Shoot off your ideas on good equipment...

exalted512

how about searching for a car like yours on cardomain?
you can give us some links to know what exactly were working with and you might find some good ideas
if you can wait til august ill be about an hour away from the houston area, gas and a meal and id be happy to help ya out
but thats a long time...
-Cody

LittleCar_w/12s

Well, when I go out today, I will try to get pics of the interior up front. I will pop off the cover and show the T-4 mounting hole too, though there is little that fits in there.

How many of you really do not use rear speakers?
Also, what would it sound like for passengers in the back seat if I had none?

Also if anyone has pics of a good front-stage install in a small car, feel free to post here.

LittleCar_w/12s

Ok I have pictures... they are huge though... do yall have highspeed or dialup?

if h/s i'll just post them , dialup, I'll edit to make smaller...

I am having trouble with my web-server randomly shutting down the IIS, so I will try to keep it running for you to see the pics, if not, just try again later.

Web address will be: http://village.ivybrook.com/mobileaudio/

If anyone here knows how to fix the random shutdown of IIS on a win2000 server, please let me know... I can't keep it on

Pics will be up soon....

neomagus00

i personally don't use rear speakers, and it's never seemed to bother passengers before (granted, we're usually talking etc. on the occasions when i have backseat passengers, but whatever).

i like my soundstage and most of my imaging; i can put pics up of where the speakers are if you want. and i drive a pretty small car.

LittleCar_w/12s

That'd be nice... I am at a loss as to where I can mount fronts without them being too bulky or in the way. My doors will not take a large speaker, simply not deep enough. The T-4's are way too small for any decent mid output. They give a great front stage for high and tweets though.

The pics are up, please let me know if the page is working.
-Jerry

exalted512

i got a "page cannot be found"
you can make your own cardomain site at www.sounddomain.com
it automatically makes your pictures smaller
just a thought
-Cody

LittleCar_w/12s

I think that's the last straw... I am going to run DNS externally until I can buy a set of real IP addresses... for some reason the DNS doesn't route through my router properly, which means all kinds of headache.
All that's left now is to figure out why my IIS keeps shitting itself.

Ok, I'll re-do the DNS and re-post in min or two
-jerry

LittleCar_w/12s

Ok, my DNS changes are done, and IIS is still running (amazing), so try it now.
-Jerry

exalted512

no go...
same thing
-Cody

AustinKP

Jerry,
Try the program "GuildFTPd FTP Deamon" It gives you much more control over the permissions for each user, etc. You can also watch what they are doing on your ftp server and ban addresses, etc. It's a free download. Try download.com or sourceforge.net. If you can't find it, let me know, and i'll give you a login to my ftp server. Also, goto www.no-ip.com and set up a free account so you don't have to remember your IP address. They also have a free download of a small utility that automatically checks your machine's IP address and updates it at no-ip.com in case your IP is dynamic, i.e. Cable modem, DSL, etc.
Any questions, let me know.
-Austin

LittleCar_w/12s

Oh well... I am having problems with this server... perhaps it's that I can't afford the virus software to run on a server to keep it from being eaten alive....

Well. I'll look into posting on cardomain... may be easier, unless.... I could post them to a new thread here!

-Jerry

geolemon

Originally posted by LittleCar_w/12s
--- well.. I am looking into the pioneer that adjusts timing. That way the rear speakers are more effective.

Effective...
At what?

--- Man, you just come to houston and help me fit something in that 4" space buried in my dash... or the limited floorspace that would simply eat any power i put through it.

I'd completely abandon that location, short of entertaining it as another potential option for a tweeter location... which probably even still isn't a good one.
It's fundamentally not going to perform well - mostly it physically won't be able to produce bass - not due to the driver, as you could have a subwoofer installed there... but because there's nothing stopping both the front and rear sound waves from reaching the interior of the car... the half-shell of a dashboard effectively being "the baffle"... so how low can you go?
It's not good, very fundamentally simply not good.

I'd explore other options...
Kickpanels are the default "ideal" idea that pop into mind, unless there are some physical or ergonomic reasons that prevent that.

Door builds would be another option with about as much fabrication as the kicks, if that were so.

Sure, most of us have it easier...
Don't be mad at us, be mad at the manufacturer's marketing department that designed your stereo, damn them for not having audiophiles - or at least acoustical engineers on that design project.

And consider this -
Even though most of us DO have it easier than it sounds like you do...
Most of the serious audiophiles still abandon their "better than what you have" stock locations in favor of custom fabricated locations, often kickpanels.
Just ponder that. Why?

--- I am designing a enclosure and deck design geared to direct all the subs' sound energy into the cabin in a linear fashion. It will aslo fine-tune the direction of the rear speakers and include built in enclosures for them.

Sub-bass is inherently omnidirectional.
Unless you are driving one whopping sized vehicle, one single wave can't even exist inside your interior at any given moment without compression.
In fact, this very phenomenon is known as "cabin gain", is inherently tied to these sub-bass frequencies, and is the very reason that big bass in a car is possible.
This phenomenon means that when the bass hits, essentially the entire cabin is pressurized uniformly.

What you really need to worry about are other issues...
Distortions, harmonics, things vibrating near this pressure source...
While the actual bass fundamental will essentially be omnidirectional and omnipresent (ie. you can't tell where it's coming from), these higher-frequency distortions and anomolies (keywords: higher-frequency) won't be, and your ears will be able to pick up the vibrations and distortions.

Enclosures for the rear speakers would be a must-have, otherwise the subwoofer would be playing air-paddleball against them, which certainly doesn't compliment their sound quality, since the trunk is essentially it's own sealed-off airspace with the rear speakers plugging up those potentially convenient holes.

Well.. I hear what you're saying... just can't do that... I don't really have room in the front for all that speaker, considering I have a little car. I'm not sure what in-the-door speakers would sound like, but given that they would output perpendicular to the front stage at shin-level in my car...

Sound is really omnidirectional.
It's not a laser...

The speaker does move like a piston, and the momentum of the pushed air does lend to a bit of directionality, the speaker having a slightly different on-axis response compared to off-axis...
But speakers can be designed to yield smoother off-axis response than on-axis, for car audio purposes, for the very intention of putting them in doors, where they would be listened to at greater angles, off-axis. The Adire Koda set is one.

Perhaps someone on this forum can discuss the design, or post response plots showing various on-axis/off-axis measurements, for Polk's speakers? Likely, one set might be better designed for off-axis use than another.

what's the advantage over rear speakers???

Really, just about everything.
Sound quality.
Mostly imaging.

Go to a concert... get up nice and close to the stage, front and center.
Close your eyes.
Where's the sound coming from?
If you turned around, standing in place, with your back facing the stage... you'd feel a bit uncomfortable, wouldn't you? People giving you funny looks... and it would sound different too, wouldnt' it? Your ears are shaped to catch sound coming from in front of you... maybe more importantly, your subconscious is comfortable with, as it expects, sound coming from in front of you.
Sounds coming from behind you are psychologically disturbing... your instinct is to turn to face them. It's stressful, rather than relaxing, having sounds coming from behind you. Psychological.
Consider it audio Feng Shui if you like, from that respect.

Also, the sound is travelling further, reflecting off and being absorbed by different objects, surfaces, on it's way to your ears... which will not receive that rear sound the same as it would receive front sound, due again to the shape of your ears.
Delay, to align the rear waves with the front waves won't really get you too far, although you could minimize the "comb filtering" effects...
However, again, bear in mind this doesn't equalize the front sound with the rear sound... each will have it's own acoustical characteristics, and that will lead to poor combination.

Most importantly, if you had just rear speakers in your car, and you closed your eyes..
...it just wouldn't sound like you were "at the concert".
There would be no illusion of a sound stage, no imaging.
More of a "band in the back seat" sort of effect.

I'd take the door panels off, the kickpanels... a little exploration of your front area.
It doesn't need to take much work to fabricate some great locations, that will actually allow your speakers to work as intended.

geolemon

Originally posted by LittleCar_w/12s
Also, what would it sound like for passengers in the back seat if I had none?

I addressed this in that article I posted earlier, in the "frequently asked questions" section.

To rehash:

How often do you have rear seat passengers?

Would you compromise your front-seat sound quality - where you inherently always are - for the potential benefit of the rear passenger?

Do your rear seat passengers demand high levels of sound? That would be rather big of the freeloaders, wouldn't it?
I've personally never had passengers in my car that demanded sound of any sort... most aren't audiophiles, and even the ones that were wouldn't know what to expect to begin with.
I'm an audiophile, and when I ride in other people's cars, I have no expectations. Do you?

So, back to that question...
"Would you compromise your front seat sound quality..."
Would you... for people that not only aren't there much, but don't have expectations - in fact respectfully don't have any right to (what - are they going to refuse the ride? ) - of audio in the car?

And with respect to all this...
What's preventing them from hearing your front speakers?
Their heads are just a couple feet - literally - behind yours.

Rear speakers can even be a detriment to your rear passengers...
If you are trying to have a conversation in the car, you may not realize that the speakers in the rear - which are inherently inches from their ears - are pretty loud, and you are not facing them... they may be in the back going "What? What? What?"

Not to mention, all the rules that apply, for why the rear speakers aren't good for you in the front seat, apply to the rear passengers as well.

In fact - with your "only rear speakers" scenario...
Imagine what THAT would be like for the rear passengers.

Multi-speaker stereos in cars weren't designed by audiophiles.
Only recently, with relationships such as Chrysler partnering with DLC to develop custom equalization have acoustics really been considered seriously.
Even systems like the Mark Levinson Lexus systems are "lipstick on a pig"... Mark Levinson, eh? When did he start making small car audio speakers? Where's the "Mark Levinson" amp? etc.

Up until today, these speaker systems were designed by marketing departments, who use them to sell cars.
A "multi speaker" system looks more impressive on a window sticker to a layman.
The layman doesn't think to himself "....but music is only recorded in 2-channel stereo", or "what about the pathlength differences, and absolute arrival times, or already difficult interior acoustics?"
No, the Layman is impressed, and it pushes him one step closer to purchasing a car... the multi-speakers did their job, and they haven't even been powered up yet.

Don't perpetuate acoustical mistakes implemented by the marketing department. :cool:

neomagus00

Originally posted by geolemon
Sound is really omnidirectional.
It's not a laser...

well, at least for mids and subs; tweets are pretty directional

But speakers can be designed to yield smoother off-axis response than on-axis, for car audio purposes, for the very intention of putting them in doors, where they would be listened to at greater angles, off-axis. The Adire Koda set is one.

cdt's stuff has what they call 'contoured dispersion' too

exalted512

Chris,
I tried posting a link to your article about caps, batts, and alts a while ago and it came up as file not found--also tried the link you posted with the same results...did you change your website up or???
-Cody

LittleCar_w/12s

Ok here are the pics posted to my new page at sounddomain:
http://www.sounddomain.com/memberpage/592675

after thinking about it... rear speakers aren't really a priority for the driver, but will be for the rear passengers. I have decided that I am not going to put them in the rear deck. I am going to mull over ways to have a set facing the rear passengers from maybe the pillars for their imaging, as it really is noticeable from the rear of the car v.s thefront.
Should I have mids in the sides, then tweets and maybe highs in the pillars? I have no problem with fiberglass and plastic work.

As for the front, I am not sure what It would sound like to have speakers from the kicks or doors in this car, so I may rig a cheap speaker up to the h/u and tape it in place (with an enclosure of course) I have some cheap radioshack 4x6's that'll do the trick.

Still looking for anyone who has pics of a small leg-room car that has doors or kicks installed. I haven't had much exp with smaller cars that didn't have factory locations.

My logic behind the rears at midpoint in the car is that I can fade them to 0 and then up them for passengers if they want. I guess this would be like a miniature of what one does in an SUV.

-Jerry

exalted512

after looking at your car heres what id do
tweeters in the panel that runs up your windshield
only problem is try to get it as straight up and down as possible so your soundstage isnt at your waist
or you could try to use your stock speaker location and try to make it work to where the tweeter is straight up and down
i cant find anyone who makes kick panels for a lemans
so im guessing youll have to make em yourself
id take the kick panels off, look at what you have behind it...mine have a hole in the metal already...id put them as close as factory as possible b/c you have a small car...slightly angled toward the seats
made it out of MDF and cover it with the same color carpet as the floor
-Cody

LittleCar_w/12s

Ok guys here's the update:
I snipped the leads to the rear location off the decks' pigtail, then connected about 6ft of lead to them. I have a set of radioshack 8ohm 4x10's that I had literally turned the box inside out and made an enclosure for back when I had a townhouse and used them for side speakers. I connected those to the leads and had some fun moving them around the car.

Test 1: Kickpanel and door facing towards console:
Absolutely unacceptable. Like I had guessed, it ate every bit of power I put to them and little output to the cabin.

Test 2: Placed on the kickpanel area, but facing straight back to the driver's seat:
Very nice output, clear and crisp. The location does require that I have something up top to bring the stage up (I was able to test this cause I could fade to just them on the rear channel.)

Test 3: Same location, facing slightly up:
Not much improvement over 2, but was a more efficient location for higher mids.

Cons: since the door would be an impossible place to mount a pod, I will be making f/glas ones for the kicks. The drawback is that I am limited by width because they need to face back. MAYBE 6", but that would push it. The 4x10" is wide enough, however, I can work slightly larger on the driver's side, ad I can push the 2" thick harnes to the rear of the speaker. The computer happens to be mounted right where this location is on the passenger side. I may try to move it, but that harness is f*ing HUGE.

As for the rears:
Test 3: rear stage mounted rearfacing on the window pillars(behind driver's door)
All I can say, is that the timing is absolutely awesome. With just the front speakers in the floor and the T-4's, the rear passenger imaging/stage is lacking, so I tried this spot. While I realize that I will not be able to mount 4x10"s there, I will at least place some highs and tweets here (the mids are sufficient from the front.)
The best part, though, is that:
when the rear-facing rears are in, it doesn't overpower the front stage, and the timing makes it sound like the front stage is going past you then reflecting, then returning to you. This is good, since in my car, the front stage STOPS at the driver's seat... NO sound gets to the back and returns. This really sound's like surround sound, not rear fill. I turned it up and was like "Holy crap!" :eek:

Well, I am pleased that I found a set of locations to work well, now I just need component rec's for the front:
up to 6": for floor, I think I will want a 3-way set down there, as the mid can shoot back, then Ill put the high then tweet on the curve that comes down from the dash to the floor to improve imaging. Amazingly enough, the little T-4's sound great with that little help from the floor, so I will only need high (maybe) and tweets at the top.
For the rear: I will need at most a 3" high and tweet set. Currently I am going to temp. mount the high/tweet components that I have salvaged from my sony 6x9" 's pole piece here for directional testing. They're free, and the 2.5" high is a sealed design so I will not need an enclosure until I get a better set.

If you have any suggestions, keep posting, I am listening
(Yall got me to abandon the rear locations.. what'll be next?)

-Jerry

LittleCar_w/12s

Oh I forgot to mention I will be powering this location with a kenwood 50x4 amp that has adjustable xovers for either high or low (how convenient?) All I have to do is replace it first so I can pull it off the subs

Do you think it would be ok to mount the amp in the rear, say between the rear seat and the front (relative to car) of the sub-enclosure? I realize that thiis is a lot of wire, but I don't really want it under the driver's seat. I have air ducting there in the floor for rear-passenger heat, ant that makes it a bi@tch to mount there. While I could make a platform mounted to the seat rails for this.. at that point I could have run 6 sets of wire to the back and have it nicely and more accessibly mounted.

Opinions?

-Jerry

exalted512

as long as nothing is going to rip the wires out and it has space to cool, i see no problem
everything sounds good--glad to hear its coming together for you
-Cody

geolemon

Originally posted by exalted512
Chris,
I tried posting a link to your article about caps, batts, and alts a while ago and it came up as file not found--also tried the link you posted with the same results...did you change your website up or???
-Cody

Batteries, capacitors, alternators:
http://www.betteraudio.com/geolemon/newmain/battcapalt/

Absolute phasing, pathlength and arrival time differences and their effects:
http://www.betteraudio.com/geolemon/phasing/phasing.htm

Our server was down a couple times last month, for about a day each time - once because of a DC-area DSL failure, once because of a hardware failure on our part.

exalted512

yeah i got back on the next day
-Cody

LittleCar_w/12s

Hehe... If i could keep my IIs from crashing on my server...

Anyway... here is a ? I posted in the home audio section about the tweeters for the rear, if you have any ideas let me know:
http://clubpolk.polkaudio.com/forum/showthread.php?s=&threadid=18625

And I have good and bad news...
Good news is both of the guys took 4years in prison for the multiple car burglaries
Bad news is: the $1400 the guys did may not show up... but I can still take em to court

-Jerry

neomagus00

wow... at least they got some of what they deserved... bummer that you may not, however...

geolemon

Originally posted by LittleCar_w/12s
Anyway... here is a ? I posted in the home audio section about the tweeters for the rear, if you have any ideas let me know:
http://clubpolk.polkaudio.com/forum/showthread.php?s=&threadid=18625

Home audio is a whole different world.. but most of the same acoustical rules apply.

Bear in mind, when you are talking about home audio, you are talking about two completely distinct groups of people, whose worlds don't align:
Guys who listen to music - ie. home stereo
Guys who watch movies - ie. home theater

Remember, music is recorded in stereo... all the high-end home audio guys who build systems for listening to music build simple, 2-cabinet systems.
You wouldn't find a home audiophile entertaining the notion of adding rear speakers for his stereo system.

For home theater on the other hand, you are building a system that's going to reproduce the sound that's recorded on a movie...
With DVD's, you are talking about 5.1 recordings rather than stereo.
That's 5 separate full-range channels of sound, and the recording process itself is responsible for controlling what sound comes from what speakers... and the majority of the time, the recording is engineered so no sound comes from the rear.

So, your decision to run rear speakers in the home, IMO really boils down to a very very simple, very high-level question:
What are you building this stereo for?

LittleCar_w/12s

GeoLemon,
You misunderstood I think. I was asking the home audio guys if there was a small version of the film dipole tweeter that I run at home that would work in the car, or any better dome-tweeters they know of.
Also, I am making an enitrely separate rear stage in my car... It will be rear-facing, for the rear passengers... and only will consist of highs and tweets. The mid will come from the front pods I will build, which permeates to the rear ok.. but the highs and up NEED to be restaged for the back as well. This is simple enough, and I've already tested it for compatibility with the front stage. (the timing makes it at most sound like you are in a room instead of a car, and is actually pretty clean.)

So to rephrase the question:
I tested a two-way pole piece from my dead 3way 6x9's (one stiff-cone high, one metal-dome tweeter) and compared it to my in-home dipole FILM tweeter. The dipole had great superclean response. The stiff-cone mid has OK response, but is a little hollow sounding. the AL-Dome peizo tweeter seems to only put out the smallest of the highest freq at MAX power from my home amp. Meanwhile the dipole is very loud at this point (actually hurts!)
So:................................................................
IS there a better type of dome tweeter that has REAL output?? or should I try to find a nice film-tweeter in a small size? I will still have a small high driver, (not this piece of crap I am testing with salvaged from the sonys). What is Silk-dome tweeter.. etc?

geolemon

Originally posted by LittleCar_w/12s
I was asking the home audio guys if there was a small version of the film dipole tweeter that I run at home that would work in the car, or any better dome-tweeters they know of.

The challenge with running a dipole tweeter in a car, is how to mount it.
In a home, it mounts on a small baffle (if it's tweeter-only, a very small baffle )... both the front and rear of the baffle open to the listening space, and very important, the baffle face is perpendicular to your listening pathlength.
In a car... dipole?
Interesting, something that I've even pondered... but haven't really thought of a good way of implementing, as the baffle would need to be attached to something - and unfortunately, likely the side of the baffle.

So to rephrase the question:
I tested a two-way pole piece from my dead 3way 6x9's (one stiff-cone high, one metal-dome tweeter) and compared it to my in-home dipole FILM tweeter. The dipole had great superclean response. The stiff-cone mid has OK response, but is a little hollow sounding. the AL-Dome peizo tweeter seems to only put out the smallest of the highest freq at MAX power from my home amp. Meanwhile the dipole is very loud at this point (actually hurts!)
So:................................................................
IS there a better type of dome tweeter that has REAL output?? or should I try to find a nice film-tweeter in a small size? I will still have a small high driver, (not this piece of crap I am testing with salvaged from the sonys). What is Silk-dome tweeter.. etc?

Lots and lots and lots of dome tweeters have tremendous output.
Cadence makes a component set - the Neo - I swear it could cause earbleeds from it's output level. It sounds good as well.

Possibly fundamentally at issue here, are the types of tweeters you are considering.
Soft dome tweeters typically are laid-back, even less efficient.
Hard dome tweeters typically are very efficient, some even say aggressive, bright.

The pole piece in a 6x9... face it, 6x9's aren't marketed to audiophiles. They are marketed to people that don't realize you shouldn't have two discreet types of tweeters operating together (playing the same frequencies). The components in a 6x9 are not likely to be high-fi quality.

Piezos aren't usually high-fi stuff either, but you can find some odd exceptions. I've got some decent sounding horn compression drivers made by CTS here - they actually use Piezo elements - I purchased them intentionally because they were less efficient than their traditional compression driver counterparts.

You might search places like:
www.madisound.com
www.zalytron.com
www.partsexpress.com
These places sell raw drivers. You might be surprised how inexpensive raw drivers can be.

Of course, you can't expect to just buy something and have it match... first priority is locating a 4 ohm tweeter.
Second priority is discovering how overefficient/underefficient it is - and building a proper L-pad for either it or the mid, to bring the efficiency back to where they blend with each other properly.

Also, I am making an enitrely separate rear stage in my car... It will be rear-facing, for the rear passengers... and only will consist of highs and tweets.

The problem with this strategy is:
How will you prevent the sound coming from these rear speakers from interfering with your front speakers?
Same issues as stated in that phasing article.

Also note (also in that article) that the higher the frequency, the greater the number of issues... the "comb filter" effect yields more and more cancellations and interference nodes as the frequencies increase.

I mention this, because you state you plan on running only tweeters in the rear. You might want to rethink this... or end up simply compromising the sound quality at every listening position in the car.

My admittedly personal opinion is... if you aren't looking to accomplish anything better than "sounds OK"... why spend money at all? Add a small sub to a stock system, and you have "sounds OK".

As mentioned earlier... passengers don't have any expectations of sound quality - none at all (do you, when riding in other's cars?).
Further, they aren't giving you any money to cater to them.
Optimize your SQ for your seating position.
Anything else that you build in will simply be compromising that sound quality... and won't even yield superior results for them either.
I'd skip it. Focus on yourself. :cool:

If you feel like later experimenting, and seeing if you can add these speakers...
...then make it a project, later. It's truly only at that point where you can set up that experiment, and witness what degradation that causes to your sound quality and imaging.
Right now (pre-install), you don't have a baseline.

Like any experiment, you can only manipulate one variable at a time, or unavoidably lose the ability to answer which variable caused which effect.

LittleCar_w/12s

Geo:
You are definitely right about optimising the sound for the front. I will have all of the front set to front channel, and will simply put fade to front when I am alone or have 1 passenger. When I have passengers, the rear stage is terrible... so I am going to put something simple togeher to help it... not saying I am going to spend out the rear on the rear stage.
As for the tweeter ?'s If I buy something nice, it will go up front first
Thanks for all the info. I guess there are lots of options out there, and I will just have to toy around with them.

--Jerry

exalted512

thought about just buying a DIY driver for the rear and bandpass it at like 100k-3k?
-Cody