8" midbass dilemma

[edouble101 314]

i think the problem on the bottem end is enclosure related.

the shit at 300hz might be car acoustics.

Why the peak at 100hz and the rapid fall-off on either side of it??? I just don't understand that.

I could be wrong, but it might be from the mounting location being in the kick area. *Cabin characteristics at play*

I haven't modeled your drivers, but the small enclosure volume might throw that peak in.

How thick are your enclosures? Are they deadened inside with any clay, or just fiberglass? Reason I ask, is resonance.

The enclosure thickness varies. I am using a 3/4" baffles that was fiberglass then smoothed out with kitty hair that is very thick (about an inch) near the mounting ring. The inside of the enclosure is bare metal and expanding foam. I stuffed the enclosure with poly fill, leaving a clear path to the AP Mat, and that did nothing to the FR.

[edouble101 314]

i think the problem on the bottem end is enclosure related.

the shit at 300hz might be car acoustics.

Why the peak at 100hz and the rapid fall-off on either side of it??? I just don't understand that.

i'm not really sure because you have filters on and i cant tell what is a peak.

disable the lpf @ 400hz so we can see establish if the peak at 100hz is a peak. It could be that its fine at 100 and down at 300 and down <100.

I will try and take more measurements this afternoon/evening.

[///M5 2,833]

The RTA is screwing you up more than helping.

I am very dubious on your excitation and how it is lined up with the "1/3" octave analyzer you are using. I used quotes because of course TrueRTA doesn't really do 3rd octaves but synthesizes them from an FFT and depending on how you set that up it can seriously chop your signal. Displaying 1/3 octaves in a chart like that makes no sense either. Nor does using a single average in particular at the headrest. Either way based on your settings and your crossover the response is expected. It's a little confused, but of course since you aren't doing this in the near field where you could truly see your response that is expected.

I could go on and on, but it's currently giving you absolutely no information and obviously has you seriously confused. What it shows you has nothing to do with your lack of midbass either. Also can't say I understand why you just hopped up and bought that JL either. Randomly picking enclosure size and drivers isn't going to net even reasonable results.

[edouble101 314]

The RTA is screwing you up more than helping.

I am very dubious on your excitation and how it is lined up with the "1/3" octave analyzer you are using. I used quotes because of course TrueRTA doesn't really do 3rd octaves but synthesizes them from an FFT and depending on how you set that up it can seriously chop your signal. Displaying 1/3 octaves in a chart like that makes no sense either. Nor does using a single average in particular at the headrest. Either way based on your settings and your crossover the response is expected. It's a little confused, but of course since you aren't doing this in the near field where you could truly see your response that is expected.

I could go on and on, but it's currently giving you absolutely no information and obviously has you seriously confused. What it shows you has nothing to do with your lack of midbass either. Also can't say I understand why you just hopped up and bought that JL either. Randomly picking enclosure size and drivers isn't going to net even reasonable results.

My use of the RTA software is new to me. Adjustements, calibration and setup are things I am learning as I go. What I hear and the RTA measurments I am taking agree with each other. That makes the RTA software useful enough to me. I am enjoying making installation adjustments and being able to physically see the results.

I bought the JL based on the installation parameters I currently have and what my goals are. There are many errors in my design and installation and at this point I am trying to achieve my goal without ripping out my kick panels completely. I know it isn't the way you would do it. There is a lot of trial and error needed. Maybe more for me than others

I do appreciate any helpful assistance. From my mistakes and learning from them, hopefully somebody reading this thread will find it helpful in designing and building their car audio dream.

[///M5 2,833]

Start by displaying your 1/3 octaves AS third octaves and not narrow bands. If you can't in that software, I'd stop measuring. Use random excitation and do at least 100 averages. Measure in the near field first. I know you want to know what your ears will hear, but you need to focus on what the enclosure will do. Make sure to use complex averaging as phase is important. Shut everything off but a single driver for measurement. I'd also first shut off ALL processing. I'd recommend some reading on 1/3 octaves as well. Currently you are measuring at ONLY 4 points below your crossover frequency and displaying way more than 4. That makes ZERO sense. Obviously the 5th being up at 500Hz is rolling off based on your crossover and since that is only the center point it's squishing your response.

Either way, for this driver a measurement system does you pretty much no good. You have an output problem with a driver that is in a far from optimal enclosure and it's too be expected.

Your mids/tweet plans are going to be just as ugly. I'd seriously rethink them.

[edouble101 314]

Start by displaying your 1/3 octaves AS third octaves and not narrow bands. If you can't in that software, I'd stop measuring. Use random excitation and do at least 100 averages. Measure in the near field first. I know you want to know what your ears will hear, but you need to focus on what the enclosure will do. Make sure to use complex averaging as phase is important. Shut everything off but a single driver for measurement. I'd also first shut off ALL processing. I'd recommend some reading on 1/3 octaves as well. Currently you are measuring at ONLY 4 points below your crossover frequency and displaying way more than 4. That makes ZERO sense. Obviously the 5th being up at 500Hz is rolling off based on your crossover and since that is only the center point it's squishing your response.

Either way, for this driver a measurement system does you pretty much no good. You have an output problem with a driver that is in a far from optimal enclosure and it's too be expected.

Your mids/tweet plans are going to be just as ugly. I'd seriously rethink them.

It is going to take some time for me to fully process this. Thank you for helping.

Where should I position the mic for near field measuring?

I would like to stop tuning with the RS225's and drop in the ZR800-CW's and start over with tuning. Do you agree?

What is "complex averaging as phase"?

[ssh 924]

I believe nearfield would be 6" - 12" ish in front of the cone.

Edit: I've seen people do closer, so really I don't know. I've seen some people in the HT crowd doing 12" (not saying they are correct), but also ran into this: http://www.claudionegro.com/sw/swacoustic/nearfield/nearfield.html

So yeah I don't know wtf I'm talking about.

Perhaps the cook book would shed some light.

Edited July 2, 2012 by stefanhinote

[///M5 2,833]

Take 3 steps back. Why are you measuring? What are you trying to accomplish? The wrong goals lead to the wrong techniques which lead to the wrong conclusions (you've been there already). Perhaps my initial comment of "the RTA is screwing you up more than helping" could be expounded to say I flat out see no benefit in you measuring anything. Of course, I am assuming your goals although they are pretty transparent IMO. That being said, state them and maybe I made a poor assumption.

[edouble101 314]

Take 3 steps back. Why are you measuring? What are you trying to accomplish? The wrong goals lead to the wrong techniques which lead to the wrong conclusions (you've been there already). Perhaps my initial comment of "the RTA is screwing you up more than helping" could be expounded to say I flat out see no benefit in you measuring anything. Of course, I am assuming your goals although they are pretty transparent IMO. That being said, state them and maybe I made a poor assumption.

My goal for this install is to achieve a realistic soundstage. I want to hear the soundstage in front of the vehicle at eye level. I do not want to call this a flat out SQ install. I do enjoy an exaggerated sub stage and midbass. I want my midrange and high end to be smooth and not painful to listen to at high volume. It is very important to me to have no audible distortion caused by driver fatigue due to not being able to handle the power from my KS900.6

I mostly listen to female vocalists such as Cranberries, Dido, Jem, Flyleaf... I also listen to a lot of heavy metal genre and rap (to satisfy the basshead in me).

I am fed up with my soundstage in the middle of my dash. I am also fed up with having a lack of midbass. When I put on my headphones and play Metallica I imagine my car sounding that good.

My terminology when it comes to describing sound is horrible.

[edouble101 314]

Why I am using an RTA is to help me achieve the sound I am looking for. Plus the geek in me enjoys it.

[///M5 2,833]

My goal for this install is to achieve a realistic soundstage. I want to hear the soundstage in front of the vehicle at eye level.

Measuring won't do anything for that.

I do enjoy an exaggerated sub stage and midbass.

Then the 225 is a terrible choice and the JL isn't all that much better. Don't read a name and believe you know what that means a driver will do.

I want my midrange and high end to be smooth and not painful to listen to at high volume. It is very important to me to have no audible distortion caused by driver fatigue due to not being able to handle the power from my KS900.6

Fatigue not being able to handle power is stupid concern. If you were concerned with output that's another story. Smooth isn't descriptive either...I'll read it as you don't want it to sound like shit.

I mostly listen to female vocalists such as Cranberries, Dido, Jem, Flyleaf... I also listen to a lot of heavy metal genre and rap (to satisfy the basshead in me).

For the vocalists I'd focus on a nearly single speaker install. Point source is your friend. You can help the midbass with a driver and the sparkle with a tweet, but the focus HAS to be on the mid. Metal of course you'll have different goals and rap also. Start deciding where you want to compromise as you are going to have to. The female vocalists will be the easiest setup to stage, rap who cares as the stage is absurd and metal you are going to run into a dynamics problem if you focus on staging.

I am fed up with my soundstage in the middle of my dash.

Why are you fed up with it? What about it is frustrating?

I am also fed up with having a lack of midbass.

Not solving that with the JL. Also I'm not sure what YOU mean by midbass. Some examples will help. Of course the easiest way to get midbass is with your subs, but it pulls the stage. Imagine that another compromise in car audio.

When I put on my headphones and play Metallica I imagine my car sounding that good.

Hope you have a good $50,000 to try and get it to sound that good. Or in other words, good fucking luck it ain't gonna happen, not even fucking close. Seriously like shit in comparison.

My terminology when it comes to describing sound is horrible.

That and your comprehension has been exposed. I guess this explains why you keep thinking the Xcon is a Q. Pretty much no clue at all. Perhaps you should slow down a bit and try to understand something before buying or typing. It would help. If you can't state your goals and needs well you won't find a solution for them. Just not possible. When your goals are based on a pretext it's even worse. Share reality, think about it, plan it and then and not before then execute.

[edouble101 314]

That and your comprehension has been exposed. I guess this explains why you keep thinking the Xcon is a Q. Pretty much no clue at all. Perhaps you should slow down a bit and try to understand something before buying or typing. It would help. If you can't state your goals and needs well you won't find a solution for them. Just not possible. When your goals are based on a pretext it's even worse. Share reality, think about it, plan it and then and not before then execute.

I am not here to get into a pissing contest with you. Everything I stated was easy to understand. Enough with the bullshit questions about topics I already answered. You post in this thread to fuck with me, I get it.

I made a bad decision on driver selction and an even worse decision on enclsoure size. Yeah I fucked it up - no shit.

I am learning as I go which is one of the reasons I started this thread. You have me chasing my tail which is ending up no where. Goal accomplished on your end.

And yes I have mentioned in numerous thread numerous times what I thought of about SSA products. My ignorance has been pointed out to me and cleared up numerous times as well. I get it. Get the fuck over it.

Edited July 2, 2012 by edouble101

[Notorious97200 339]

edub : take it easy, man !

Simply follow what M5 is telling you. He knows his sh...!

You bought some expensive drivers (the JL) ! I hope you will be happy with them.

I bought some Aura midbass driver (using nedymium motor) for a friend's install : they were sooo cheap (like $20 each !!!) on madisound or parts-express (I don't remember). So cheap, I bought 4 speakers instead of 2, and my friend is still very very happy with them. He's looking for a way to use all 4 in his car.

But we don't use no RTA, or anything. Only our ears. The results are not so bad for now !!!

Good luck

[edouble101 314]

edub : take it easy, man !

Simply follow what M5 is telling you. He knows his sh...!

You bought some expensive drivers (the JL) ! I hope you will be happy with them.

I bought some Aura midbass driver (using nedymium motor) for a friend's install : they were sooo cheap (like $20 each !!!) on madisound or parts-express (I don't remember). So cheap, I bought 4 speakers instead of 2, and my friend is still very very happy with them. He's looking for a way to use all 4 in his car.

But we don't use no RTA, or anything. Only our ears. The results are not so bad for now !!!

Good luck

I thought PE had them for $9.88 You prolly paid more for shipping!

I think the JL's will be the best driver for my installation and goals. I spent a lot of time reviewing the 8" selection from many sources. The ZR800 certainty wasnt choosen for the JL Audio logo.

[///M5 2,833]

I am not here to get into a pissing contest with you. Everything I stated was easy to understand. Enough with the bullshit questions about topics I already answered. You post in this thread to fuck with me, I get it.

I made a bad decision on driver selction and an even worse decision on enclsoure size. Yeah I fucked it up - no shit.

I am learning as I go which is one of the reasons I started this thread. You have me chasing my tail which is ending up no where. Goal accomplished on your end.

Get defensive much? Geez. Not my goal at all. There is a HUGE difference in "midbass" to a metal head and someone who listens to vocal music. HUGE. Nearly opposite in fact. After reading all your thread I sort of figured you may be confused at what you think you want in how you describe it or I read it. My goal was to answer your question, plain and simple. Stop reading into things. If I wanted to send you in circles that'd be easy and I wouldn't have typed so much.

And yes I have mentioned in numerous thread numerous times what I thought of about SSA products. My ignorance has been pointed out to me and cleared up numerous times as well. I get it. Get the fuck over it.

Glad it finally sunk in although it couldn't have been much before a few days ago. I brought it up here not to make it clear, although it's good to see you finally woke up, but to show you exactly how your assumptions are hurting you in the process you are pursuing and to step back and more clearly describe (even if it's just to yourself) what you really want.

[///M5 2,833]

I think the JL's will be the best driver for my installation and goals. I spent a lot of time reviewing the 8" selection from many sources. The ZR800 certainty wasnt choosen for the JL Audio logo.

Perhaps you should start by describing your goals then, from what I've read that isn't the conclusion I would have drawn. Not even close.