DiyMobileAudio.com Car Stereo Forum banner

1 - 20 of 75 Posts

·
Banned
Joined
·
1,808 Posts
Discussion Starter #1
Hi all,

I tried to search on google already, but, you know my search skillz are for poop, so forgive the question. If my tests tomorrow still show a huge 12db drop after 50Hz, it seems it would make sense to look for a low-shelf filter to cut frequencies starting at around 55Hz and lower. From my earlier tests it seems like a pretty consistent gain at 50Hz and below of around 12db. And that's a pretty steep slope at 50-60Hz to try and "tune" out with conventional high/low pass filter methods. I was thinking of trying to design a deep filter for a midbass that would compensate for this sharp acoustic slope. But then I started thinking about other types of EQ filters and remembered that a low shelf filter would be a pretty good way to treat this acoustical demon that haunts my Nissan Sentra. :mad:

I would like to know if there is a product available to allow for variable low shelf filtering. Or if there is a variable filter designed to combat cabin gain like mine. I think that could be useful for a lot of people who don't own or aren't ready to buy a pricey electronic sound processor. A simple active filter like this I figure wouldn't be hard to design and sell cheap.
 

·
Registered
Joined
·
675 Posts
SO for all of your truly scientific testing and in house calculating of various things...have you gone outside...completed your system...and just tuned it like the rest of us who actually go out and do things for real instead of just theorizing and so forth. Its amazing you haven't found anything on this because although this magical thing called cabin gain exists...most of us use it to our advantage. its not that big of a problem. Seriously..I'm not trying to be a big ass here other than to say...go finish your install quit messing with meters and Dmm's and go setup your system and just listen to it...you are over complicating the crap out of this...
But on a side note...the steepest shelve filters in a caraudio are ususally 24db/octave and a FEW 36...you could always go get a Lake Contour MESA or something like that for quite a few thousand G"s and do brick wall filters... But alas it is not needed..use the cabin gain...use that natural roll on and roll of of cabin gain. Our ears naturally need more bass response...dont get rid of it..use it to your advantage...dont chase your own tale when you don't know yet if the tale is bad or not..
 

·
Banned
Joined
·
1,808 Posts
Discussion Starter #5 (Edited)
SO for all of your truly scientific testing and in house calculating of various things...have you gone outside...completed your system...and just tuned it like the rest of us who actually go out and do things for real instead of just theorizing and so forth. Its amazing you haven't found anything on this because although this magical thing called cabin gain exists...most of us use it to our advantage. its not that big of a problem. Seriously..I'm not trying to be a big ass here other than to say...go finish your install quit messing with meters and Dmm's and go setup your system and just listen to it...you are over complicating the crap out of this...
But on a side note...the steepest shelve filters in a caraudio are ususally 24db/octave and a FEW 36...you could always go get a Lake Contour MESA or something like that for quite a few thousand G"s and do brick wall filters... But alas it is not needed..use the cabin gain...use that natural roll on and roll of of cabin gain. Our ears naturally need more bass response...dont get rid of it..use it to your advantage...dont chase your own tale when you don't know yet if the tale is bad or not..
Man, it is rather useless to ask questions here at this point. You guys obviously don't know what a shelf filter is for cripes sake and you're going to put me down?

Here is a shelf filter:


That is not a high-pass or a low pass. It's a SHELF! Jesus. If you guys don't know what you're talking about just don't post, and certainly don't criticize. I'm sick of your retardation. The DMM thread was just an example of you guys' stupidity and arrogance. I posted FACTS and detailed explanations to qualify my statements only to have them ignored and then watch as some dipshits try and mock me. Get a clue guys. If you don't know what someone asked, just please stay out of the thread!

And to talk about cabin gain, I want to use midbasses up front to augment frequencies at 60Hz to 100Hz so that the overall sound matches up with the cabin gain, but I STILL would need a bit of filtering on the lowest end and a shelf filter would be an ideal tool in this case.
 

·
Banned
Joined
·
1,808 Posts
Discussion Starter #7
Maybe you should take your own advice.
Maybe you should butt out.

Only on a forum like this would someone not get a straight answer and instead get insulted. This goes straight back to what I've said about "popularity". I'm not socially popular on this board, so people take cheap shots at me that aren't warranted nor are they useful to anyone else reading the threads. If you've got something to ADD to the thread that is useful, then by all means, add it. Otherwise just stay out of it.
 

·
(((((((In Stereo)))))))
Joined
·
1,330 Posts
I know damn good and well what a shelving EQ is.

It's useless in car audio since anyone who's seen an FR graph and trusts their 2 eyes knows that irregularities is FR come in peaks and dips. Not shelves.

If you speaker doesn't like playing that large a range, don't let it.


No a google search doesn't say "a shelving filter is useless in car audio" just like it doesn't say "getting kicked in the nuts real hard hurts real bad!"


What's up with the challenge?
 

·
Banned
Joined
·
1,808 Posts
Discussion Starter #9
I know damn good and well what a shelving EQ is.
You do now. I just showed you. In your earlier post you compared my question about a 'shelf' filter to a highpass filter. I think you are trying to make it look like you know more than I do about everything, but I don't think you do.

It's useless in car audio since anyone who's seen an FR graph and trusts their 2 eyes knows that irregularities is FR come in peaks and dips. Not shelves.

If you speaker doesn't like playing that large a range, don't let it.


No a google search doesn't say "a shelving filter is useless in car audio" just like it doesn't say "getting kicked in the nuts real hard hurts real bad!"


What's up with the challenge?
I have pretty good data that shows an acoustic response that looks pretty damn much like a fricken SHELF filter, so why the hell wouldn't I apply a shelf filter to fix it? Hmm? I guess logic and reason have escaped your narrow focus on trying to attack me. You're a douche and need to shut up.
 

·
(((((((In Stereo)))))))
Joined
·
1,330 Posts
I have pretty good data that shows an acoustic response that looks pretty damn much like a fricken SHELF filter, so why the hell wouldn't I apply a shelf filter to fix it? Hmm? I guess logic and reason have escaped your narrow focus on trying to attack me. You're a douche and need to shut up.
You're gonna have to come up with more than "pretty good data" to get a car audio company to design a product for one asshole, Mr. NumbersBoner.

If you really want, you may be able to adapt a recording EQ for use in the car if you'd rather do that than take some real advice.
 

·
Registered
Joined
·
675 Posts
Man, it is rather useless to ask questions here at this point. You guys obviously don't know what a shelf filter is for cripes sake and you're going to put me down?

Here is a shelf filter:


That is not a high-pass or a low pass. It's a SHELF! Jesus. If you guys don't know what you're talking about just don't post, and certainly don't criticize. I'm sick of your retardation. The DMM thread was just an example of you guys' stupidity and arrogance. I posted FACTS and detailed explanations to qualify my statements only to have them ignored and then watch as some dipshits try and mock me. Get a clue guys. If you don't know what someone asked, just please stay out of the thread!

And to talk about cabin gain, I want to use midbasses up front to augment frequencies at 60Hz to 100Hz so that the overall sound matches up with the cabin gain, but I STILL would need a bit of filtering on the lowest end and a shelf filter would be an ideal tool in this case.
Haha typical spence...I said the best shelf (meaning closest to a true shelf) is maybe 36db. I only know of one company with a TRUE shelf...a brick wall shelf like I said and thats the Lake Contour guys.. THe problem with a shelf though...your cabin gain isnt a freakin shelf...it is not a infinite db/octave gain at X freq. It is a slope. Quite pissing and moaning at me about what is and isn't go out to your damn car and put it together..then listen...just listen to your system...a SHELF filter will not help...you need to quit trying to get rid of problems before your system is ever done...and learn how to use what you have. At the most all you need is a GOOD and TRUE parametrik EQ. One that you can sweep the Freq, adjust the gain, and adjust your Q. Cabin gain again is not a infinite/db per octave phenomenon. Contrary to your 31band RTA or your ears and test tones or whatever you are using to test tells you...Unless of course you are using SMAART or god forbid you got your hands on a Meyer SIM or even worse TEF machine...And please before you come at me with you don't even know what shelf is, please go back and reread our previous discussions...I do sound for a living for the billionth time. I was also trying to help in the above...and again I say...shelf filter is not what you need...at all...get off the PC and go actually fiddle and play with a finished install...its amazing what you can get with non sofisticated gear and good ears and the most important...A GOOD FUNDAMENTAL INSTALL!!!!
 

·
Registered
Joined
·
1,397 Posts
and a shelf filter would be an ideal tool in this case.
Please, tspence, teach us more!

I still don't understand why you waste your time asking questions, when you already know everything. Drop the pretense and please just enlighten us.

Shelf filters, rear 6x9 enclosures to protect from VBA, sensitivity matched midbass and mids, I am learning so much. Please continue.
 

·
Registered
Joined
·
17,149 Posts
I feel it's a very legitimate question and he's touching on something that I swear by. I build car enclosures to go low, I DON'T build the enclosure around the car's natural boost. I would rather REDUCE the power to the sub enclosure to compensate for natural gain than throw power at an in-efficient enclosure that is still huffing along. Andy and others have touched on this several times also and it's a thing in car audio that will never be agreed upon. I use the amplifier's subsonic filter and one filter in the alpine to build a shelving filter to compensate for the car. This gives a great amount of headroom int he lower octaves due to the fact that you are essentially reducing gain the lower you go. I firmly believe this is why I have gotten by with relatively low amounts off power on my sub channels for so long. My way of doing it is simply barbaric, and I do it by ear, But I swear it works.

Chad
 

·
Registered
Joined
·
675 Posts
I couldn't agree more chad...but of course you are much more eloquent. I never use EQ's to boost anything nor design cabinets to compensate for cabin gain. Acknowledge its there, then use subsonic filters to roll off the drivers naturally. And I set everything by ear always and by golly it works great. Boosting EQ just kills headroom..but the point of my presentation is Shelf filters are not natural to what is going on in the car...and the last thing you'd use the filter/xover/ etc for is boosting...
 

·
Registered
Joined
·
17,149 Posts
I couldn't agree more chad...but of course you are much more eloquent. I never use EQ's to boost anything nor design cabinets to compensate for cabin gain. Acknowledge its there, then use subsonic filters to roll off the drivers naturally. And I set everything by ear always and by golly it works great. Boosting EQ just kills headroom..but the point of my presentation is Shelf filters are not natural to what is going on in the car...and the last thing you'd use the filter/xover/ etc for is boosting...
Shelving filters are in fact very close to what is going on in a car if you want to compensate for cabin gain, you need to find out the slope and -3 and have at it, it won't be perfect but it will be damn close. just like the OPPOSITE of the Bag-Eng rigs we were talking about earlier ;)
 

·
Registered
Joined
·
675 Posts
But its not a infinite db/ocatve slope is it? I can see steep, maybe 48db/oc but brick wall steep? I'm thinking it could be taken care of with "shelf" filters like in a meyer Galileo processor but thats not even a infinite slop, but those are perfect for this. Its just real steep not a real shelf filter. I'm giving you the ol stink eye, haha. Thats why I like me parametrik EQ's, sweep it to the cabin gain freq, adjust your Q accordingly and pull it out some...but with galileo or similar (lake contour, etc) you can just see it on a screen and so forth...I'm just not convinced its a brick wall shelf but a steep filter....am I wrong here?? :D Hey i reserve the right to be wrong, I love to learn
 
1 - 20 of 75 Posts
Top