has not produced that response, so for me it's not "too" loud.
 

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Discussion Starter · #8 ·
Read above post first, then response to this one, specifically the install area - dash corners in the focal-made pods.

Also are you sure your not over powering KRX3's a bit. What are the levels set at on the Crossover, What, if any EQ'ing are you using. Also how are they installed and where?
I'm absolutely overpowering this set. I have my gains turned way down, so they're not actually seeing all the available power, but they have plenty on tap. Intuitively, distortion and sound pressure level should have a linear correlation, but - as I understand it - you're suggesting that overpowering the speakers can cause this correlation to fail, and the speakers to distort at a lower level of db.

For EQ I'm using the 7-band PEQ on an eclipse CD5000 H/U.

To be more specific about my goal:
I'd like to play some really intense rock, with heavy power chords, and play it at extreme output levels. I want the mids to sound full, powerful, forceful, and the whole time remain unrelentingly accurate.
 

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For the amount of money this set cost me I expected more..

I need to change up my setup. I was thinking of doing one of several things to improve the response from about 200hz up to 5.5-6khz.
Two options concerning quasi-active 4-way - Run the 3" midrange and tweeter passive and cross them over high-pass at 5khz, then either of these: use the focal 6.5" as a mid-range driver to cover 200hz-5.5khz and get 8" woofers to cover 60-200hz
OR more conservatively I could get a 4" or 5.25" midrange to cover about 250- 5khz, and run the focal 6.5" drivers from 250 on down to about 70hz
I also thought about simply removing the focal 3" midrange altogether, but I spent an awful lot of money on this set so I'm trying to think of ways to incorporate all three of the speakers. If using the 3" midrange is going to present problems for my front stage I'll try to find another use for them or sell them
Again, I don't know how you have that KRX3 mounted...You have yet to state that...is it in a proper enclosure? Anyway, Again as I stated in your previous post, I thought larger drivers might be a better bet for you. 8's in the doors with a 5 1/4" in the kicks or something to that matter. I really think the Focal prodducts are nice but it seems you were quick with the credit card and now you are quick with the install and conclusions about the drivers. How much time have you spent on the install and tuning?
 

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Discussion Starter · #10 ·
Again, I don't know how you have that KRX3 mounted...You have yet to state that...is it in a proper enclosure? Anyway, Again as I stated in your previous post, I thought larger drivers might be a better bet for you. 8's in the doors with a 5 1/4" in the kicks or something to that matter. I really think the Focal prodducts are nice but it seems you were quick with the credit card and now you are quick with the install and conclusions about the drivers. How much time have you spent on the install and tuning?
I said it twice already!!!!

lol :D The midranges are in the focal-supplied pods that come with the set - they're made of plastic and I damped the inside with a thin layer of clay.

I talked to orca (focal's distributor / tech support) and they said those pods are precisely the right size for those midranges. I guess I have to trust them on that.

The tweeters are also in these pods, and the 6.5" drivers are in my doors - they're mounted on MDF plates and have clay on the door behind them and several layers of dynamat extreme around the install area and two layers covering (almost entirely sealing) the door.

I was indeed quick with the credit card. I was hoping to avoid cutting my doors, so this set was the best route I could think of while still retaining my stock door skins. It appears that I'm not going to be happy unless I cut the doors anyway so I've accepted it as an inevitability now.
 

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They basically lose accuracy and detail and sound like crap. They extremely strained and resonant at certain frequencies and flat on others.
This could actually be a resonant enclosure. I have 6.5"s in fiberglass enclosures vented into the frame of the car. I have them highpassed at 300Hz with roughly 120-150 watts going to them. Initially I was getting resonance at lower midrange frequencies. I then used my amplifier to use an additional high-pass filter at 250Hz (the highest highpass setting on the amp) which made the highpass slope ultra steep (about 36db/octave @ 300Hz). This worked! It took many more steps in volume to get the resonance to come back, but I managed to drowned out (mask) the resonance by the overall volume of the sound. So, I suggest either damping the enclosure resonance or try a more steep highpass slope.
 

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Discussion Starter · #12 ·
This could actually be a resonant enclosure. I have 6.5"s in fiberglass enclosures vented into the frame of the car. I have them highpassed at 300Hz with roughly 120-150 watts going to them. Initially I was getting resonance at lower midrange frequencies. I then used my amplifier to use an additional high-pass filter at 250Hz (the highest highpass setting on the amp) which made the highpass slope ultra steep (about 36db/octave @ 300Hz). This worked! It took many more steps in volume to get the resonance to come back, but I managed to drowned out (mask) the resonance by the overall volume of the sound. So, I suggest either damping the enclosure resonance or try a more steep highpass slope.
That's pretty clever. I'm going to crack open the enclosures and add a little bit more clay, and toss another crossover on them to see what happens.

Also, as an added bonus that I completely forgot about until now.... I have a $650 set of 6.5" midranges sitting in my garage. Yep, those morel supreme carbon fiber mids I was selling here a while back... I decided to keep them - that may turn out to be a great decision :D
 

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That's pretty clever. I'm going to crack open the enclosures and add a little bit more clay, and toss another crossover on them to see what happens.

Also, as an added bonus that I completely forgot about until now.... I have a $650 set of 6.5" midranges sitting in my garage. Yep, those morel supreme carbon fiber mids I was selling here a while back... I decided to keep them - that may turn out to be a great decision :D
I wouldn't give up on the 3" mid just yet. There is still an option to try a 350Hz or 400Hz highpass instead of 300Hz. I've been worried about whether a 3" could work in the A-pillar with a 300Hz highpass. I got a bit paranoid about whether it could due to my 6.5" Infinities giving the fiberglass enclosure funky resonance. I bet a 4" or 4.5" mid would work out for my future A-pillar plans. Your 3" mid could be a bit of a guinea pig for me.:D
 

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Discussion Starter · #14 ·
I wouldn't give up on the 3" mid just yet. There is still an option to try a 350Hz or 400Hz highpass instead of 300Hz. I've been worried about whether a 3" could work in the A-pillar with a 300Hz highpass. I got a bit paranoid about whether it could due to my 6.5" Infinities giving the fiberglass enclosure funky resonance. I bet a 4" or 4.5" mid would work out for my future A-pillar plans. Your 3" mid could be a bit of a guinea pig for me.:D
lol. I guess I could try an even higher high pass, but with my 6.5" midbass drivers playing up that high won't it split the stage and sound ****ty?

My eventual plan is to put everything in the door, but I want to get driver choice sorted out before I start building.
 

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lol. I guess I could try an even higher high pass, but with my 6.5" midbass drivers playing up that high won't it split the stage and sound ****ty?
That's one of those things that you cannot possibly know for sure until you try but, yes, from what I've read on this forum, 200Hz - 300Hz is where you want to be and really no higher. Heck, 300Hz is sort of over the mark according to some on this forum. However, it never hurts to test something out and give it a listen. I try not to rule out skirting the edge, especially when I'm trying to eeek out that last bit of distortion-free output.

My eventual plan is to put everything in the door, but I want to get driver choice sorted out before I start building.
Yeah. The smaller driver is going to be preferrable due to it's on-axis dispersion being superior across the frequency range you're intending. So, trying to make that smaller driver work is the best idea. Only ditch it if you can't get it to work. Personally, I would keep stepping up to the next higher size until I got a driver that worked, that way I could keep the dispersion as ideal as possible.
 

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Discussion Starter · #16 ·
That's one of those things that you cannot possibly know for sure until you try but, yes, from what I've read on this forum, 200Hz - 300Hz is where you want to be and really no higher. Heck, 300Hz is sort of over the mark according to some on this forum. However, it never hurts to test something out and give it a listen. I try not to rule out skirting the edge, especially when I'm trying to eeek out that last bit of distortion-free output.



Yeah. The smaller driver is going to be preferrable due to it's on-axis dispersion being superior across the frequency range you're intending. So, trying to make that smaller driver work is the best idea. Only ditch it if you can't get it to work. Personally, I would keep stepping up to the next higher size until I got a driver that worked, that way I could keep the dispersion as ideal as possible.
I didn't know smaller drivers had better dispersion... If that's the case, then crossing my 6.5" midbass drivers up to 400hz is going to absolutely destroy my staging/imaging... they're mounted in the stock locations and fire directly into my left leg lol.

Once I fabricate door pods dispersion won't be an issue as I'll have the ability to point all speakers except the midbass directly at my ears.
 

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I didn't know smaller drivers had better dispersion... If that's the case, then crossing my 6.5" midbass drivers up to 400hz is going to absolutely destroy my staging/imaging... they're mounted in the stock locations and fire directly into my left leg lol.

Once I fabricate door pods dispersion won't be an issue as I'll have the ability to point all speakers except the midbass directly at my ears.
At lower frequencies, larger drivers have decent dispersion, it's at the higher frequencies where you get problems with them. So, the only reason to worry about the highpass is the quality of the sound at lower highpass frequencies. With a 6.5" midrange, 300Hz shouldn't be an issue. For a 3" midrange, it's not always going to work out if you want a strong/loud output. The extra highpass and steeper slope is the only trick I know that might get you a bit more output. Otherwise if all you have is the 6.5", then try to angle it on-axis to improve the higher frequencies.
 

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Discussion Starter · #19 ·
If I'm going to crossing the 6.5" speakers higher, like up to 400hz, won't that adversely affect their ability to handle power and play loud all the way down to 60 hz?

Should I get an 8" bass-only driver?
 
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