START HERE (All you need to know about Car Audio)

[CAMSHAFT]

Welcome to the all enveloping knowledge thread for car audio. I believe that if you read all of the post and follow the links you will find what you are looking for. If you dont find what you need then start a new thread and we will work on helping you. Also if you feel that we need to add something to this thread then let me know Thanks!


Start here, if it has ever been asked these sites explain it to the ninth degree
Basic Car Audio Electronics
Car Alarm, Car Stereo, Mobile Video, and Cruise Control Info for Installers
The Install Doctor - The Do-It-Yourself Car Stereo Installation Resource
index | AudiophileWiki

Sound Explained
HyperPhysics Concepts

Tech Briefs and Tutorials
Monster Performance Car
Tutorials | Team Audionutz
JL Audio

Audio Terms and Definitions
Glossary of Electrical Engineering Terms - Maxim
music technology dictionary, MIDI, audio and electronics terms explained!
SSA Forums: > T/S Parameters explained
JBL - Home Audio

Car Audio Forums
http://www.termpro.com/cgi-bin/ubb/ultimatebb.cgi
http://forum.sounddomain.com
CarStereos.org - appealing to the audio addiction - Powered by vBulletin
DIY Mobile Audio - Diy Mobile Audio
EliteCarAudio.com : Your one stop resource for mobile audio and electronics on the net.
ICIXSound.COM Forums - powered by vBulletin
http://www.audiogroupforum.com/csforum/
Soundpressure.com Forum - Powered by vBulletin
Talk Audio Forums - Powered by vBulletin
Team Kinetik 180db.com (Powered by Invision Power Board)
Realm of Excursion: Forum - Powered by vBulletin
SPLBassX.Com Forums (Powered by Invision Power Board)
SSA Forums: (Car Audio at its Best!)
http://www.dynamicautoacoustics.com/...p?action=forum

Car Audio Magazines
Performance Auto & Sound - The Girls - The Cars - The Life

[CAMSHAFT]

http://carstereohelp.com/stereoremovalNis0.htm

3rd Gen Alty Head Unit Removal

http://www.cardomain.com/ride/604197/6

[sammybaddy]

You should always disconnect the battery when working with the electronics in the car. I had my car taken to a local shop to connect the speed sensor wire for my GPS (Only wire I could not find), and they didnt disconnect the battery because they made my airbag light flash. They said I had to take my car to Nissan to fix it, and Nissan wanted $35/hr. I'm never going to that shop again.

This forum is very informative. If you need to reset your airbag light, see this thread for the procedures.

[CAMSHAFT]

NOISE ELIMINATION CHECKLIST

Noise Prevention

[CAMSHAFT]

Sound Damping Plan......

http://www.nissanclub.com/forums/car...tion-plan.html

[AltimaDreams]

http://www.amusicdirect.com/products...asp?sku=ACARCD
http://www.amusicdirect.com/products...asp?sku=CBURM3
http://www.highfidelityreview.com/index.asp
http://store.acousticsounds.com/sear...&section=music
http://www.amusicdirect.com/products...p?sku=CCHEG151

Also look for any Denon, Telarc, Sheffield Labs, Focal, or Alpine Discs............

One song that I love to use to test out my midbass/midrange is Cypress Hills Rock Superstar. The beginning of the song is the key. They use alot of interesting instruments.

Requiem of a Dream is a good one i listen to for some good overall sound, it's an orchestrated song, so it's fairly precise...otherwise, i'm tryin to get a good compilation goin

How can you not listen for fidelity AND bass to the 1812 overture?

Combine that with Dynamic Duo by DJ Magic Mike.

http://forum.elitecaraudio.com/showt...hreadid=130166

http://forum.elitecaraudio.com/showt...hreadid=131875

Nissan Club Audiophiles....Get with Steve and request your copy today!!!

for bass i think Woofwrecker would do the trick or Techmaster p.e.b.

Run DMC - Dumb Girl
Beastie Boys - Brass Monkey
good clean ole school bass

Coastin by DPG

[AltimaDreams]

STICKY THIS IMMEDIATELY - took this from another forum..very good informaiton..

I found this on caraudio.com from someone who got it from http://audioforum.termpro.com/ubb/ul.../t/000677.html, it's mainly tips on how not to get your car and audio equipment jacked. Sorry if this is a repost, I searched and didn't find anything, but even if it is I still think it's a good refresher

Please feel free to add more to this list!

• ALWAYS use common sense. Don't 'bump' where you live, esp. if you live in an apartment
• If at all possible, avoid putting any stickers on your car (be it performance or audio) they just scream "steal me! steal me!"
• If you go to car shows/soundoffs, I suggest removing your license plate temporarily. This will at least make it hard for people to remember your car is packing what gear(s)
• Consider getting dark limo tint and car cover. Remember - out of sight, out of mind.
• when you go to a mall or a store, turn down your system at least 2 miles BEFORE you get there. When a thief hears you bumpin down the road, he will follow you till you park and jack your equipment when you leave. Anybody who's desperate for money will do ANYTHING to steal something.
• Please Please Please install an alarm. I know about 30 people who pack thousands of dollars worth of competition-grade Audio Equipments in their SPL vehicles and they don't even have a $100 car alarm How stupid can you be..
• 'modify' your car alarm.. It might be an overkill, but I'll install 10 additional siren around the car - two inside the hood, two underneath beside the cat, two in the trunk, and four in the cabin. Thieves don't have enough time to cut all those wires while they're blaring 130bD.
• I betcha right now I can guess where you all have your alarm brains.. they're under the dash. right? that thing can be disabled in less than 5 seconds! Don't be a fool, move that brain somewhere hidden. Mine has mixed wire colors and false wires all around, Not even a professional installer can unload it.
• modify your Kickpanels to hide the hood release latch under the dash. Mine is covering the whole thing so you will have to reach inside the kicks to pop the hood. One time I took it in for an oil change it took the guy about 10 minutes to figure out where the hood release is This is extremely important so that the thief can't disconnect your +12 source and disable your alarm.
• I can't emphasize enough how extremely important security screws are. These are oddly-shaped head screws that you can get from any hardware store. Nearly ALL thieves carry a flat screwdriver and/or phillips screwdriver all the time. A hex or square head screw will definately slow them down. If your amp is bolted to the amp rack like this, there's NO WAY they can take your equipment.. but make sure your amp rack is bolted as well.
• Ask your insurance provider if they can cover your equipment.
• Be careful on who you show your system to... remember that every person is a possible thief. Even people who post here.
• Don't leave anything "interesting" inside your car (cellphone, jewelry, heck even a quarter) this will only attract passerbys that can possibly lead to theft.
• make sure all your fuses are good and have the right rating. Moreover, make sure your equipments are FUSED. In worst case scenario, after an equipment is stolen, wirings short out literally putting the car on fire.

The next time you roll down the parking lot, remember to keep them bass down cause having a system is like having sex--- you'll never know when you're gonna get jacked

Additional Tip: For those of you with websites about your ride... BE CAREFUL! That website can easily turn into a 'shopping catalog' for a thief. Try not to list personal information on the site (ie what city you live in, what school you go to). If you have any pictures of your ride, always blot out the licence plate. Also, if you have your own domain name try to use a different mailing address then the one your car is located at (ie Use a PO Box). Remember that's public information and can easily be obtained by doing a "WhoIs" report (http://www.netsol.com/cgi-bin/whois/whois).

ALSO-- Manual fuel cut off switches.....hey they cost a freakin dollar. Invest in them. Its a simple cut and splice between the fuel pump line and will piss the hell out of anyone attempting to move your car.

Speaking of the hood, Hiding the hood pop switch is a step in the right direction but will only stop petty kids who are just f'ing around in the game. The real vulnerabillity is in the line that connects the lever to the hood pop mechanism...in most cars these are routed throught the driver side fender. Pull the plastic molding back strip the insulation and get a plier to pull the wire inside and POP ....you have an open hood.
solutions? reroute the wire somewhere else or add additional lines to confuse.

The main point is no matter what you cannot stop someone from getting into your car. You can SLOW them but not totally stop. There are big holes in the side of the car covered with glass....i believe people call these windows. Since it is imposible you to stop someone from getting in one should focus on slowing them down as much as possible as well as preventing the moving/disabling of the car.

An expensive alarm won't do much for you. They are all the same with some added bells and whistles. All you really need is a starter kill, and dual stage siren....an expensive alpine alarm with LCD screens does not do anything if it can be yanked from under the dash.

BUY A PEDAL LOCK
[someone] has thought many hours about this and still have yet to figure a way around it. The infomercial is correct. That pedal is made of some hard freakin steel. And even if you could manage to break the pedal off youd have to sit with your ass facing either up or our of the car for a long period of time....not something smart to risk..

Record time sawing through a steering wheel....48 seconds.

I don't know if alarm stickers (such as "Protected by Viper", etc) is a good idea or not. Some say it's a good deterrent, some say it makes it easy for code scanners to 'unlock' your code. If somebody knows more about this issue, please shed some light...

Another security feature that you can get is Wheel Locks. http://cgi.ebay.com/ebaymotors/ws/e...item=1846139244 I don't know yet if it can be defeated, but it's worth a try.

LoJack is also a good investment. Although they run around $600 installed, you might get something in return from your insurance company just for having it. Also see 'peace of mind'

IMO, the *only* equipment that you cannot protect is your subwoofers. Whether you put a grille or not, if a thief can't pull it out, he will stab it with screwdriver. (reconing a sub is way cheaper than replacing it)

About re-routing cables such as the hood release or trunk release. How easy/difficult would it be to rerun these to some other location such as inside the arm rest or glove box? Im a very paranoid person when it comes to leaving my car anywhere that isnt locked inside of my yard with the guard dog loose. The wheel locks are good for the common theif but ive seen people who know bang similar sized sockets onto these locks and remove them, kinda like when you strip a nut and use a smaller sized socket. Thats why i use two sets of wheel locks. Not fullproof but a great deterent.

1.Changing the switch in the glove box to a keyed switch to disable the trunk button makes it still easy for you to open the trunk and a pain in the butt for a thief.
2. Two sets of wheel locks improves your chances of keeping your wheels. Bitchy if you have a flat.
3. Another hidden keyed switch to fuel pump is a cheap but sneaky method. 4. Locking fuel cap is needed due to gas prices.
5. Breaking side window and opening hood or trunk will not trigger most factory alarms. Add mercury or magnetic switches to alarm.
6. A bicycle cable lock on hood will allow the hood to open just enough for you to unlock it.

mercury or magnetic switches? where would I find these?

Magnetic ones are used in home alarms. The switch is screwed to the door or window frame and the magnet is mounted to the door or window. They come in normally open and normally closed. Radio Shack used to carry mercury switches but they no longer carry much of anything. EXAMPLES:

http://www.tanealarm.com/surface_mount_contacts.asp

http://item.express.ebay.com/ws/eBay...ERCHANDISING=1


its about 4 years old but the information is good nonetheless heres the original thread btw..

http://audioforum.termpro.com/ubb/ul.../t/000677.html

[CAMSHAFT]

Compact Disc recordings are designed for two cabinents that have all the required speakers enclosed for a complete frequency spectrum sound, which are evenly spaced apart, and in front of the listener. Notice I didnt say behind the the listener.* Because of the speakers in your car are at different places, and the listening position is not in the center of the vehicle, that creates a need for digital correction to include Equalization and T-Corr.

Now there are two factors that are easily created in studio or home environment that are tough to get in a car, those are staging and imaging.

For staging you want the width of your stage to be wider than the a-pillars, the height of all frequencies* to be above your dash at eye level, and the depth to extend past your windshield.

For imaging, in a front stage only, stereo recording, there are five images; left, left center, CENTER, right center, and right. You want the center to be below the rear view mirror and everything else evenly spaced from there.

First off having a good installation will help alot of these issues. Secondly not using rear fill will keep from having your ears being confused. Placing your speakers in H,W,D friendly locations will provide a good basis right off so that there wont need to be very much electronic changes made. In the perfect install all speakers would be placed on the dash and hidden due to Psycho-acoustics*. My car has the mid and tweet in the a-pillars, and midbass in the kick panel.

Now to get the proper images there are great tracks that IASCA has on their competition disc. With only a womens voice (no music) it allows you to adjust the T-Corr until she is "audibly located" in the center of your windsheild. Now you can use some great music to do this as well but it is allot easier to adjust only the human voice. There are also some phasing tracks that are frequency dependent that you can use as well. There is an old Alpine disc were a gentlemen walks around a stereo microphone and calls were he is, therefore were he should be on your stage. I use as many ways as possible to get as precise imaging as humanly possible.

Did this help any?

*Rear fill is bad
*with speakers in your doors your height is going to be low
*involves many factors to include how your sight interacts with what you are listening to
http://www.answers.com/topic/psychoacoustics

[CAMSHAFT]

A TRUE 3-way setup is a tweeter - midrange - and mid bass.

What this set-up will get you is an even distribution of the frequency spectrum minus sub bass.

Here is my 3-Way setup.

Hybrid Audio Technologies: A New Generation of In-Car Audio


First lets do Sound Theory 101. The audible frequency spectrum is 20,000 Hz to 20Hz. 20,000 Hz is the highest pitch cymbal that the human ear can process. 20Hz is the lowest rumbling bass drum that the human ear can process. Now companies make speakers that can play higher and lower than that, but those freqs are only detectable by scientific instruments.

A tweeter will give you anywhere from 20,000 Hertz to 1,4000 Hertz.
A mid range will play from 10K to 150 Hz.
A mid bass will play from 4k to 20Hz. .

Now to optimize your components that you have in your car you can use the crossover settings. What this does is that it makes it so that you are only getting the intended freqs in the component that it was designed to play in. Meaning, you don’t want high-pitched voices in your subs and you don’t want your midranges playing lower than they need to (this can cause speaker blow outs)

The crossovers I am about to explain are called active crossovers.

The way a high pass filter works is it lets all frequencies play above the selected freq in a certain speaker. So if you set the HPF at 2K Hz, it will play 2k to 20K Hz.

Now a low pass filter is the same way but stops the freqs at the top and lets everything below "pass through". So if you set the LPF to 100Hz it will play 100Hz to 20Hz.

Every speaker is different for its intended "sweet spot". MY speakers have the following crossover settings.

Tweets: 6.3k and up (HPF only)
Mid range: 6.3k to 250Hz (HPF and LPF)
Mid Bass: 250Hz to 36Hz (HPF and LPF)
Sub bass: 36Hz and down (LPF only)

Now a 3-Way setup is preferred over a 2-way setup, because of less reliance on each of the components to perform large amounts of musical information.

For example in a two way the crossover is telling the tweeter to do 20k to 3.5K and the mid to do 3.5k and down (however low it can handle). The thing is if you aren’t using a crossover your stuff may sound like doo doo. Furthermore it is asking too much of the mid-range.

I hope this helps.

[CAMSHAFT]

While rear speakers might seem natural or necessary to some people, it is deemed undesirable and at best useless to those who are into good sound quality. There is nothing inherently evil about rear speakers, it's just that rear speakers often interfere too much with the ability of the front speakers to produce a believable sound stage and imaging characteristics. These effects can be minimized if care is taken to set up the rear speakers, but they are still there.

First, we discuss the "purist" view on rear speakers. Rear speakers grew out of necessity rather than the pursuit for better sound quality. A lot of cars, especially compacts and sub-compacts, have very small speaker openings in the front of the car due to space restrictions. It is rather rare to find a stock speaker location that can fit something as desirable as a 6.5 inch driver, while 4" and 4x6" speaker openings are quite popular. Small speakers are usually incapable of producing low bass (below 100Hz) at a satisfying level (say 90dB for casual listening.) Rear speaker mounting locations, especially the rear decks of sedans, offer a lot of area to mount a sizable driver, thus car manufactures rushed to mount large speakers in the rear to fill in the low bass region. This would have worked out if the stock stereos fed a low-pass filtered signal to the rear speakers so that they only produced the low bass frequencies, in which case those rear speakers would be called woofers or subwoofers. But no. Car manufactures didn't want to let all that volume go to waste so they fed the whole signal spectrum to the rear speakers. To make matters worse, the signal sent to the rear speakers is in stereo. The end result is that the center of the sound stage is somewhere to the far-right behind the driver and far-left behind the passenger. The instrument and vocal image floats all over the rear of the listener and shifts dramatically depending on the position of the listener's head. This is not how a live performance sounds.

For the reason discussed above, rear speakers of any configuration will interfere with the proper sound stage production and imaging of the front speakers. However, there are measures that can be taken to minimize the effect. The simplest thing to do is to turn down the rear speaker volume. Close your eyes, keep your head straight and adjust the front-rear fader control while you listen to a piece of music with strong central vocal content (check this with your home stereo or sit in the middle of the back seat with the rear volume turned all the way down.) First, turn the rear speaker volume all the way down, and then slowly turn it up until the vocal image starts to drift to the opposite side of the car. If you are sitting in the driver seat, listen for it to drift toward the passenger side and vice versa. This is the point where the rear speakers are still noticeable but it is not interfering too much with the proper operation of your front speakers.

[ChrisM]

Sound dampening your trunk lid? A nice and easy way to cover it up is thin hardboard cut to shape and carpeted and screwed on. Nice example is this Suburu I found while looking on another forum.

[Superinc_V6]

Nissan Merta Harness PN:707550/717550
Left to Right
Big Plug
White Soild: Front Left (+) speaker
White /Black: Front Left (-) speaker
Gray : Front Right (+) speaker
Gray/Black :Front Right (-) speaker
Blue: Power attenna , must connected for radio to work
Yellow : Power consant +12V
Orange : Dimmer , lower your interior dash lights, it will lower your H.U. brightness
Red : Accessories +12V
Black/White : Chassis ground , connected to both headunit and(if) parking brake signal is Required (video headunits)

Plug 2 small
Purple : Rear Right (+) speaker
Purple/Black: Rear Right (-) speaker
Green : Rear Left (+) speaker
Green/black:Rear Left (-) speaker
Black/White: Signal ground
Blue/White: Remote Amp turn-on

...

[nismos14]

Tuning a port:

4 types of tuning

A: 20-30 hz tuning is geared towards SQ

B: 31-35 hz tuning is geared towards SQL

C: 36 - 40 hz is on the brink of pure spl tuning but will typically yield decent sq with more spl.

D: 40hz + is generally for straight spl, and used with test tones going through the driver for competition purposes.

There are many good tuning calculators, some do NOT take into account sub displacement so be sure to calculate that.

Basic Car Audio Electronics has a good one located here:

The following links also helped me in choosing my port length.

Woofer Enclosures - Fraction to Decimal - Parallel - Series - Port Length and Volume Calculators

PORT Size Calculations and Formulas for WOOFER and Subwoofer BOXES (Scroll down on this site, there are two calculators)

There are also different types of ports

Slot ported, and round ports.

Slot ports tend to recduce the likelihood of port noise. They also tend to be larger boxes. Port tubes in an enclosure can be very finicky. It is a good idea to use aero ports with flared ends to avoid the issue of port noise.

With any Ported enclosure it is a very good idea to use subsonic filters at or SLIGHTLY below the tuning frequency. Here's an example of why.... Say you have a 500 watt amp pushing a sub in a box tuned to 35 hz. Any frequencies that go through the driver below 35 hz can cause the driver to unload because below the tuning frequency there is less resistance to the motion of the driver and quite a bit less power handling. It is essentially a free-air driver below the tuning frequency. Therefore, if the driver has a low QTS, it is likely that even if the driver is rated for 500 rms, the mechanical limits will change when it is below tuning frequencies. In some cases you may be able to get away with it. So basically, just like a driver that is being used IB it would loose some of its power handling if it is not specifically made for IB use. The driver's ability to handle the full 500 watts is no longer true below the tuning frequency and you could very well destroy the woofer in that scenario.

Ported enclosures do require extra care in design and build as a ported box that is not built properly for a specific driver may cause damage to it.

Ported boxes tend to be much more efficient than sealed enclosures although this may not ALWAYS be the case. Above the tuning frequency the driver will also tend to handle more power.

The length of the port is crucial in determining the proper freq. The longer the port area/volume the lower the tuning would be. For instance in my application I have a 1.88 cu ft box with a port that is 15 inches this gives me a tuning of ~32 hz. A shorter port woud have given me a higher tuning freq. If it was 10 inches the tuning frequency would rise into the high 30's.

[CAMSHAFT]

Active vs. Passive: An attempt by me to explain - Car Audio Forum - CarAudio.com

A very imformative thread from another Forum.

[Groggy23]

Found this on ECA, here is the original link: Elite Car Audio : Car Audio Forum - Tuning tutorial-cmusic, winslow, slick?

Basically this focuses on phase or switcing the polarity of each individual speaker. Should help with blending, staging and imaging to a certain extent.

"""
There are several different methods used to tune eqs. This is the one I use. An RTA is not needed if the steps are done correctly. This method uses crossovers and gain settings as the most important factor in tuning. I think the eq should be last in line when tuning. Remember after each step to write down your settings. If the sound gets worse, then you can go back to the previous step’s settings and start over.


1. Set all bands flat, as well as the head unit bass and treble.

2. Turn off the subs. Using music with a good bass line, run the highpass crossover up and down until the midbasses can play as low as possible without any distortion or excessive door panel vibrations.

3. Unhook the mids and tweeters, allowing only the midbasses to play. Listen to mono pink noise or a well-recorded song with a centered vocalist. Test CDs such as the IASCA test CD or Autosound 2000 Test CD 102 or 103 will work great. Listen to where the centered sounds are coming from. Then reverse the polarity of one midbass (Reverse the speaker wires coming from the passive crossover and going to the speaker, just flip the positive and negative wires. I usually flip the driver’s side speaker.) and re-listen to the test CD. If the sounds are more centered then keep it as is. If the centered sounds are more diffuse and un-locatable, then flip the polarity back to where it was originally.

4. Then unhook the midbasses and play the mids only and follow the same polarity and listening tests as before. Mark your best settings.

5. Do the same procedure for the tweeters.

6. When you have tested for the proper polarity from all three ranges of speakers, hook all of them back up with respect to each set of speaker’s best polarity. You can have any combination of polarity, such as all the midbass and tweeters straight and one midrange reversed.

7. Now you should have the correct “acoustic” polarity set within each set of speakers. Next is to set the acoustic polarity between the sets of speakers.

8. Listen to some very familiar music with a good range of sounds. Then flip both midbass’ polarity and listen again. Before you only flipped one midbass, now you are doing both at the same time. For example if the left midbass was reversed and the right was not before, now the left will be not reversed and the right will be. Listen to the music again. If the midbass is more powerful and full then leave the wiring as is. If the midbass sounds weaker and wrong then restore the wiring as before.

9. Perform the same listening tests while flipping the mids and tweeters, and use the wiring configuration that sounds the best.

10. If you have went though all these steps adjusting the polarity of the speakers then the system should sound really good without any eq adjustments. You might want to play with the gain adjustments on the crossover and/or amp to better blend all the speakers together.

11. Now onto the eq! The first eq step is to adjust the tonality. While listening to familiar music, adjust each individual band up and down slowly. When the music sounds better then move to the next band. Adjust the left and right bands equally. (We’ll get to the separate left and right adjustments soon.) It really does not matter if the bands are boosted or cut, just that it makes the sound better. Not every band needs to be adjusted. In fact if you did steps 1 thru 10 correctly you should not have to adjust over half the bands. Having a 1/3 octave eq does not mean you have to adjust every band. It means you have the ability to adjust each band if needed. Watch out for big jumps from band to band, like one band set to +4 and the next band set to –6.

12. Continue through all the bands, take a break, and do the same procedure over again. But this time the adjustments will be smaller as you get the tonality dialed in. This step might take several days, weeks, or longer.

13. In tuning you will find some eq bands will raise, lower, move the sound closer, or farther away if adjusted in certain manners. For example, lowering 5 KHz will generally move the soundstage farther away and raising 2 KHz will make the soundstage rise. Each vehicle and system will have different settings that will be the best. The best way to achieve awesome sound is to constantly adjust.

14. When you are satisfied with the tonality of the system, it is time to start adjusting the left and right channels separately. These adjustments should not affect the tonality, but improve on the imaging and soundstaging. Using the Autosound 2000 Test CD 102 or 103 “My Disk” listen to the individual frequency pink noise tracks. (Test CD103 has the tracks arranged in an easier configuration.) Each frequency band should sound like it is coming from the center of the soundstage. If one band is off to one side, then use each band’s left and right eq controls as a balance control. This is very similar to the head unit’s balance control, only now you are balancing each frequency band by itself. For example if 200 Hz seems to be shifted to the left of center, lower the left 200 Hz band and raise the right 200 Hz band one dB at a time until the band is centered. If a frequency is shifted to the right, lower the band’s right channel and raise the left channel in small amounts.

15. When you have when through all the bands take a break. Then later go back through each band one by one and make any further needed adjustments until all the frequencies are lined up in the center of the soundstage.
"""