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Chaotic_Thought
01-06-2012, 10:38 PM
I have some unknown model CDT comps in the doors of my 03 F150 ext cab. When sitting in a normal driving position, the midbass response is rather lackluster. However if i move my head more towards where the head unit sits in the dash, the midbass response improves dramatically. Now i know i am moving more on axis to the drivers, and that the doors are not deadened, but what can be done to move the midbass focus higher in the cab?

mylows10
01-06-2012, 10:52 PM
deaden the doors or make pods ,i run cdt also and mine sound nice

Chaotic_Thought
01-06-2012, 11:04 PM
deaden the doors or make pods ,i run cdt also and mine sound nice

Though i appreciate the input, you didn't really answer the question put forward. I acknowledged that the doors are not deadened and asked if there was an alternative to move the focus up.

CHEMMINS
01-06-2012, 11:05 PM
He gave you both answers you needed. Either deaden the doors or reposition them with pods.

Chaotic_Thought
01-06-2012, 11:08 PM
He gave you both answers you needed. Either deaden the doors or reposition them with pods.

So basically those 2 are the only conceivable options?

mylows10
01-06-2012, 11:10 PM
well you could make mounting rings for them and just make one side of the rings wider than the other to point them in the direction you want

Why So Cereal?
01-06-2012, 11:11 PM
I have some unknown model CDT comps in the doors of my 03 F150 ext cab. When sitting in a normal driving position, the midbass response is rather lackluster. However if i move my head more towards where the head unit sits in the dash, the midbass response improves dramatically. Now i know i am moving more on axis to the drivers, and that the doors are not deadened, but what can be done to move the midbass focus higher in the cab?

So, basically what you are saying is that the midbass is weak in one position and stronger when you move around....AND you want a higher stage?

Firstly, with the midbass, what youre experiencing is cancellation from phasing issues. To be sure, fade all of the sound to one side on your HU and if the midbass is better than with the 2, its cancellation. If you have Time Alignment on your HU, this will help. But if you do not, swap the pos and neg (phase) on one of the drivers and see if it improves, if not, swap it back and try the other.

Chaotic_Thought
01-06-2012, 11:15 PM
So, basically what you are saying is that the midbass is weak in one position and stronger when you move around....AND you want a higher stage?

Firstly, with the midbass, what youre experiencing is cancellation from phasing issues. To be sure, fade all of the sound to one side on your HU and if the midbass is better than with the 2, its cancellation. If you have Time Alignment on your HU, this will help. But if you do not, swap the pos and neg (phase) on one of the drivers and see if it improves, if not, swap it back and try the other.

Ahh yes. I have faded from side to side, but still with the same effect. I am running the 880 and have tried all sorts of T/A and crossover combinations and nothing really seems to help. With it faded to either side, I am still getting poor midbass at normal driving position but the on axis response is much better. I know that the stock location is far from optimal, but i though midbass wasn't as directional and didn't need to be mounted on axis.

What are the chances that it is the cheaper CDT's that are causing the issue?

Rich B
01-06-2012, 11:15 PM
well you could make mounting rings for them and just make one side of the rings wider than the other to point them in the direction you want

Like this......

http://thumbs2.ebaystatic.com/m/mblcvUulsbY6dTAJXD2saNQ/140.jpg

Angled MDF speaker ring pair, 6.5" NEW | eBay (http://www.ebay.com/itm/Angled-MDF-speaker-ring-pair-6-5-NEW-/180738548401?pt=LH_DefaultDomain_0&hash=item2a14db62b1)

TaylorFade
01-06-2012, 11:21 PM
Where do you have them crossed? And how much power are you giving them? You don't get "height" from midbass. Width, maybe. Height is waaaay out of MB range.

If it sounds better when you move your head to the center, I don't see why T/A wouldn't help that. Maybe you need to revisit your settings. But definitely try reversing the polarity too.

Why So Cereal?
01-06-2012, 11:29 PM
Ahh yes. I have faded from side to side, but still with the same effect. I am running the 880 and have tried all sorts of T/A and crossover combinations and nothing really seems to help. With it faded to either side, I am still getting poor midbass at normal driving position but the on axis response is much better. I know that the stock location is far from optimal, but i though midbass wasn't as directional and didn't need to be mounted on axis.

What are the chances that it is the cheaper CDT's that are causing the issue?

Well, midbass is localized by arrival time at your ears so, with proper T/A and install, I would think most any location could work. Aiming is important but not as much as a tweeter or so IMO.

Anywhoo, the main thing that makes me think cancellation is that you said it improves dramatically if you move your head to the center of the car. Whether or not the drivers are on axis or not wont affect the volume of the midbass freqs. In the higher freqs were beaming occurs is where on/off axis becomes a problem usually. You say youve tried playing with the T/A, though. You could still try flipping the phase on one driver, but, I'm not even too sure that would fix it but its free to try.

Do you run a sub? or rear speakers?

Chaotic_Thought
01-06-2012, 11:31 PM
Where do you have them crossed? And how much power are you giving them? You don't get "height" from midbass. Width, maybe. Height is waaaay out of MB range.

If it sounds better when you move your head to the center, I don't see why T/A wouldn't help that. Maybe you need to revisit your settings. But definitely try reversing the polarity too.

Well sadly the whole setup so far has been a bit of a hassle. And the thread i had started on the subject has vanished.

Basically with all head unit settings being flat and balanced, no TA, one side will bottom out before the other. I have tried swapping channels, changed RCA's, among other things and can't solve the issue. I am starting to think the preouts on my 880 are bad. I need to put a DMM to the preouts to see if they are varying from the other.


Well, midbass is localized by arrival time at your ears so, with proper T/A and install, I would think most any location could work. Aiming is important but not as much as a tweeter or so IMO.

Anywhoo, the main thing that makes me think cancellation is that you said it improves dramatically if you move your head to the center of the car. Whether or not the drivers are on axis or not wont affect the volume of the midbass freqs. In the higher freqs were beaming occurs is where on/off axis becomes a problem usually. You say youve tried playing with the T/A, though. You could still try flipping the phase on one driver, but, I'm not even too sure that would fix it but its free to try.

Do you run a sub? or rear speakers?

No sub as of yet. I am in the process of building a center console to house a Dcon powered by most likely a Skar 800.1. I have the rears defeated by the head unit. With the rears playing i was getting very obvious cancellation. As in if i moved the fade from full forward to 0 what bass i had would start to disappear all together.

TaylorFade
01-06-2012, 11:36 PM
Maybe one is blown?

mylows10
01-06-2012, 11:41 PM
Maybe one is blown?
if so ,i have some replacements for you .$$$$

Chaotic_Thought
01-06-2012, 11:46 PM
Maybe one is blown?

Unlikely. Swapping outputs from the head unit will swap the side that pops. I just need to track down if it is the amp causing the problem or the head unit. The amp is a cheap crunch 5000.1


if so ,i have some replacements for you .$$$$


Hah my wife still is unhappy that i dropped $125 on 1/0 out of the blue.

Why So Cereal?
01-06-2012, 11:48 PM
still wouldnt explain why you get better midbass when you move your head....

Chaotic_Thought
01-06-2012, 11:56 PM
I will try and see how it picks up on a mic tomorrow and maybe it will make more sense.

keep_hope_alive
01-06-2012, 11:59 PM
They are in phase if midbass increases when You are equidistant from both, I.e. in the middle.

I agree that deadening willh help, and sealing the door openings and adding proper seals is crucial for midbass. In your seat you are hearing the front and back wave at the same time (due to lack of seals) so you don't hear midbass. To obtain good midbass Sealing your doors is #1 and #2. That is seal the door openings and seal around the speaker. Deadener is #3.

Having T/A will help as well. You are a different distance from each. That difference results in cancellation.

Chaotic_Thought
01-07-2012, 12:02 AM
They are in phase if midbass increases when You are equidistant from both, I.e. in the middle.

I agree that deadening willh help, and sealing the door openings and adding proper seals is crucial for midbass. In your seat you are hearing the front and back wave at the same time (due to lack of seals) so you don't hear midbass. To obtain good midbass Sealing your doors is #1 and #2. That is seal the door openings and seal around the speaker. Deadener is #3.

Having T/A will help as well. You are a different distance from each. That difference results in cancellation.

Would door pods negate the need for deadening since a pod would be acting as the enclosure?

perfecxionX
01-07-2012, 12:04 AM
Would door pods negate the need for deadening since a pod would be acting as the enclosure?

yes. Like he said, you need to seal the holes in your doors with something rigid ( i use deadener on top of thin sheet aluminum). The deadener adds mass to the door panels to prevent vibrations and rattles. That probably wont be an issue with kick pods so you probably wont need deadener on the doors.

Why So Cereal?
01-07-2012, 12:04 AM
They are in phase if midbass increases when You are equidistant from both, I.e. in the middle.

I agree that deadening willh help, and sealing the door openings and adding proper seals is crucial for midbass. In your seat you are hearing the front and back wave at the same time (due to lack of seals) so you don't hear midbass. To obtain good midbass Sealing your doors is #1 and #2. That is seal the door openings and seal around the speaker. Deadener is #3.

Having T/A will help as well. You are a different distance from each. That difference results in cancellation.

listen to this guy OP, great dude, I love the way my system sounds now and alot of the ideas I got and the installing tips I received were from K_H_A

mylows10
01-07-2012, 12:05 AM
if they are enclosed then i would say yes,but they would have to have some area as an enclosure of some sort

Chaotic_Thought
01-07-2012, 12:08 AM
Typically what is the air space you would need for a single 6.5?

Why So Cereal?
01-07-2012, 12:09 AM
Would door pods negate the need for deadening since a pod would be acting as the enclosure?

the thing to worry about here would be enclosure volume. Car audio midbass drivers are designed to perform IB, so a simple pod wont perform as well as a sealed door. You can maybe make pods work, but you'll need a good bit of power to get the same amount of output you would in your door IB and that still may not yield the same results.

keep_hope_alive
01-07-2012, 12:14 AM
Yea, door pods are not always sealed enclosures, just rings like pictured above. As long as the speaker uses the door for airspace, the doors should be sealed. It's akin to holding a woofer in your hand and playing it, you don't hear bass because the front and rear waves cancel. The enclosure isolates the front and rear wave. Allowing you to hear just one. The result is midbass. True for home, pro, and car audio.

Over the past two decades I have heard a lot of complaints that the aftermarket speakers have less bass than factory. The cause is always seals. The factory speaker will perfectly seal against the door panel, essentially using the door panel as the front baffle. Airtight is the key. I put foam on the front and rer of every door speaker to recreate those seals.

Chaotic_Thought
01-07-2012, 12:15 AM
it could, but the thing to worry about here would be enclosure volume. Car audio midbass drivers are designed to perform IB, so a pod, if not large enough, wont perform as well as a sealed door. You can make smaller pods work, but you'll need a good bit of power to get the same amount of output you would in your door IB and that still may not yield the same results.

My issue with deadening the doors is i do not plan on having the truck too terribly long, maybe 2 years at the most before i get something new. With the center console i can either sell it with the truck for a added fee or i can sell it to someone on craigslist to recover atleast a tiny portion of the cost. Same for door pods. Deadening however, would be staying with the truck and i wouldn't see any of that money back. Cost efficiency my friends.

I may just have to bite the bullet on this one and spend the cash on some deadening.

Why So Cereal?
01-07-2012, 12:19 AM
My issue with deadening the doors is i do not plan on having the truck too terribly long, maybe 2 years at the most before i get something new. With the center console i can either sell it with the truck for a added fee or i can sell it to someone on craigslist to recover atleast a tiny portion of the cost. Same for door pods. Deadening however, would be staying with the truck and i wouldn't see any of that money back. Cost efficiency my friends.

I may just have to bite the bullet on this one and spend the cash on some deadening.

shouldnt be terribly expensive...you could just get some sheet metal or some wood and cover those holes. Audio Technix makes some nice budget deadener you could use.

keep_hope_alive
01-07-2012, 12:19 AM
Dude, two years? Long enough to do it right. :)

Start with foam seals around the speaker. $6 investment.

TaylorFade
01-07-2012, 12:24 AM
I just made a tiny enclosure for mine. And I mean tiny. It's sealed though and has good output. Needs some power though. Also put some non-hardening modeling clay on the ring to decouple and seal.



http://i848.photobucket.com/albums/ab45/taylorfade/183ac8db.jpg

http://i848.photobucket.com/albums/ab45/taylorfade/c33ae3cb.jpg

http://i848.photobucket.com/albums/ab45/taylorfade/3214ad5e.jpg

http://i848.photobucket.com/albums/ab45/taylorfade/ab1e993c.jpg

Chaotic_Thought
01-07-2012, 12:25 AM
Dude, two years? Long enough to do it right. :)

Start with foam seals around the speaker. $6 investment.

The real problem is budgeting it in, along with the 97 z71 restoration, remodel of a 90 year old house, 3 kids, wife, yadda yadda yadda.

keep_hope_alive
01-07-2012, 01:17 AM
I hear ya dude. Foam weatherstripping is my budget trick. I keep a box with a variety of widths and thicknesses on hand for installs.

VWBobby
01-07-2012, 01:18 AM
In the systems I've installed, I've always taken a little time to mount the speaker on-axis to the driver's ear. Sit in the vehicle and visualize what angle the speaker must be to be pointed straight at your ear or near the headrest. Use dowels or hold the speaker by hand (or a helper) and measure the offset on the large side. This will give you the thickness needed for the correct angle. I mount all speakers on axis and keep the tweeters and mid-ranges up high in the door.

Keeping the speakers on axis to the listener also has the advantage of not beaming or canceling out each other firing across the cabin head on. ;) Almost no time alignment is needed also.

keep_hope_alive
01-07-2012, 01:27 AM
Agreed! But aiming is advanced and requires permanent modifications and 20 hours or so, totally worth it though.

I keep my mids and tweets on-axis, midbass is still off axis but I will soon experiment with larger kicks and door pods.

VWBobby
01-07-2012, 11:51 AM
Exactly. I just thought of something I wasn't exactly correct about..... :wow: Some speakers actually work better off-axis because of the beaming effect. I was actually backwards in my post above. I read somewhere recently where they actually measured the sound through a narrow port at various angles and found some speakers beam a lot more head on or around 20 degrees compared to 45 or 60, lets say... :)

Pods are good for speakers that like sealed enclosures, makes a big difference. I've used some poly coned speakers that work well in pods on-axis. Right now I'm running some Aura 8's in door panels at rib cage height. They are on-axis to my ears and sound great, LPF'd at 500hz using a passive xover. I just cut some MDF rings and fiberglassed them in after hot-gluing dowels to hold the rings at the correct angle.

Honestly, I have about 5 hours into the whole project.

Chaotic_Thought
01-07-2012, 12:57 PM
On a positive side note, my 1/0 came in this morning.

trumpet
01-09-2012, 12:03 PM
I don't know what CDT mids you have but in my experience the CL-6 mids are very light on midbass impact. It helps immensely to reinforce those frequencies with a good subwoofer that can sound good playing bass guitar, kick drums, and so on.

Please don't build a sealed enclosure for your mids. While someone might get lucky and get good results, this is a bad idea. Use the door as the enclosure. I have a write-up on my site for how to do this or you can look up basically any experienced installer's build thread(keep_hope_alive, for example) to see ideas to accomplish this.

Two years is a long time to suffer a disappointing sound system. For less than $100 in materials you could treat both doors and get much better midbass without upgrading the speakers.

keep_hope_alive
01-09-2012, 06:04 PM
i agree that sealed door pods should only be done with speakers designed for such an install - i.e. raw drivers, not standard car audio components. my sealed pods will be for some Silver Flute 6.5's and i'll also experiment with Dayton Reference woofers. i'll measure the actual T/S and model the enclosures for adequate volume. I may also incorporate an aperiodic vent to the door cavity. i'd like to have a removable speaker baffle so i can try a variety of speakers without changing the actual pod. i did this in my kicks and it was very handy.

Why So Cereal?
01-09-2012, 06:17 PM
i agree that sealed door pods should only be done with speakers designed for such an install - i.e. raw drivers, not standard car audio components. my sealed pods will be for some Silver Flute 6.5's and i'll also experiment with Dayton Reference woofers. i'll measure the actual T/S and model the enclosures for adequate volume. I may also incorporate an aperiodic vent to the door cavity. i'd like to have a removable speaker baffle so i can try a variety of speakers without changing the actual pod. i did this in my kicks and it was very handy.

make sure to post up some results. i'm looking into both of those exact mids, and they will probably be in pods

VWBobby
01-09-2012, 11:19 PM
I'm tuned in for any results you have.:) A removable or block-able vent would be great to have for testing various drivers and still be able to adjust the 'enclosure'.

keep_hope_alive
01-09-2012, 11:31 PM
it will happen soon - i'm getting fed up of having brand new drivers sitting in boxes and not in my car. :furious:

but i plan on incorporating these in stages. i think the kicks will be done first - to accommodate anything 7" and smaller. then i'll run a kick midbass while i experiment more with full range 2" drivers at the apillar and dash. then i'll build the pods by taking the lower half of my door panel and making a decently large enclosure (considering) and I agree the door aperiodic vent should be removable. i typically use two speaker grills to sandwich fiberglass between - a wood circle could be fitted instead.

of course, i'll take more pictures than necessary and RTA everything. :)

VWBobby
01-10-2012, 10:09 AM
Sounds like a fun project. :) Just so you don't have to re-invent the wheel.....I'll tell you what BMW did to install the speaker systems in the Harmon-Kardon setups. 6.5" speaker down in the door near kick panel, 3" full range in door about 8" above driver/passenger lap area firing straight across the cabin. A set of tweeters up in the a-pillars. 6 more speakers for rear fill. Personally, I don't think the sound could be improved much - unless I replaced all the drivers with ones that have a natural roll-off that blends with the next speaker in the chain. It really does sound that good.:)

keep_hope_alive
01-11-2012, 04:00 PM
I have considered upper door mids in lieu of kick mids. I haven't heard one of those setups do two seats well. My goal is 2 seats with symmetric or minimal T/A

its_bacon12
01-11-2012, 06:24 PM
I have some unknown model CDT comps in the doors of my 03 F150 ext cab. When sitting in a normal driving position, the midbass response is rather lackluster. However if i move my head more towards where the head unit sits in the dash, the midbass response improves dramatically. Now i know i am moving more on axis to the drivers, and that the doors are not deadened, but what can be done to move the midbass focus higher in the cab?


Cars are an absolute nightmare when it comes to audio. Chances are you either are experiencing cancellation due to reflections or specific nodes in your car. The frequencies you hear when you move your head, but don't hear otherwise, are likely positive interference. Midbass seems about the right frequencies for that to happen, similar how bass experiences this in home environments.

hispls
01-11-2012, 06:59 PM
Lots of good suggestions here IMO. I would be shocked if you experimented with ALL of them and still weren't happy.

Also I don't think the equipment is the problem and throwing different mids in there would likely do little or nothing to solve what is clearly an accoustic problem with the vehicle and speaker locations.

zako
01-11-2012, 09:32 PM
I have some unknown model CDT comps in the doors of my 03 F150 ext cab. When sitting in a normal driving position, the midbass response is rather lackluster. However if i move my head more towards where the head unit sits in the dash, the midbass response improves dramatically. Now i know i am moving more on axis to the drivers, and that the doors are not deadened, but what can be done to move the midbass focus higher in the cab?

What you're observing seems like a symptom of a car with no time correction for the front midbasses. When you move your head to the center of the vehicle, the distance from your ears to your speakers is the same for each speaker, and so the speakers are roughly in an acoustic phase. When you move your head away towards the normal driving position, the speakers are a little out of phase. Low frequencies are the ones that are most affected by the phase issues. If you don't like it, buy a stereo or a processor with time correction. Pioneer is coming up with a unit that automatically tunes TA and equalizer soon, this may be worth looking into.

Some people also mentioning aiming your midbasses. My guess is that aiming midbasses differently will not affect the frequency response in the low frequencies, but it can affect the frequency response towards the upper frequency limit of the driver. All drivers experience a phenomenon called beaming, which basically reduces the dispersion of sound at the upper end of driver's limit. For 6.5 inch drivers this should start somewhere above of 2-3KHz, well above the midbass range.

Of course, all of this could be wrong and you are experiencing the work of some other sonic gremlins..