When it comes to the automotive hobbyist industry as a whole, encompassing everything from rodders and tuners to restorations and show cars, there is a lot of animosity on the inside. Cruise a muscle car through a group of old-school hot rodders or tuner cars and you will get griped at. Don’t even think about trying to park a Honda between to a ’69 Camaro and ’71 Challenger, it might not be drivable when you come back. But is it necessary? Of course, it isn’t, but this is the difference between fans and fanatics.

Back in the early ‘90s, when I got my start in car audio, things were a little more crazy than they are these days. If you had Rockford Fosgate, Alpine or Phoenix Gold gear, you hung out with guys that had the same gear. You certainly didn’t mix and match your gear. Today, everything is jumbled up and there is a lot less hatin’ going on in the parking lot.

Most of the time, I would say that being a fanatic is a bad thing. Religious fanatics, political fanatics, they really just cause trouble for the rest of us normals. Being a car audio fanatic doesn’t hurt anybody, as a matter of fact, it is actually helpful. Being a car audio fanatic means buying more gear. Spreading the word about building better car audio systems, impromptu sound-offs in parking lots and at stoplights. Being a car audio fanatic is more than just dropping some subs in your trunk, it is a lifestyle, one that you have to be proud of and display to everyone.

I am not saying that you should cruise around neighborhoods at 11pm with the bass booming, waking everyone within 3 miles, that just give the rest of us a bad name. Instead, take it to the high-school parking lot, the cruise nights and the football games. Find a car audio competition and enter. Get involved and show them that you are true fanatic. Oh, and toss that iPod and buy some real CDs, they sound better (had to say it!)

While it may seem like shameless self-promotion (which it is), my latest book, “How to Design and Install In-Car Entertainment Systems” is finally on the shelves. After months of hard work, late nights and several purpose-built systems, the book is done and on the boat from China. Yeah, they print them in China. Don’t worry, I am sure the paper is lead-free, at least I hope it is.

In case you are wondering, the book covers everything car-audio and then some. The first chapter is all about the fundamentals of car audio and electronics, which is to say a brief primer on automotive acoustics and basic electrical theory. It is presented in a way that is easy to read and understand, so you don’t get bogged down in the mire of technical jargon. The next two chapters are about planning and basic installation tools and techniques.

From there the book gets into the nitty gritty details of installation. Covering all the basics like head units, amps, subs and speakers to MP3 players and GPS. Many of the techniques shown in the book are cutting edge, things you won’t find ANYWHERE else. These are the tips and tricks that make installing car audio much simpler for the novice and may even provide the pro with a few ideas too.

Want to know how to blend a TV into the dash of your ride? It’s in here.

Always wanted to understand how cancellation and reflective waves work inside a car? Read it here.

Need some guidance for GPS navagation systems? Find your answers in the book.

If you are a beginner in car audio, spending $26 bucks on this book can save you hundreds in mistakes and installation costs. You need this book.

Drop us a line if you want one. We will be selling a few through the site as soon as we get our grubby little hands on them.

As my family and I are headed to Detroit for the Woodward Dream Cruise, we are discovering the fantastic level of technology loaded in this car. Chrysler lent me the vehicle specifically for this trip, to get an idea of what Chrysler has to offer. I have to say, it is impressive to say the least.

Starting with the 4.0 liter V6 and 6-speed automatic, this minivan hauls. I am certainly not going to sit here and tell you that a minivan is super quick, nimble or any of that, but when you tell it to go, it growls back and pushes down the road. We had no trouble passing on the highway, doing well over the posted limits (I may be driving a minivan, but I am still a gearhead). The best thing about it is that the exhaust is whisper quiet until you floor, it actually sounds like a car with some balls, and it likes showing them. Full-throttle blasts down the interstate are met with ease, the van does not sound like it is straining. For a minivan, its pretty fun.

Features and amenities are quite lavish in the SXT. Dual sliding power rear doors, power hatch, sunroof, and the rear side windows roll down. The Stow-N-Go seating is really nice, a push of a button and the rear seats lay down flat. Dual A\C controls for the front passengers and rear A\C for the back makes trips easier. I like it blasting full cold, but my wife and kids do not, so I don’t have to fight with them over that.

All of these features are nice but where this thing really shines is in the entertainment features. Holy crap this van has it all. Dual (as in two) rear dvd 9” fold-down screens with IR headphones, one for the middle and one for the rear seating. The system is controlled via the remote or the Uconnect DVD screen head unit in the dash. The head unit has full Bluetooth connectivity, with navigation and a built-in hard drive for all your music. An iPod connector in the glovebox lets you go direct (if you are into that whole iPod fad). Sirius\XM satellite radio is included.

Sounds good right?– we are only getting started. The two rear TVs are wired to the Sirius TV system. My kids are watching Spongebob on Nickelodeon while the wife and I are listening to some music we loaded to the hard drive. Actual TV streaming into the car without a big ugly antenna on the roof, it is all coming through the Sirius TV antenna, which is hidden under the roof. Once my kids discovered the live TV, they were spoiled forever. Going back to my 2008 Chevy Uplander is not going to be easy.

I have saved the coolest piece of technology for last. Upon receiving the Grand Caravan, I noticed a black box with two antennas. Further inspection proved correct, this sucker is loaded with the latest in Mopar features, the AutoNet mobile WiFi system. Utilizing the nationwide 3G cellular network, the AutoNet system provides the occupants with full internet capability anywhere in the US. Not sure where your hotel is? Type it and get the address. Send email, surf the web, post to your blog all from the comfort of the heated leather seats of the most technologically advanced minivan in the world.  The fact that I am posting this while cruising up Route 66 on our way to our first stop, St. Louis, is pretty damn cool.

In retail, chat forums and lunch rooms across the country the single most common questions are “how do I get my system louder” or “how loud will these subs be”. I can personally guarantee you that you ask ten people this question, including the guys at the stereo shop, you will get 13 different answers and none of them will be basing their answers on facts. They simply do not know how it works. There are some basic physics at work here.

Volume, which is measured in decibels (expressed by dB), is a function of power, cone area, enclosure design, and transfer function. Oh, you knew that already? Ok, sure that last statement might seem a little obvious, but undestanding how they interact togethr is critical to calculating volume. That’s right, you can calculate exactly how loud you system will be. Enough BS, here is the worksheet. You won’t find this anywhere else, send your friends.

This formula requires a few specs. First, you need the sensitivity of the sub(s). This listed on the woofer spec sheet in dB. It is sometimes notated as the SPL of the sub. Next, you need to know how much power your amp puts out. An amp birth-sheet (usually included in the box) will have the actual power the amp displayed when it was tested at the factory. Not all amps come with these. If you do not have such a sheet, you can use the power ratings, or even better, you can test it yourself (that is whole other enchilada and we will get into that another time). Other specs you need are more simple- what type of car do you have- truck, hatchback, or sedan; and what kind of box is it installed in. The enclosure will make a big difference, if it is a crappy home-built box with lots of leaks, held together with carpet and liquid nails, it probably won’t function as well as a professionally-built enclosure (like the Q-Logic pre-fab enclosures- shameless plug) and how many woofers you have. Have fun.

Sensitivity =

Every time the cone area doubles, the output of the system increases by 3 dB, which is relative to a doubling of volume. If you have 4 subs, you would add 9 dB to the sensitivity rating of the subwoofers.

add 3 dB per doubling of cone area

i.e. 2 subs, 3 dB, 4 subs, 6 dB

Let’s consider sub sensitivity, with 3 dB per sub added and calculate the SPL. Each time the output power (wattage) of the amplifier doubles, the SPL increases by 3 dB. To figure this, use the following figures.

This represent 3 dB added per doubling of power starting at 1 watt/meter SPL.

1=0

2=3

4=6

8=9

16=12

32=15

64=18

128=21

256=24

512=27

1024=30

2048=33

4096=36

8192=39

Next we add in Transfer Function

add 12 dB for a standard car/truck

add 16 dB for a hatchback car

Now we figure in box type

For a sealed box, 0 dB, sealed offers no dB gain.

For a ported box, 3-9 dB depending on tuning frequency and air ripple. The higher the ripple, the more gain but at a cost of sound quality.

For a bandpass box, 6-12 dB again depending on the tune freq. and ripple.

For example, a 12″ Rockford Fosgate subwoofer has a sensitivity of 86 db at 1 watt/1 meter, and is capable of handling 300 watts.The sub is installed in a ported enclosure, so we are going to use a the lower output rate for the ported box at 3 dB. Powering the subwoofer is a Rockford Fosgate Punch 300-1, which is rated at 300 watts to a single 4-ohm load. All of this is installed in a 2006 Honda Civic Si, which is a hatchback and gets a boost from the 16 dB transfer function. Using the formula, we get the following results-

86+ 24 (at 256 watts, it is close, but you could add in an extra dB if you want) + 16 (trans function) + 3 (box gain) = 129 dB estimated output. This estimation will be within +\- 3 dB of the measured output. This is simple physics, and it works.