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In my pickup truck I’m planing to install gb25 in dash corners firing straight at windshield along with gb10 in sails and gb60 in kicks.
Would the gb25 cause problems like comb filtering and other reflection related issues?
I use to use the same location with morel elates 3 way with dome midrange and ms8 and did sound awesome with wide detailed stage.

Thanks
 

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What vehicle is this? I have a 16 silverado with wideband in the same spot and I dont like the sound. So I'm moving everything to the pillars
 

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In my pickup truck I’m planing to install gb25 in dash corners firing straight at windshield along with gb10 in sails and gb60 in kicks.
Would the gb25 cause problems like comb filtering and other reflection related issues?
I use to use the same location with morel elates 3 way with dome midrange and ms8 and did sound awesome with wide detailed stage.

Thanks
Sorry this isn't really on topic but could you tell me what caused you to switch from the elates to the frogs by chance? I'm currently debating the two sets right now. I'd be interested in what truck it is as well.

Hope you get your answer though and I'd be interested in what your impressions are after the switch if you go forward with it.
 

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In my Tundra I have Aurasound 2” Whispers in the dash factory tweeter locations and it sounds great to me.
 

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this is all going to be car dependent. Like one car we have in the shop right now, needs very minimal eq with the mids in the dash and the staging is great. Meanwhile, a Tesla Model S is a horrible recipient for a dash located speaker due to the massive (deep and wide.. lol) dip it causes centered at about 2.5k. Itll look like your mid is low passed at 1000hz.
 

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There is a Tundra that competes with 4" Morel Hybrid Integras in the factory dash locations and does very well.

There will be comb filtering but the frequency in which the first big null is at will depend on the distance to the windshield. The closer it is to the windshield the higher up in freq the null will occur. There are other factors that will affect it too like the polar response of the driver.

Someone posted a formula on here for it (I think Patrick Batemen) and when I plugged the numbers into it for my cars geometry the null occurred dead nuts where the formula said it would.

My current setup has the null at 4.5khz but I'm crossing over to a tweeter in the sail at 3khz so no big deal especially after some pre-xover out-of-passband eq work to smooth it out.
 

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I had a couple previous Audi's, where I had a GB25 in the dash, firing upward into the windshield... sounded fine.
 

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If you had the option to use the corner of the dash but angle the drivers to be more on-axis, would this be better?

I'm thinking they would be firing almost parallel to the windscreen...
 

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I seem to remember reading a paper on how firing a speaker parallel to the windshield is worse then firing it right into it. It also discussed how the distance your dash speaker is from where your dash and windshield meet matters. Per the paper I believe that distance is equal to the diameter of the speaker.

There is a post on the forum that links to the paper. It was cool read, and as you can see I clearly committed it all to memory....
 

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I thinking you'll be fine firing up at the glass in a Tundra. Works great in an 09 and up Ram too.
 

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this is all going to be car dependent. Like one car we have in the shop right now, needs very minimal eq with the mids in the dash and the staging is great. Meanwhile, a Tesla Model S is a horrible recipient for a dash located speaker due to the massive (deep and wide.. lol) dip it causes centered at about 2.5k. Itll look like your mid is low passed at 1000hz.

I'm having the same problem... I have a Chevy Colorado crew cab and have a hell-ofa-time trying to get my mids in the factory dash locations to sound correct.

I'm a slow learner... cause i've tried GB25's, Illusion Audio C3CX, Infinity Kappa300, and my current Stereo Integrity M3's... I have the huge dip at 2500, and yes, its looks like LP is set at 1000hz. All the different speakers behave about the same at that 2500hz. I've tried a multitude of cross over settings .. from 2500 thru 7000hz (depending on the speaker) I just cant seem to figure it out.

I've been using the Jazzy speaker curve excel and pink-noise REW-RTA with the AudioFrog soundcard and mic.... the down slope on the mids curve always falls off way to fast, so never get a chance to do much eq'ing there..

What did you do to fix the prob in the 'Tesla Model S' mids?
 

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I'm having the same problem... I have a Chevy Colorado crew cab and have a hell-ofa-time trying to get my mids in the factory dash locations to sound correct.



I'm a slow learner... cause i've tried GB25's, Illusion Audio C3CX, Infinity Kappa300, and my current Stereo Integrity M3's... I have the huge dip at 2500, and yes, its looks like LP is set at 1000hz. All the different speakers behave about the same at that 2500hz. I've tried a multitude of cross over settings .. from 2500 thru 7000hz (depending on the speaker) I just cant seem to figure it out.



I've been using the Jazzy speaker curve excel and pink-noise REW-RTA with the AudioFrog soundcard and mic.... the down slope on the mids curve always falls off way to fast, so never get a chance to do much eq'ing there..



What did you do to fix the prob in the 'Tesla Model S' mids?
Boosted just enough to not clip the signal. Boosting will depend on what processor you have and how the gain structure is set up

Sent from my SM-G975U using Tapatalk
 

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Boosted just enough to not clip the signal. Boosting will depend on what processor you have and how the gain structure is set up

Sent from my SM-G975U using Tapatalk

I have the Helix DSP PRO and a Mosconi-D2-Amp (105 watts per channel) running my tweets and mids.

I have the Tweet gains set at about 20% and the mid gains at about 30%, should I change that??
 

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Boosted just enough to not clip the signal. Boosting will depend on what processor you have and how the gain structure is set up

Sent from my SM-G975U using Tapatalk
Did you boost Freq's in the EQ, or boost mids-gain on the amp, or boost the mids-gain in the DSP?....
 

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Not every situation is the same but I found boosting a null created by a destructive interference from a reflection (like dash mids off a windshield or door midbass off a console) usually does not produce a favorable outcome. Though the RTA may show a slight improvement with lots of boost the sound will become strained - less effortless.

If there is anyway to at least tilt the driver under the grill or some other method so that it physically gets closer to the surface it's reflecting off - this will push the null up in the freq response and hopefully into another driver's passband (tweeter).


Here is the formula Patrick Bateman (John) posted that I mentioned earlier:

Start of Null Freq range = Speed of Sound (13500" per sec) / distance to reflective surface / 4
https://www.diymobileaudio.com/forum/3140314-post12.html

Here is the technical paper Souths1der mentioned above on dash speaker placement:
https://www.jjracoustics.com/129_AES-2010.pdf
 

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I'm having the same problem... I have a Chevy Colorado crew cab and have a hell-ofa-time trying to get my mids in the factory dash locations to sound correct.

I'm a slow learner... cause i've tried GB25's, Illusion Audio C3CX, Infinity Kappa300, and my current Stereo Integrity M3's... I have the huge dip at 2500, and yes, its looks like LP is set at 1000hz. All the different speakers behave about the same at that 2500hz. I've tried a multitude of cross over settings .. from 2500 thru 7000hz (depending on the speaker) I just cant seem to figure it out.

I've been using the Jazzy speaker curve excel and pink-noise REW-RTA with the AudioFrog soundcard and mic.... the down slope on the mids curve always falls off way to fast, so never get a chance to do much eq'ing there..

What did you do to fix the prob in the 'Tesla Model S' mids?
Trying to fix the issue by swapping speakers isn't going to work well. The issue is the geometry of the speaker location to the windshield and other surfaces, you can swap speakers every day and still have issues at around the same frequency. Some EQ may help, but like Truthunter said, fixing nulls that are caused by a speaker's distance to a particular surface can be difficult, and sometimes impossible to fix with EQ. To fix the problem, you'll want to find a different place to install the speaker.
 

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Not every situation is the same
This, so i really cant help you guys on what to eq or how..


but I found boosting a null created by a destructive interference from a reflection (like dash mids off a windshield or door midbass off a console) usually does not produce a favorable outcome. Though the RTA may show a slight improvement with lots of boost the sound will become strained - less effortless.
this depends. in the setup we were using there was still plenty of gain to take advantage of so instead of just adding gain and cutting everything else, we just boosted. No difference in one method or the other. On top of that, we were boosting in the top end of what the driver plays, where there is much less content and much harder to cause the signal to clip. I know 2 others with the same car, with the exact same speakers and same processor that had to work around this and had a favorable outcome after flattening the response.
 
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