Lets talk SQ

[Buck 5,000+ posts]

I've been reading a ton on SQ. I'm trying to understand more about phasing. I'm not sure if this is phase or not, but the sound waves have high peeks and low dips, and I think this is related to the polarity of the speaker (+ and -). - moves in, + moves out. So the goal would to be to have these waves not cancel each other out. So say theoretically, if I placed 2 of the same speakers directly in front of each other without the polarities switched, then many of the frequencies would cancel out, right? So, I'm having time comprehending how to correct this in a vehicle. Do I base this correction off of the location that I'm trying to get the best SQ at(aka my ears)?

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[PatFitz9 10+ year member]

Don't point the speakers at each other, point them at the listener //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[James Bang 5,000+ posts]

the speakers might be playing in phase according to their polarities, but will the sound be in phase when they reach your ears?

 

[DEdwards 10+ year member]

http://books.google.com/books?id=LoXH1YkyhUUC&pg=PA54&lpg=PA54&dq=ACOUSTICAL+ABSOLUTE+PHASE&source=bl&ots=FDM0fcnUNo&sig=P3VS2GkuDzM9eaHFAxtRBg2vMAs&hl=en&ei=xJIESvalI8SktgfzypT6Cw&sa=X&oi=book_result&ct=result&resnum=7

 

[pjhabit 10+ year member]

Mechanical phase & acoustical phase are two different things. There could be any combination of polarities that'll result in absolute phase. Use phase check tracks & try different combinations to find what sounds best at the listening position.

 

[Buck 5,000+ posts]

bump any more explanations? It's summer now and I'm actually going to start working on this stuff.

 

[FoxPro5 5,000+ posts]

How many more times to you need what's already been said repeated?????

Speaker A: ~~~~~~

Speaker B: ~~~~~~

^ in phase electronic phase (both 0* or 180* polarity; not one 0* and one 180*).

Speaker A: ~~~~~~

Speaker B: ~~~~~~~

^ in phase electronic phase; out of phase acoustical phase.

In the end, it's all about acoustical phase, really.

 

[bballer123 10+ year member]

Phase is a biotch! Like said above, acoustical phase, when it reaches your ear, is VERY hard to get RIGHT. It can be done to a good level without oodles of work. Guessing by your original post, I would say the "good level" would be nice for you. One quick thing for you to do is measure how far the woofers/mids/tweets are from your ear in relation to the left and right channel. This gap can be somewhat closed by placement of the components, but most of the time requires some Time Alignment (delaying the signal of one channel or component.) This will help the sounds (in ideal situation) arrive at your ear at the same time. That is the skinny of it without getting into it toooooo much. There are years and years you could study to learn more about it, but it is very tedious and impossible to control (perfectly) in a car. Hope that helps and not hurts you!

-Matt

 

[Buck 5,000+ posts]

Phase is a biotch! Like said above, acoustical phase, when it reaches your ear, is VERY hard to get RIGHT. It can be done to a good level without oodles of work. Guessing by your original post, I would say the "good level" would be nice for you. One quick thing for you to do is measure how far the woofers/mids/tweets are from your ear in relation to the left and right channel. This gap can be somewhat closed by placement of the components, but most of the time requires some Time Alignment (delaying the signal of one channel or component.) This will help the sounds (in ideal situation) arrive at your ear at the same time. That is the skinny of it without getting into it toooooo much. There are years and years you could study to learn more about it, but it is very tedious and impossible to control (perfectly) in a car. Hope that helps and not hurts you!
-Matt

Ya man thanks. Ok I was just trying to understand phase. I know I needed to do time alignment, but wasn't sure how that was related to phase. I see now, thanks man.

Ok if I do time alignment, what else is there to do to help with phasing?

Lol, please be patient with me I'm just trying to learn.

//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[James Bang 5,000+ posts]

iasca discs track 3

http://www.caraudio.com/forum/showthread.php?t=339117&page=2

if links don't work, oh well.

 

[bballer123 10+ year member]

Ok if I do time alignment, what else is there to do to help with phasing?

Well, assuming you have the components in one centralized area (kick panels) you are going to be pretty good. This is all theoretically of course. If you want perfect acoustical phasing, car SQ is nowhere near it. BUT, having things aligned from the beginning point (before interacting with the surfaces of the car) you are doing yourself a lot of favors.

If you are having them separate, that takes a bit more work (depending on how high your goal/standard is.) Ideally, you would time align each driver on one channel and do the same on the other channel. It is very tedious though. One of the simplest ways is to do what I said above. Start with them in the kick panels and then time align them. I think you won't mind the results.

-Matt

 

[James Bang 5,000+ posts]

so i've been thinking about time alignment and point sourcing mids and tweets

say you have a passive set where mid and tweet are mounted very close to each other

BUT

2khz + isn't affected as much by T/A compared to freqs below 2khz.

Wouldn't that give you a less favorable image/stage?

/thinking out loud.

 

[Buck 5,000+ posts]

so i've been thinking about time alignment and point sourcing mids and tweets say you have a passive set where mid and tweet are mounted very close to each other

BUT

2khz + isn't affected as much by T/A compared to freqs below 2khz.

Wouldn't that give you a less favorable image/stage?

/thinking out loud.

How are they not affected as much? I'm not questioning whether they are or not, but how exactly would that work. Would it be because of the higher frequencies and more waves per given distance?

 

[stuckinok 5,000+ posts]

Less talk more install

 

[Buck 5,000+ posts]

Less talk more install

I don't have my damn truck because nooooowww they think the mother fucking frame might be bent so they get to keep it for another fucking month while I sit here on the damn couch talking about what I could be doing.

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