One of the greatest tools in the audiophile toolbox is math. What? Math sucks you say. Well I say get your calculators out and start working your brain. This will be fun, honest.
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.
When discussing Q-Logic Q-Forms or Q-Customs, often I get the same question- Why Plastic? With all of the different types of materials available, why use plastic, why not wood or fiberglass? There are several answers to this question, and I will get to all of them.
Wood- Wood is great for the basic flat enclosure. It is cheap, dense, rigid and easy to work with, which is why it is the single most common type of material used for subwoofer enclosures. The problem with wood is that it is hard to bend. It can be bent and molded to a point, but mimicking the shapes of a car is way beyond what regular wood is capable of.
Fiberglass- This stuff is awesome. It can be formed to any shape, it’s strong as hell, super lightweight and costs a fortune. Oh wait, that is not a good thing. The price of fiberglass resin is expensive, and it keeps going up. Five years ago, the price for a gallon of resin was around $30, now it closer to $60. Considering that you can easily use 2 or 3 gallons in even a small two-10” sub enclosure or a gallon of resin for a pair of kickpanels means that the project becomes very expensive. While fiberglass is very strong and resists flexing (to the point that it just breaks), building tooling molds for fiberglass is more expensive than the materials to make the part. The molds must be two or more parts and it takes around a day to make a single set of parts from one mold, depending on the size of the part. This makes it cost prohibitive for use in our type of manufacturing. Sure, building a show car with fiberglass molds is not a big deal, you are only going pull a few parts from each mold and you have bigger budget, but for mass-production, it simply is not worth it.
There are several different types of plastics that are used for manufacturing. I am going to touch on the three most common types.
Innovation in car audio is difficult. Whether you are talking about unique materials or custom equipment, being innovative is not a simple task. Just about everything has been done before, but that does not mean that it can’t be done better. Q-Logic has been in the business of building pre-fabricated enclosures and vehicle-specific kickpanels and enclosures for 20 years. I bring this up because up until recently, Q-Logic has been manufacturing all kickpanels in .140” thick plastic, which is just over 1/8” thick. This makes for fairly strong component and has been good for many projects. That said, one of the biggest complaints about the kickpanels has long been that the plastic has a high resonant frequency, meaning that they can buzz during certain passages in the music. A common fix for this is lining the back of the panel with Dynamat, which is always a good idea. Since Q-Logic is making a comeback, it was important that a few changes be made. One of which is thicker plastic. All Q-Forms are now formed from .180” plastic.
Not only does this make the panels harder to deform and install incorrectly, but it also lowers the resonant frequency. With more mass and inherent rigidity, the panels feel better in your hand and fit better in the car. This plastic has been retrofitted to work with all of the previous tooling and all new designs are being done to accommodate the thicker plastic.
Being innovative does not mean using something completely new, sometimes it just means better.
Why I hate the iPod
I grew up using Apple computers. In 1985, when the Mac came out, my parents bought one. I loved the Mac, even though all of the games I wanted to play were IBM-based. So when the iPod came out you would think I would love it, right? Incorrect-amundo my friends, I hated it. I called it back in 2001, when it hit the market- iPod will kill the car audio industry. Flash forward to 2008, the car audio industry as a whole held a 12-volt summit to discuss what the hell happened to car audio. I was there and when that mic was passed around, I was the first to grab it and I proclaimed “It’s all our own damn fault!”
There were MP3 players before 2001. I had one, it was a Creative Labs Nomad HDD player. It was cool, I didn’t have to worry about skipping or scratched CDs, but I didn’t use it in the car. I had a competition system and I was not going to play crappy MP3s through it. That is paramount to buying a Formula 1 car and trying to tow a trailer with it, it just doesn’t make sense. I knew it was all over the day I saw Alpine come out with an iPod adapter for your car- the industry killed itself in one fell swoop, giving up its precious market share to a $200 device. Now iPods are a billion dollar industry by themselves. That used to be car audio money.
The problem is that the industry saw the iPod as the next big thing, which it was, but we lost sight of what built this industry- good audio, not integration of an iPod. When you plug an iPod (iPods in particular) to a car audio system, it is the equivalent of playing a tape through an FM radio station. You are taking compressed audio (even if you use FLAC or other lossless codecs), playing it through a small device that was designed to output to .25” ear bud speakers into the radio. iPods castrate music. The software in the unit cuts out the low frequencies so that the earbuds don’t pop. This kills bass output when you plug it into your car.
When I listen to my Samsung P2 while mowing the lawn, exercising or whatever, I use Skull Candy full-size headphones with the built-in bass shakers. This emulates the feeling of bass frequency output. I really like the headphones. Occasionally I will plug my P2 into the wife’s minivan while on a road trip, the stereo is bone stock and sounds like crap anyway. Plug an iPod into a high-end car audio system and you quickly become aware of the differences. Try this- play a song through you iPod and then play the same song through a real CD (not a burned MP3) the difference will likely amaze you, even on a stock system.
While every system uses different components, there is one area that is often overlooked, the wiring. I am not talking about the power and ground wire that runs to the amps or the speaker wires, I am referring to the charging system. Before adding anything else, upgrading these wires is critical for optimum performance. Most enthusiasts call it the “Big Three”, and it will do wonders for your system’s performance.
The big three refers to the wiring for the charging system; battery to ground (frame or body), alternator to battery, and engine to frame (or body). Contrary to popular belief, electricity flows from negative to positive, not the other way around. The negative cable is just as important as the positive cable; the methodology of transferring that power is just different. Most cars use negative ground systems, and all car audio equipment is designed for negative ground systems. This is where the negative pole of the battery ties to the vehicle’s metal body or frame. The positive pole of the battery is run to each component with individual wires, so each component gets the proper gauge of wire it needs for the length of run and current demands. The negative pole is supplied by the entire chassis of the vehicle, ensuring that the chassis has the best supply feed is critical.
Starting with the battery negative pole to chassis, pull the original wire and replace it with at least 4-gauge wire. It is a good idea to match the amplifier power feed cable gauge, if not use a bigger cable. In my cars, I use 1-ga battery to frame cable. You should clean the frame (or body if a unibody car) where the battery ground attaches. This should be secured with a bolt and not a screw. Any paint, rust, scale or grease should be cleaned away as well, you want a nice clean metal only surface. If the factory location does not allow you to use a bolt, move it. It does not have to be in the same location as the factory cable, but it should be as short as possible. You don’t want a 4-foot ground cable if you can help it, as the shorter the cable, the less resistance you will have.
2009 Mid-America Ford and Shelby Nationals
This year marked the 35th annual Mid-America Ford and Shelby Nationals event held at several locations in Tulsa, OK area. The 5-day long event included road racing at Hallett Motor Circuit, drag racing at Tulsa Raceway Park and a car show at the Southern Hills Marriott in Tulsa, OK. This was my third year covering the event, and it was also the best so far.
When I arrived on Wednesday morning, the Shelby Automobiles booth was set up and ready for business. This being the media day, they had several Shelby cars ready to be put to the test on the track by the journalists. I patiently awaited my turn to get behind the wheel of a Shelby, and finally that moment came. They said “Jefferson, why don’t you take out the Terlingua”. I obliged, thinking this would be fun.
The Terlingua Shelby is an aftermarket package assembled by Shelby Automobiles. Basically, you purchase a new 2010 V6 Mustang (yeah, I said V6) and the folks at Shelby bolt on a Paxton supercharger, 6-piston brakes, a new hood, Ford Racing suspension and add the Terlingua graphics kit. The Terlingua Mustang is a continuation of the famed Terlingua Racing Team formed by Shelby in the 1960s to compete in Trans-Am racing. The new version is as race inspired as you can imagine. The car handles incredible, and the Baer brakes will throw you through the windshield. The supercharged V6 has plenty of power, putting out more than the stock 4.6 V8 found in a Mustang GT. If you want a car that will haul ass and take corners like an F1 car, this is it.
The next car I drove I will remember forever. Shelby had brought out a couple of continuation cars, cars that are built just like they were when they were new, a Shelby Daytona coupe and a GT40. While I did not get a chance to drive the GT40, the Daytona was the highlight of the day. This is a full-on race car. Race pedals, mid-engine 427 big block, race tires, harnesses, the whole deal. The interior literally wraps around you, if you are big person (at 6’ I barely fit with a helmet on) it is a little claustrophobic. Oh well, cause when you drop the hammer going around a blind up-hill right-hand turn and the car side-steps a bit then digs in and launches you down the straight-a-way, none of that matters. It was too much fun.
I finished the day driving the new 2010 Shelby Super Snake. This 725 hp machine puts so much power to the ground, triple digit speeds are commonplace on short straight runs on the track, given the opportunity on the street, and this car would be scary fast. Taking hairpins at 60 mph is not a problem with the race-tuned suspension of the Super Snake. While the package may be a little pricey ($33,495 for the 725-hp post-title package version, that’s in addition to the $47k Shelby GT500 price tag) you couldn’t build the same performance in the same car for less.
If you ever have the opportunity to visit the Mid-America Ford and Shelby meet, do it. It will be something you never forget.
The US government as well as many state governments have been trying for years to get rid of us. We are the automotive hobbyists. Whether it is suspension limits (lifting or lowering), noise ordinances or emissions restrictions, they just don’t like us or some reason. The latest attempt is a doozy.
The US congress has introduced a bill that will put in place a national vehicle scrappage plan in an attempt to boost domestic auto sales. The plan states that you can take any car that you have owned for one year (and had insurance on) to any car dealership and get a voucher for $3500 to $4500 toward the purchase of a new car that gets better gas mileage. I won’t go into the dirty details, but you can find it on USA TODAY.
The Specialty Equipment Manufacturers Association (SEMA) has been fighting this legislation, knowing full well that with the full weight and support of the President of the United States, they didn’t have much hope of killing it. These programs threaten the very livelihood of the automotive aftermarket industry, as many of the cars that would be scrapped tend to be older cars that don’t get driven, and do not contribute to pollution, but are a much needed resource for parts and projects. In an impressive win, SEMA has managed to get a 25-year exemption worded into the bill. This makes it so that the car must be 1984 or newer to qualify. Not many classics in that time period.
What makes a Car Audio system sound good? Questions answered by renowned audio engineer, Joe Gross of Q Logic
Since 1988, Q-logic has been providing vehicle-specific subwoofer enclosures, replacement kickpanels and pre-fabricated universal subwoofer enclosures for car audio enthusiasts. Originally started in the back room of a local car audio shop in Stillwater, Ok, owners Dave Cunningham and Bill Basore knew they had something special. By the mid-Nineties, Q-Logic had grown to be a household name in the realm of car audio, every major shop in the country sold Q-Logic brand subwoofer enclosures and the full line of Q-Forms and Q-Customs.
Q-Logic eventually grew to be so big that the big boys, namely Rockford Fosgate, noticed. During a time span where Rockford was gobbling up brands like MB Quart and Lightning Audio, they bought the Q-Logic facilities in Stillwater, OK. During that time, the Stillwater plant was used to build Rockford Fosgate enclosures as well as Q-Logic brand products. Big business politics and short sightedness lead to a decrease in Q-Logic market penetration, since the Rockford sales reps were now Q-Logic reps too. Selling empty wood boxes and plastic kickpanels is different than selling ten-thousand dollars worth of amps, subs and speakers. Q-logic became an “alsoand”, and did not get the attention it deserved. Read the rest of this entry »