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Discussion Starter #1 (Edited)
This is my first venture with component drivers and I was looking forward to improving my imaging compared to my old coaxial setup but I can't seem to convince myself that I did not actually diminish my soundstage instead of improved it from my old setup.

As a bit of a intro, I'm a college kid on a peanuts budget. I'm just trying to have fun tinkering with the stereo in a car that I spend MANY HOURS IN. I drive 600+ miles a week during the school year and really enjoy being able to take pride in how my car sounds.

My setup at the moment consists of tweets in the pillars, mids in the doors, and midbass in the rear passengers foot space. Can I make a convincing image with this sort of setup without time-alignment and other heavy processing? I have a set of heavy 4" Audax drivers that I could use as a dedicated midrange (and have a 2-way midbass setup instead), but these are going to be difficult to install in my car (I can't have kickpanels). I was wondering though that if maybe I used the 4" drivers that I could blend the mids and tweets more easily, but I really don't know - any help would be appreciated.
 

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Discussion Starter #4
I don't want to sound smart but I could figure that out myself, that's why processors with it cost three, four, five, hundred dollars etcetera...

What I'm asking is can I make this stage work without T/A. Should I resort to a point-source mid/tweet combo and only front-firing midbass? Can these aspects blend without the aid of T/A?
 

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midbass in the rear and not in the front might mess up your soundstage anyways. rear if used at all is ideally for fill and nothing else, and you're basically putting better sound in the back than in the front. also midbass is easier to localize than sub bass, so I can imagine it just sounding a little strange. what are you going to do to add time alignment if you decide to go for it?

time alignment will make the soundstage wider, that is to say, your speakers will seem much farther apart. see if you can find an alpine dealer with a 117 in stock. they have built in t/a and it's really nice on the demo.

as for your "can't have kickpanels", there's always options. q-logic sells them prefab, and for a lot of them they actually recommend you bend the e-brake out of the way. also you could get an electronic e-brake kit, so the e-brake will engage/disengage at the push of a button like an audi.

always options, get creative!

to answer your question though, no time alignment is a luxury, and you don't REALLY need it. Even a lot of people I know who have it don't seem to play with it at all.
 

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you can get good staging without T/A. Try to get the path length the same distance for your tweets and mids. I wonder about your mid-bass in the rear area.. where is it crossed over at? I bet those are messing up your image a bit.

I had a two-way running off passive xovers that had pretty good stageing... not as good as if I had active crossover with TA but still pretty good. On a tight budget you should really concentrate on the install as there is little you can do about the equipment.


I would like to point out that you can get a Kenwood x4r (what I have) that has built in T/A for under $200. It will give you 90rms x4 with TA and a cross over. It is really good for a two way system.

Others on this board will tell you that you MUST go three way but I don't buy it... if you are on a tight budget. I have heard some great sounding two way systems.
 

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Discussion Starter #7
From what I've read I thought I may be able to get away with "rear" midbass in this case. My 8's only play from 150Hz and lower and are right behind the front seats, this location is VERY different from the rear deck as it is barely behind you.

If I go with a fancy HU with it I would imagine I would have to get a new EQ as my old, cheap RF OEQ2 only deals with 1 pair of inputs and outputs. I would imagine that T/A on a single fullrange source would be a disaster!

I kind of thought that T/A wasn't absolutely necessary but my distance from my mids to the tweets is very large and my midbass are in a different location yet - I thought T/A may be the only way to bring it all together...

Thanks for the encouraging words though... I will keep thinking.
 

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Discussion Starter #8
If I went with the Kenwood amp my A/D/S/ P640 wouldn't be happy... It cost me a pretty penny too. Even though a "high-tech" amp like the one you mentioned may be beneficial for my midbass, right? I only have about 75 watts per driver going to my 8's right now, but they are also 8-ohm drivers - so I think I could make it work.

Does the amp have separate T/A for each side? I thought that was most beneficial. Is the amp's system just a common delay?

How would I equalize pathlengths with both my mids and tweets when one may be on the floor and one may be on the pillars? I hate to think of trying to get kicks in the car as leg space is already difficult - I'm 6'3" and have a size 13 shoe!

But anyway though I appreciate the ideas guys. Any other amps that have this feature onboard for a reasonable price?
 

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that Kenwood x4r is really meant for a two way system. The crossovers are made so that you can do tweeets on two channels and mids/mid-bass on the other two channels. Yes you can do 4 way time alignment/delay.

to set it up you measure the distance from a common point (usually the drivers head position) to each of the different speakers. Then you figure out the delay in milleseconds you need to dealy each speaker.
 

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midbass in the rear and not in the front might mess up your soundstage anyways. rear if used at all is ideally for fill and nothing else, and you're basically putting better sound in the back than in the front. also midbass is easier to localize than sub bass, so I can imagine it just sounding a little strange. what are you going to do to add time alignment if you decide to go for it?
Couldn't disagree more. :D

Midbass is definitely do-able in the rear. I've seen many many cars and rooms do this. Done it myself many times too. My HT setup is governed by similar principles, and the image is unbelievable (2 ch!). The key is 1) where is the lowpass? 2) what other potential cues are there? The lack of time alignment might make life difficult, but I still think it can be done.

as for your "can't have kickpanels", there's always options. q-logic sells them prefab, and for a lot of them they actually recommend you bend the e-brake out of the way. also you could get an electronic e-brake kit, so the e-brake will engage/disengage at the push of a button like an audi.
Not everyone wants them! I'd HATE kick panels in my car. I have enough leg room problems. The only time I've really been able to use kickpanels was in an old Deville I had with bench seats. :)

to answer your question though, no time alignment is a luxury, and you don't REALLY need it. Even a lot of people I know who have it don't seem to play with it at all.
I mostly agree with this. I think most installs can get good sound without it.

We spend a lot of time trying to achieve that extra 1%. Most regular folks would be more than happy with most of our audio systems, but we're the lunatics who strive for perfection and spend a ridiculous amount of time and money trying to get there. I think time alignment can be very important for us 1 percenters. There's no question that it achieves very perceptible results. But so what? :)

I was talking to a friend the other day and he thought I was INSANE for upgrading my sub. He just couldn't understand it. He's not a 1 percenter.

It ultimately comes down to the individual's goals. Maybe a well-defined center image gives one guy a boner, and the other guy couldn't care less. That's why these sorts of questions are useless... "how important is time alignment?", "should I upgrade my XYZ?". Nobody can answer that except for the USER!
 

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From what I've read I thought I may be able to get away with "rear" midbass in this case. My 8's only play from 150Hz and lower and are right behind the front seats, this location is VERY different from the rear deck as it is barely behind you.
Yes, you were right the first time. :)

150Hz is VERY LOW. Most people don't even realize that the subwoofers sitting in the corner of their living rooms are probably playing that high, at least. I think PL2's spec is 150Hz, actually. Nobody's talking about their HT image being all screwed up by that. And if it is, it's because their crappy Ikea furniture is rattling all to hell :D

My 15" subwoofer in the backseat is lowpassed at 200Hz and I have a rock-solid center image. There's no reason why 150Hz content would pull back your image, UNLESS you fail to deaden properly and you get high frequency rattles coming from the back.

I kind of thought that T/A wasn't absolutely necessary but my distance from my mids to the tweets is very large and my midbass are in a different location yet - I thought T/A may be the only way to bring it all together...
Here's something that no one's gonna admit, but it's absolutely true...

Your tweeters don't need time alignment.

Why? Because their wavelengths are so damned short. Adjust your tweeters 1ms with respect to the mids and you're shifting the phase several periods! The ear simply does not use this information to perform localization at high frequencies. Time alignment can alter tweeter/mid interaction only inasmuch as it alters the phase relationship. You can do practically the same thing by playing with polarity. Actually, many manufacturers do this in their passive crossovers. I think it was Polk (?) that used to offer a distance switch that simply reversed polarity when the distance between mid and tweet was large. :)
 

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Discussion Starter #13
Thanks very much to everyone for your input...

I realize how subjective this kind of thing is. I was trying to get at something but maybe I wasn't clear enough, what I am asking is that I happen to think my imaging has suffered from my recent changes and I'm asking how much T/A may be able to help...

I used to have a bandpassed, mixed-mono 3.5" center channel driver on the dash right beneath the windshield and it seems I miss this single speaker a awful lot - I removed it when I went to separate tweets/mids. With the center channel my mids were still in my doors, but it seems as if the imaging was just better.

The midrange seems to have suffered most but I have yet to make any measurements and do any fine-tuning since I'm not sure If I'm even to a point where I would consider leaving it for any time. The only mids I have playing now are the 5.25" paper drivers playing in the doors and it seem as if I've lost a lot of amplitude and my center image is just more diffuse - it's strange it doesn't seem skewed left or right it just seems as if there is lacking midrange material high in the soundstage. The tweeters seem to be playing by themselves, maybe it's because they are on on-axis (or near it) and the mids are very off-axis in the doors.

I think my midbass can work even without T/A. After reading some of Patrick's comments about leaky doors making strong low midbass nearly impossible I figured that these enclosures behind my seats would be best as they are really sealed. I thought that keeping them low would keep them from skewing the stage. That being said I might try running them up to 200Hz, my doors aren't sealed well at all and I don't have $200-$300 to spend in deadening/sealing them so running my door speakers at a low frequency is probably a bad idea.

I will still be considering what I will do with my mids but I will try all possible combinations of polarity and see if that helps. I think that may be one of the best things I can do for my setup while not costing me anything.

Speaking of creativity anyone have any ideas how I can use my 4" drivers? How terrible would it be having mids near the firewall? They are pretty hefty for the dash.

Thanks again to everyone.
 

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We spend a lot of time trying to achieve that extra 1%. Most regular folks would be more than happy with most of our audio systems, but we're the lunatics who strive for perfection and spend a ridiculous amount of time and money trying to get there. I think time alignment can be very important for us 1 percenters. There's no question that it achieves very perceptible results. But so what? :)

I was talking to a friend the other day and he thought I was INSANE for upgrading my sub. He just couldn't understand it. He's not a 1 percenter.


how true, how true. one of my best friends loves the way my cars sound but always rips on me for changing equipment. i was telling him about the latest set of 8s i got for one car and he stopped me mid-sentence quite abruptly. "i don't care who makes them, how much power they can take or what they sound like. your car sounded great for the last few years no matter what was in it, and even i if i had a clue what those specs you spout off meant it wouldn't matter because you would be changing them next week!"

all i could do was laugh...
 

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Discussion Starter #15
Bump...

I've noticed that my image centers MUCH better when you move your head forward near the windshield. The image seems to be most focused where the tweets and mids are in a straight vertical line from each other, I may've read about this phenomenon before in sound but it's somewhat fuzzy. Anyone fill me in?

Thanks,
Travis
 

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Discussion Starter #17
It was probably a psychoacoustics deal...

Countless people told me that I shouldn't have it. It was a "dumb" center driver in that it didn't have any fancy image-altering processing, just mixed L+R, bandpassed, and attenuated. Professionals and SQ competitors said when I asked that I could make a strong center image without it and that it would only "cloud" my image since it was smaller than my midrange drivers.

This was when I was using all coaxials in the car, and when I got rid of the coaxial door drivers I got rid of the coaxial center driver (even though really the tweet in the center didn't contribute much if at all). It may have also had something to do with the crudely-fabricated enclosure I made for the driver, since I didn't want to cut into the dash it was on top of the dash in not-so-attractive small box, but that didn't mean that it didn't sound alright.

Anyway, it's gone now. It was a experiment to attempt to improve my sound quality and imaging but it has somewhat backfired. Do you really think that I should use it again? I would like to see if my 4" midrange drivers would improve things...

What about a firewall location for mids? I know it sounds crazy but can midrange frequencies work well when they're that obstructed?

Thanks,
Travis
 

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It was probably a psychoacoustics deal...

Countless people told me that I shouldn't have it. It was a "dumb" center driver in that it didn't have any fancy image-altering processing, just mixed L+R, bandpassed, and attenuated. Professionals and SQ competitors said when I asked that I could make a strong center image without it and that it would only "cloud" my image since it was smaller than my midrange drivers.
They were evidently wrong. ;)

This was when I was using all coaxials in the car, and when I got rid of the coaxial door drivers I got rid of the coaxial center driver (even though really the tweet in the center didn't contribute much if at all). It may have also had something to do with the crudely-fabricated enclosure I made for the driver, since I didn't want to cut into the dash it was on top of the dash in not-so-attractive small box, but that didn't mean that it didn't sound alright.

Anyway, it's gone now. It was a experiment to attempt to improve my sound quality and imaging but it has somewhat backfired. Do you really think that I should use it again? I would like to see if my 4" midrange drivers would improve things...
If it sounded better with it, then I don't understand why you're not using it.

What about a firewall location for mids? I know it sounds crazy but can midrange frequencies work well when they're that obstructed?
Yep. Of course, I've seen the word "midrange" include everything between about 60Hz and 6kHz, so the question is sort of vague. :p We need to stop using words like "midrange", "midbass", "highs", and all the rest, because they don't actually mean anything. What bandwidth are you talking about, specifically?
 

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Discussion Starter #19
I don't want to run my tweeters any lower than 4kHz, so that is the upper limit, but the lower limit is really yet to be determined. It could be anywhere from 300-1000 Hz, depending on where I lowpass my 5.25" drivers.
 
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