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Old 02-13-2014, 12:11 AM - Thread Starter
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Ok... for clarification please explain a 1st order 100hz low bypass and native frequency response. 6db by adding the 3 2242's to front or by placing the 3722's on sides/rear wall? Sorry for dumb questions....Just want to make sure im tracking properly.
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Old 02-13-2014, 05:10 PM - Thread Starter
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I included a couple links if anyone is interested regarding crossovers. Sometimes terms are thrown around and most of the time I can track along, but not being an audio expert as far as design (I know what I hear) I get a little confused or honestly at times I just simply have big brain farts! I do know what a 100hz first order low pass is but that country boy (no offense to country boys lol, I was raised in a big city and moved to modesto which was considered country back in the early 70's) in me needs simple terms sometimes like: cross it over at 100hz, or a 100hz filter, etc.. but when you add too many terms my brain kinda swells biggrin.gif Point being first order is the simplest of crossovers. Hey John, I appreciate you making things easy for me, sorry for not being able to connect the dots at times! smile.gif




http://www.the12volt.com/caraudio/cross6db.asp


http://www.tune-town.com/Cars/stuff/pac/pdf/crossover.pdf


Okay...back on track...... wink.gif
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Old 02-13-2014, 05:16 PM - Thread Starter
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Quote:
Originally Posted by LTD02 View Post

if they have the same native frequency response, whatever that may be, then they will combine +6db when level matched like this:

100hz first order low pass in effect.


This part I need clarification, same native FR?
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Old 02-13-2014, 05:27 PM
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native frequency response is simply what the speaker does with no equalization applied.

it could also be called the raw response or the un-equalized response.

we could take a look at the spec sheet and make a pretty good guess. i was just presenting the concept in the post above.

"for clarification please explain a 1st order 100hz low pass"

filters are measured in terms of "order" 1st order, 2nd order, etc. each order is 6db/oct.

so a 1st order 100hz low pass filter, starts to rolloff the sound very roughly around 100hz with a gentle slope of 6db per each octave (with each octave being a doubling of frequency). so the response slopes down 6db by 200hz in the example and is down 12db by 400hz, etc.

a gentle rolloff helps keep the phase response of the two systems pretty close. if they get out of phase, they will be cancelling each other instead of summing and summing is what you want.
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Old 02-13-2014, 05:28 PM
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"6db by adding the 3 2242's to front or by placing the 3722's on sides/rear wall?"

6db by adding the 2242 next to the 3722's.

I'm not sure what you are talking about when you say placing the 3722 on the sides/rear wall.

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Old 02-13-2014, 05:32 PM
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the native response of the 3722 from the spec sheet is this:



so if following this approach, we'd design a cab for the 2242 that has a similar rolloff in the bass.

-3db point is around 50hz.

as it turns out, my guess was almost dead on. :-)

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Old 02-13-2014, 05:32 PM - Thread Starter
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lol, you da man!!
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Old 02-13-2014, 05:35 PM
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here is the 2242 in a 4 cubic footer tuned to 40hz.

that's pretty close. +/- a little on tuning or size won't really matter. that's the ballpark.


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Old 02-13-2014, 05:36 PM - Thread Starter
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Okay so I will get 6bd by adding the 2242 in line with my 3722's...got it, that's what I though you meant but I kinda muddied it up with two topics. By placing lower section of the 3722 at rear wall facing screen, or at side walls facing seats, Im wondering what effect that would have? I see some guys with subs throughout their room so I wonder if there is a benefit to that. I have plenty of subs smile.gif
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Old 02-13-2014, 05:37 PM
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"Been thinking too what would happen if I put the LF section of the 3722 on side and back walls."

this would not work at all. the LF section of the 3722 is producing a good chunk of the midrange and that is very directional. you definitely want to keep those cabs behind your screen for the front three channels.

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Old 02-13-2014, 05:39 PM - Thread Starter
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okay, got it...Thanks!!
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Old 02-13-2014, 06:36 PM - Thread Starter
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Looking at a cabinet that will serve as a base for the 3722's for the 2242 I come up with

30" wide
30" high
18" in depth

9.375 cuft not considering thickness or bracing

This will keep the 2242's at the same height as the lower SI18's on the Bass Cannon's
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Old 02-13-2014, 06:58 PM
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The hight of the bass cannons in relation to the 3722's is not important, acoustically. As LTD02 has already explained, you can't move the woofer cabinets in your 3722 anywhere other than were they are intended, which is under the horn. Those 15" woofers produce a lot of the mid-range, and by moving them away from the horns, you will completely destroy the crossover blending between the high and low frequency drivers. Also, keep in mind that the woofers in the 3722's are not subwoofers, they are regular woofers.
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Old 02-13-2014, 07:16 PM
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Quote:
Originally Posted by 316 View Post

Looking at a cabinet that will serve as a base for the 3722's for the 2242 I come up with

30" wide
30" high
18" in depth

9.375 cuft not considering thickness or bracing

This will keep the 2242's at the same height as the lower SI18's on the Bass Cannon's

Port length even with 8" port will not be an issue either, even 2 of them would fit (almost).
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Old 02-13-2014, 07:17 PM
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316, LTD is dead-on... do whatever you can to keep all that midrange as together as you can/
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Old 02-13-2014, 07:19 PM - Thread Starter
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Marty, The 3722 will stay as one unit placed on stands that will be the 2242 cabinet. The lowest point of the 2242 has to be higher than my stage so they will not be firing into the bottom of my stage/screen. Either way the 3722 would have to be elevated to clear my stage. I designed it so the bass cannons clear the stage and since they are too large to be placed on the stage they have to clear it. All the faces of my drivers will be even so I will end up with a few inches between 3722 and rear wall if i placed bass cannons against the wall.

What prompted my question about placing horn section on top of 2242 cab and moving LF section to rear wall was becauze of my future concern if i changed my horn section i might not have enough height. I failed to consider the range of the 3722 LF section.
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Old 02-13-2014, 07:31 PM - Thread Starter
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Quote:
Originally Posted by urapnes1 View Post

316, LTD is dead-on... do whatever you can to keep all that midrange as together as you can/

Will do. I still want to keep ports from 2242 cabs firing away from screen. There is more air moving from ports than the sound waves from cones and do not want ports moving my screen. When I crank it up I can feel air from 3722 which might be okay but dont want to add any more from 2242.
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Old 02-13-2014, 10:21 PM
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9cf same tune, fwiw


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Old 02-14-2014, 11:08 AM - Thread Starter
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This is how the layout will look.

Okay guys, now before I share this with you all you have to understand something, I don't have to tell you this but...I try to be a humble guy and in no way do I think I am perfect or that I know everything. Its easy to pretend because all I have to do is search the internet and present myself as a know-it-all...but I'm not. I'm learning and I appreciate so much what I learn from all the guys here on the forums.

Now the ears hear, the charts predict, and the test gear measures. The ultimate test is the ears. No matter what the graphs say it comes down to the ears, they have the final say in my humble opinion. So, LTD02 and other members like cocostan, urapnes1, and a few others have either stated or shown charts that predict what my system should be sounding like...but to me those charts were not accurate. I have also stated how I think there is something wrong with my system and It would sound good but then after listening for a while the ears and brain tell me hey dude, something is not right, and its not. Well I could go on but you get the point...no matter what adjustment I made everything sounded better at first but the brain would reset and tell me no. Trust your brain...and your ears!!!!

I am going to show two pictures and you tell me what you see different:





Well gentlemen, (and ladies?) I got my MOJO BACK!!
I am listening to two speakers with no subs, yes the bass cannons are turned off and this system kicks some serious BUTT!!!! That's four 15" drivers and two horns (waveguides if you like the updated fancier terminology)

So, did you figure out what the difference is?? Okay guys its okay to laugh but just don't call me names because everybody, if they are honest, has nuclear brainfarts of biblical proportions!!! biggrin.gif

I went over many PDF drawings over and over and with different horn sections until I finally figured it out. What jogged the ole brain was the location of the LF section and Marty and LTD02 made some comments that made a high voltage sound go off in my brain...I thought I was short circuiting and was looking all around for sparks.... Never felt that before, thought it was yet another sign of old age!!

So what do you see?? Cmon...someone answer cuz I'm not gonna say it!!! biggrin.gif

I'm surprised nobody caught it in earlier posts which makes me think...is anyone listening to me?? You know that's another sign of old age...talking to yourself! biggrin.gifwink.gif
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Old 02-14-2014, 11:17 AM - Thread Starter
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BTW, absolutely no regrets getting my 2242's cuz all I'm gonna have is MO MOJO!!

Run, don't walk and buy a set of 3722's !! For the price how can it get any better!! Seriously how can it???

Emotiva I owe you an apology, the UMC-200 rocks!! My stage is da bomb, I cannot express how thrilled I am with just two speakers playing my jazz, pop, rock, still going through my stuff and nothing sounds bad...its all good!! Oh midbass, pfft, I got snap baby!! And its going to get better! WHAT are you crazy!!!! Uh, I guess I am but so what, I gots big daddy snap, lol. Gonna make you want to tuck, drop, and roll, lol!! biggrin.gif Can you tell I'm a little happy? This is what I expected out of the JBL's...don't get me wrong, they still rocked but now its like I upgraded to a whole new system...unbelievable!!!
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Old 02-14-2014, 11:22 AM - Thread Starter
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Can't wait to put this system together.... smile.gif 2242's look bored.

If anyone is local and interested in a pair of EV's as shown in my pictures PM me $$ or trade. They sound good but I don't have room for them

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Old 02-14-2014, 11:29 AM - Thread Starter
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Quote:
Originally Posted by 316 View Post

Knowing JBL they may already have this figured out for me. I will have to verify and if it is what I think it is my cure will be pretty simple and straight forward. If you look at the crossover, it appears to have an output for another horn. I just have to find out if this is a pass through or if it is active and tie my horn into it and done. Assuming I decide to go JBL horn/tweeter smile.gif



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Old 02-14-2014, 11:31 AM - Thread Starter
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Quote:
Originally Posted by Martycool007 View Post

I would recommend adding a JBL-2404H as a super type tweeter,or perhaps you might be able to find some Be diaphragms for your current mids/high frequency drivers on those 3722's without adding a super tweeter, as the Be diaphragms will make the mids & highs have more detail, clarity, and sound smoother as well.

Even if you do end up adding a super tweeter, such as the 2404H or 2402 ect...how would you integrate it within the crossover and how can you make it blend and play well enough with the existing drivers?

Subwoofer discussion is getting boring! Seems like that's all that has been going on lately! So let's talk more about actual speaker building! LoL!

From day one something was wrong and I knew it.
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Old 02-14-2014, 11:44 AM - Thread Starter
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Quote:
Originally Posted by LTD02 View Post

another thing to consider:

http://www.avsforum.com/t/1489541/large-ported-dayton-ho18s/450#post_23827527

"the 2 [si 18's ported] I have in my room are simply destructive beyond belief in the midbass..." -worm

you will have 8.

your mains are 101db or so sensitive and you will have 6.

i'm just not sure, if, in your case, it makes sense to try to integrate another woofer in between them.


LTD02, at this point I have the 2242's so I will use them but you knew in your mind how those should have sounded and you were correct smile.gif four sound fantastic, six plus three 2242's, out of this world! But I'm cool with that! biggrin.gif
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Old 02-14-2014, 04:24 PM
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I don't know what the box is under your horn, but it appears to missing a power cord... wink.gif

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Old 02-14-2014, 04:28 PM - Thread Starter
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Mhutchins, nope...no power cord missing tongue.gif
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Old 02-14-2014, 05:53 PM
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Quote:
Originally Posted by 316 View Post

Mhutchins, nope...no power cord missing tongue.gif

Well, it kind of looks like you forgot to hook up the speaker wire to the dual 15" box. But it certainly couldn't have been that, right? tongue.gif
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Old 02-14-2014, 06:23 PM - Thread Starter
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Aaron, hah, nope, lol speaker wire was hooked up to LF section smile.gif
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Old 02-14-2014, 06:32 PM - Thread Starter
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Connected all speakers and amps today....Music sounds better in two channel with just bass cannons and R,L 3722's just the way it should... I'm exhausted from excitement, it just sounds so good and I seriously cannot believe its still going to sound better with 2242's and sound treatments once the room is done. Outstanding!! biggrin.gif
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Old 02-14-2014, 06:36 PM - Thread Starter
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Nobody can see where I went wrong yet until today? Is it so obvious that its not obvious? Cmon guys...somebody has to see it lol tongue.gif Hey if I'm not embarrassed to post my mistake nobody should be embarrassed to guess wrong biggrin.gif

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