WuNgUn

That's just it...how do you have a setup in a car with the speakers at about 50~75cm positioned at ear level about 2~3m from the listener?
Near impossible...
Unless you run a stereo pair in each footwell or something?

My front speakers are in my doors, about where my knees are...facing each other...
The rears are just below shoulder height, and again, facing each other.

How are your speakers setup ?

MP3Car.com

 

durwood

Initially, I compromised as car audio always is but found that since you are closer ~1-1.5m the spacing between them needs to be closer. I placed a pair of widebanders on my dash moving them around until it worked. Then I built my test enclosure based on that spacing it is on my dash. If you are going to use speakers in the doors, forget trying this at all in the car. It will be a waste of time.

I prefered the original CXC filters over RACE, BACCH sounded better than the original CXC, but now I prefer the much simpler MAP plugin.

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jiggad369

Where can I find the plugin? Mind sharing some pics of the install of the speakers in your car?

WuNgUn

There are links in this thread...
And 2X on the pics!

durwood

You guys can't visualize? Don't worry about how I'm doing it. It tells you how to set it up, it's up to you to figure out where you are going to shoehorn in your speakers. Use your melon. I say test it in the home first for a reason. Test first, build second.

links are in this thread and also in the wiki.

This is all you will get from me.
http://pcfarina.eng.unipr.it/

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WuNgUn

Can't visualize this speaker setup in a car!??! Are you kidding me! lol
Sorry, no...
This is why we asked for pics...lol
Any goon can put speakers in any location they want in a car...but to make it look like that's where the speakers belong, as well as function,
well that's another matter altogether...

As for my home setup, yeah, I'll be implementing this for sure...some day.

Now, auralization in the car? This sounds interesting!

durwood

Again, I don't see the issue here. Construction is always up to the builder. Two solutions to this problem
1) Practice on your own, make mistakes, fix, get better.
2) Pay someone else to do it for you.

I like 1, otherwise you become a who doesn't learn. Learning through mistakes is a good rule to live by.

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WuNgUn

Nobody's asking you to build their car for them...
I just have a hard time seeing this properly implemented in a car without it looking like a rolling anechoic wave guide chamber!

MP3Car.com

 

jiggad369

Durwood,

This is my car:

http://images2.auction123.com/sizequ...g?webimage001l

I was thinking of positioning the speakers up where the oval clock is (up top in the upper tight corner). It would be four speakers (outer would be midranges, inner would be tweeters). It would be 4 speakers in a line.

Would this work or do I need more separation between the L&R sides? I know in your log, you practically had each side facing the person in the seat.

In the front page you stated that the speakers have to be close together at about 2m-3m from the listener but in car, we're only like 2-3 feet away. So do the speakers have to be close together or farther apart due to less space between the listener and the speakers? What is the ideal space need between the two sides? And do they still need to be 10-20 degrees?

durwood

As you get closer to the speakers, they have to be closer together. That is how geometry works to keep that 5-10deg angle.

Here is the problem, just like stereo, there is an optimal setup with the listener centered directly between the speakers.

So, you could set it up so you are centered or you can attempt to widen the sweet spot. The third option, which I'm unsure if even possible, is to attempt to correct for offset off center seating. The first and last options make it a solo experience ruining it for other passengers, the 2nd option might work for all passengers.

I cannot say which way is the best. It's all compromises. I have a theory on how to accomplish the 3rd option, but until I test it I don't have details. I had outlined it at electro-music.com, but that is as far as I got with it.

A variation on this whole concept that seems better suited for a car is "optimal source distribution". Look it up and hoepfully you can visualize and understand why. The limited info I found also showed Alpine and Yamaha did some research in this area and marantz and yamaha appear to be using this concept in their "soundbar" speakers.

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WuNgUn

I'm gonna mess around with Pristine Space, with the BACCH loaded up...
PS gives a multitude of adjustment possibilities...maybe it can be tuned to better reflect the speaker placement in my car...
It also give discreet control over 8 channels, so I should be able to independently setup and control the rear L/R cahnnels as well.
Problem is, I have to do all this testing while sitting in the car

WuNgUn

Interesting...
Testing with a pair of desktop stereo speakers position to replicate the placement in my car (facing one another, offset listening position to the left, and lower), with the RACE impulse sample loaded, there is still, remarkably, and percieved widening of the stage! I can wet/dry the impluse on and off and easily discern a wider field. Even with the LP almost directly between the speakers firing plane, the stage is fairly enveloping...
With the impulse off, the stage seems to move to a small point in front of my nose.

I'm going to test further with a 1:1 scale trianglation of the speakers/listening position (right now it's about 1:2).

jiggad369

The only problem I'm seeing is the positioning of the speakers in the car environment. I'm a newbie at this and a complete illiterate when it comes to audio mechanics.

I did some quick calculations based on the 10 degree separation and found out that the speakers need to be ~3 in. apart, which is very close. This means that I either have to put them in front of me or put on top of the clock (pic in my previous post). If I put it in front of me, no problem. If I place them on top of the clock, I'll be about 1.5-2 ft. away from the optimal listening position from where I should be (based on the 10 degree method.) What are the cons for this? Losing the entire effect of this process or just losing top/high range?

hithere

What happens to midrange vocals under this crosstalk elimination scenario? Vocals are often dependent on information being simultaneously broadcast from both speakers...I can see an eventuality where, without removal of like information between both speakers from the processing loop, such information would be subject to the cancellation being performed (basically, the same effect as when you reverse phase on a single midrange driver in a stereo pair...you cancel a lot of the vocals which may create the illusion of greater separation and stage depth by increasing left/righ bias and attenuating vocals)

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I have too much time and too little aggravation in my life, so I built a carPC. ;)

durwood

I prefer to think of it as controlled crosstalk vs cancelation. With the mosc plugin, it is simple processing. In phase info comes from the center just like a sololist should, out of phase whether 180deg or somewhere in between is moved to proper position. It's more like an L+R/L-R setup and mimics 3 channel with only two speakers.

It works kind of like this
L-R, L+R, R-L

It's like flipping stereo inside out. This works opposite of crossfeed for headphones (where there is no crosstalk), but same basic principal-controlling the acoustic crosstalk. Why don't you try it for yourself? The info is there in the second post, the plugin link is in this thread somewhere but also in the wiki.

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