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BIG-SMOOTH
11-22-2007, 04:17 PM
I just purchase a new car yesterday that has 6.5" inch mids in the lower, front part of the doors and a set of tweeters in the panels right by the mirrors at the lower part of the A-pillars. I will be using a Clarion DXZ775USB for my source unit. The head unit has a 3-band parametric equalizer and time alignment, but I have no intention of using any other processing.

Would it be easier to get a decent sound stage by using comps in the stock locations or putting both the mids and tweets down in the doors? I'll be using pioneer REV speakers. Either the TS-C160R or TS-D601P.

dvrmstrng
11-22-2007, 04:18 PM
whoa pottsville....how far are you from like schkyull county?

azbass
11-22-2007, 04:37 PM
I would install the tweets and mids in the factory locations, then you can adjust everything with the T/A, etc.

BIG-SMOOTH
11-22-2007, 04:37 PM
whoa pottsville....how far are you from like schkyull county?

Pottsville is in Schuylkill county.

Etac
11-22-2007, 11:32 PM
i personally dont like tweeters up high but its personally preferecne - throw em in the kick if you can and see if you like that better first

i dont know how your tweets are designed but i only had to make three little screw holes to put em in the kick so even if i took em out - its hardly notcieable unless you really look for it

with the tweets furtehr away from you - they tend to blend better with the mids - hard to localize - and sound better at a distance IMO but this can also be accomplished with good tuning..

grampi
11-23-2007, 12:24 AM
Actually it's best to mount the tweets as close to the mids as possible. If the mids are in the doors, I would also mount the tweets on the doors right next to the mids.

azbass
11-23-2007, 12:25 PM
he has time alignment.. he does not need to mount the tweet close to the mid...

Gary S
11-23-2007, 02:11 PM
Generally, if you can get a good install/solid, rigid sealed enclosure (or infinite baffle such as a door), here are how the locations stack up for imaging and sound stage:

best - Both drivers in the kicks

better - Midbass in doors, tweeter in kicks

good - Both drivers in the door

fair - Your factory locations


Time alignment will only fix things for one listener... the standard for car audio and especially contests is to achieve good sound for both front seats. Additionally, balance and level controls will have the same affect as time alignment. Time alignment is not worth your time, and there is no replacement for good speaker placement.

azbass
11-23-2007, 02:20 PM
here are how the locations stack up for imaging and sound stage:

best - Both drivers in the kicks

better - Midbass in doors, tweeter in kicks

good - Both drivers in the door

fair - Your factory locations

yeah no..

grampi
11-23-2007, 02:45 PM
Generally, if you can get a good install/solid, rigid sealed enclosure (or infinite baffle such as a door), here are how the locations stack up for imaging and sound stage:

best - Both drivers in the kicks

better - Midbass in doors, tweeter in kicks

good - Both drivers in the door

fair - Your factory locations


Time alignment will only fix things for one listener... the standard for car audio and especially contests is to achieve good sound for both front seats. Additionally, balance and level controls will have the same affect as time alignment. Time alignment is not worth your time, and there is no replacement for good speaker placement.

I agree with your speaker placement ratings, but balance and level controls do not have the same affect as time alignment. Balance and level controls adjust the volume, while time alignment adjust the timing of when a particular speaker will receive its signal. Two completely different things. And it depends on the HU for how many seating positions time alignement will adjust. Most HU's will only adjust for one seating position, but the Alpine CDA-9887 will adjust for up to 6 seating positions simaltaniously. It's kind of like creating an tiny concert hall in your vehicle. Time alignment is well worth your time especially in situations where it's just not possible to locate the speakers in their ideal locations.

2kchevy06civic
11-23-2007, 02:49 PM
he has time alignment.. he does not need to mount the tweet close to the mid...

this man speaks truth

azbass
11-23-2007, 02:53 PM
my tweeters are on the dash, and my mids on low in the kick on axis with the seats.

but my whole sound stage sounds like its out on the hood.

:)

xtremekustomz
11-23-2007, 06:55 PM
I'm gonna throw my $.02 in. Obviously doors aren't the best place to put them because of the pathlenth differences, but if you have to put them there, I'd be more set on using an eq to fix things other than time alignment. It can actually narrow your soundstage from left to right. I've got an audiocontrol dqs I really need to get rid of so if you or anyone else needs one let me know. Also, kicks are the better place but if I were you I would try different locations for everything and find what works best in YOUR vehicle, not someone elses.



Here's a great post by Mark Eldridge over on CarSound concerning PLD.

Originally posted by Mark Eldridge:
Hmmm... path length differences... You might as well get that signal alignment device cause I'm not going to help you... smile.gif

Yea, right!

Actually, I'd recommend looking for past threads on the topic, in addition to what we discuss here. There have been a lot of threads on this subject in the last year or two, and you can find them in the archives and just by searching for threads on path lengths, imaging, staging, etc. Also, buy a copy of the Autosound 2000 Tech Briefs, and read tha articles in that collection. Between those two sources, you'll have more information than you can probably find form all other sources combined. smile.gif

The real skivvy is that you want to minimize the differences, for a lot of reasons. Especially in the mid-bass through the midrange regions, the difference between left and right pathlengths is CRITICAL! In fact, between 100 and 400 Hz, the angle of the speaker won't even matter, as imaging cues are almost 100% determined by path length, not by intensity differences. Above 2000 Hz, imaging cues can be controlled by speaker angle and other intensity controlling techniques. Path lengths above 2000 Hz are not critical.

As far as the path length differences between the mid-bass driver, midrange, adn tweeter on a single side, you'll probably never get them exactly the same. The real problems with path length differences here will be int eh frequency and phase response in the crossover range. Signal alignment can help some here, as long as the speakers aren't too far from each other. It's more acceptable to have a mid-bass amd midrange separated than to separate the mid and tweeter. The mid-bass frequency range can make a difference in the perceived stage depth,a dn the center image stability. But, the upper midrange and high frequencies are responsible for the stage height, width, and depth, as well as image focus. Keeping these frequency range drivers close together will be a lot easier to control all the variables than separating them. If you need additional stage height because the mid and tweeter are in the kick panel area, then add a second set of tweeters high and wide, and crossed over pretty high as well (somewhere between 8000 and 20000 Hz). This configuration is what has been used in most all fo the best sounding cars that use conventional drivers. And in most of the HLCD systems, the additional tweeters are used for the same reason.

Anyway, locate the midrange drivers first, and work with them in their intended frequency range to achieve the best overall stage depth and center image. Don't worry too much about stage height or width yet.

Next, locat the mid-bass drivers so they blend well with the mids, have solid output, and do not detract from the center image. Doors will likely not be the best place for them. They can be mounted under the dash, in the floor, in the firewall towards the center of the car from the kick panel, or where ever else they work, adn can have a large enough enclosure.

The tweeters are the easiest. Mount them as close to the mids as possible, and make sure they give you the width and height you want, and help to focus the image performance. If you need the additional height, add the second set of tweeters.

Path lengths are a different animal. They're kind of like the impedance of a woofer. Industry wide, we call a speaker a "4 ohm" or "2 ohm" speaker, when in reality, it is only really that impedance at one or maybe two frequencies. That's the "nominal" impedance which means "in name only." The actual impedance varies widely accoring to frequency. A "4 ohm" speaker in a box may have impedances as high as 50 ohms at resonance, and as low as 3 ohms elsewhere.

Likewise, the sonic cues that affect what we percieve as staging and imaging are frequency dependent, and there is no one single number, technique, or what ever that can be used across the frequency board.

Good luck!

Gary S
11-24-2007, 01:52 PM
More on level vs. time alignment:

If you turn a simple balance control to lower the level of one side, it has the same effect as delay... one side will sound as if it is further away from you. Again, different means, but same effect as far as what you hear.

Attenuators (Attenuators include balance controls, faders, EQ's, tweeter level switches on passive component crossovers, etc.) are good enough for everything up to the IASCA World Finals.

Time alignment is just another way to get your money... along with expensive boutique wire and other non-essentials.

Speaker placement is one of the most important things for good sound, it's right up there with system design, quality of installation, and system tuning.

grampi
11-24-2007, 05:43 PM
More on level vs. time alignment:

If you turn a simple balance control to lower the level of one side, it has the same effect as delay... one side will sound as if it is further away from you. Again, different means, but same effect as far as what you hear.

Attenuators (Attenuators include balance controls, faders, EQ's, tweeter level switches on passive component crossovers, etc.) are good enough for everything up to the IASCA World Finals.

Time alignment is just another way to get your money... along with expensive boutique wire and other non-essentials.

Speaker placement is one of the most important things for good sound, it's right up there with system design, quality of installation, and system tuning.

You are absolutely right about speaker placement being most important. The problem is in automotive applications, most of the time it isn't possible to place the speakers in their ideal locations. Most people don't have the knowhow to build complex kick panel or dash mounted speaker enclosures, or there simply isn't room to mount them there. Where most people end up mounting their speakers is in the factory locations, which most of time is in the doors. This is the reason time correction is used. You can't correct imaging problems from door mounted speakers using balance and EQ adjustments only.

squeak9798
11-24-2007, 08:36 PM
Additionally, balance and level controls will have the same affect as time alignment. Time alignment is not worth your time, and there is no replacement for good speaker placement.



If you turn a simple balance control to lower the level of one side, it has the same effect as delay... one side will sound as if it is further away from you. Again, different means, but same effect as far as what you hear.

I think you need to read up on ITD and how it relates to our localization of sounds in the midbass/range area. Time arrival certainly plays a role independent of intensity ques contrary to what you suggest.

azbass
11-24-2007, 08:38 PM
guys keep in mind, hes probably not an SQ competitor..

the stock locations would be easy to install, and sound fine.. and simple tweeking at the deck would be even better.

BIG-SMOOTH
11-24-2007, 09:35 PM
guys keep in mind, hes probably not an SQ competitor..




I am definitely NOT an SQ competitor. Simply looking to put together a decent system on a relatively tight budget.

Here's what I have planned so far...

Head Unit: Clarion DXZ775USB
Front Stage: Pioneer 6.6" REV components (powered by amplifier)
Rear Stage: Pioneer 6.5" REV coaxials (powered by head unit)
Subwoofers: Image Dynamics ID8 (2)
Amplifier: Kicker ZX550.3
Deadening: 125 sqare feet of Raammat BXT and 8 yards of Ensolite

This will all be going into an '08 Hyundai Sonata.

So far I purchased the subs, amp and deadening material. I bought the REV coaxials, but I got the 6.75" premier models so I'll have to see whether or not I can get them to work in the 6.5" holes without much cutting.:crap:

mavster
11-24-2007, 11:49 PM
Hmmm,

Don't even bother using the revs off the HU for the rear, go with the normal A series pios. Your just wasting money running the revs off a HU, they love power.

The 6.75" will fit perfectly in a 6.5" opening, just make sure to use the mounting clips Pioneer supplies. They look like silver brackets, put one over the rim of the speaker hole. Then drive the screw through them.

mr burns
11-25-2007, 12:20 AM
Squeak 9798 speaks the truth. Balance control will attenuate all frequencies. Time alignment, used properly, when you have to work with stock locations is a Godsend.

Gary S
11-25-2007, 12:35 PM
I think you need to read up on ITD and how it relates to our localization of sounds in the midbass/range area. Time arrival certainly plays a role independent of intensity ques contrary to what you suggest.

- I'm not saying time alignment cannot have some benefit in some systems, only that it's not a cure-all for speaker placement.

Time alignment would be better than attenuation for midbass/bass because it allows you to keep the same/higher output levels while still balancing the speakers/drivers, but it won't do a better job for mids and highs than better speaker placement would; it won't fix poor speaker placement for mids and highs.

Believing that you can put speakers anywhere and fix any problem with EQ and/or time alignment is a poor approach. Eq/time alignment should only be considered (but not necessarily used at all!) AFTER choosing the best speaker placement you can. This is what I'm trying to get across to these guys.

The correct approach is to choose the best speaker application first... it's of much higher importance.

I've been in and around the car audio business for 22 years, even worked for a little co. called JL Audio at one point.

Squeak is an expert on audio, and even though we may argue the fine points sometimes, I want you guys to know that you could never go wrong with his advice.

Another viewpoint on time alignment:

http://www.caraudioforum.com/vbb3/showthread.php?p=2131117&highlight=alignment#post2131117

grampi
11-25-2007, 01:36 PM
Gary S

No one here is arguing the point that speaker placement isn't most important, or that you can completely correct deficiencies caused by poor speaker placement with time alignment. What I am saying is TA is a very effective tool for fine tuning a system and it's rarely possible in the automotive environment to place speakers exactly in their ideal locations. The ideal locations are usually either on the top outer corners of the dash with the speakers facing the occupants, or in the kick panels. Unfortunately, most of the time it's not possible to mount speakers in these locations. I've run into a huge problem with my own install at the moment. My mids require an opening that accept 2.8" of mounting depth, but my front doors only allow for less than 2.5". There also isn't enough room for custom enclosures on the dash or in the kick panels. If I can't find some raw mid range drivers that require less mounting depth than 2.5", I don't know what I'm going to do. I don't know why speakers have to be made so deep, or why doors are so shallow. It's almost like car makers and the car audio companies are purposely working against each other.