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Subject: rec.audio.car FAQ (Part 5/5)
This article was archived around: Tue, 9 Aug 2005 06:30:44 +0000 (UTC)
Last-modified: 08 August 2005
This section describes the competition branch of the car audio world -
what it is, and how to get involved.
6.1 What is IASCA, and how do I get involved? [JSC, HK, IDB]
IASCA is the International Auto Sound Challenge Association, a
sanctioning body for car audio competitions held throughout the world.
Competitors earn points at each competition, and those that perform the
best each year can advance to the finals. Prizes (trophies, ribbons,
and sometimes cash) are usually given out to the top competitors in
each class at every competition.
IASCA memberships can be purchased at your local car audio retailer, if
they are an IASCA member. You can call IASCA at 602/437-4678 to get a
list of IASCA shops in your area.
6.2 What is USAC, and how do I get involved? [HK]
USAC is another sanctioning body, similar to IASCA. However, USAC
places greater emphasis on SPL measurements than IASCA.
6.3 What are the competitions like? [HK, CD, IDB]
They are much like loud car shows: a lot of cars parked with their
hoods/doors/trunks open showing their audio systems. There are two
types of judging styles: 1) drive through - where competitors drive
their own vehicles to judging stations to be judged, and 2)
walk-arounds - where the teams of judges will walk around the event
site and judge vehicles that fit within their judging assignments.
Typically SPL is done first with the mic stand in the driver's seat and
the competitor in the passenger side adjusting only the volume.
Hearing protection must be worn. After SPL measurements are completed,
RTA measurements are performed by playing pink noise. When the volume
level is within the specified "window" around 90db-110db, the RTA judge
will signal you out, and at that point you must exit the vehicle for
the actual scoring measurements. The next area for judging should be
sound quality where two judges will sit in your car and judge the sound
quality based on IASCA's reference CD/tape. The next area is
installation judging where the competitor has 5 minutes to explain and
show the installation of his/her vehicle. It is very useful to have a
picture book/album of photos of the installation that may not be
visible to prove that items not visible do exist. When that is
completed, the competitor can park the vehicle and show spectators the
vehicle. These procedures may differ from show to show, and at the
regional/final levels they are very strict in what can and can't be
done, e.g. a judge will make sure no adjustments are made after SPL
until after sound quality judging is over, ear protection, etc.
Most involve a lot of waiting around. Thus, they are perfect for
meeting other people interested in car audio, and seeing some
installations which may give you some ideas. They're also perfect for
listening to some cars that sound a lot better and a lot worse than
your own. In IASCA competition, the cars are judged on:
* Installation Quality (187 pts possible)
- Wiring (40 pts)
- Source Units (15 pts)
- Amplifiers (25 pts)
- Speakers (25 pts)
- Other Devices (25 pts)
- Overall Creativity (30 pts)
- Attention to Show Details (20 pts)
- Security and Convenience Features (7 pts)
* Sound Quality (248 pts possible)
- Tonal Accuracy and Spectral Balance (100 pts)
- Soundstage and Ambiance (65 pts)
- Imaging (50 pts)
- Sound Linearity (30 pts)
- Ergonomics (+/- 3 pts)
- Noise Adjustment (up to -20 pts)
* Frequency Response - RTA (40 pts maximum)
* Sound Pressure Level - SPL (1 point per dB)
6.4 Should I compete? [CD]
You should compete if:
a. You have an okay sounding stereo
b. You have an okay installation (i.e. no amps/changers sliding
around in the trunk)
c. You'd like some pros to comment on your system
d. Your feelings won't get hurt if you don't get first place
e. You've been to a contest and talked to competitors about it
f. You've read the rule book
g. You've listened to a test disc in your car, and understand
what the sound quality judges are listening for
You can compete even if you don't do all of the above, but the
recommendations will help you understand and gain the most from
6.5 What class am I in? [HK, JSC]
This section is mainly geared toward IASCA.
There are three classes: novice, amateur, and pro. The novice class is
intended to be an unintimidating level where beginners can start out;
however, a competitor may only be in the novice class for one year, at
which time he is automatically moved to the amateur class. Most
competitors stay in the amateur class indefinitely, unless they become
affiliated with a car audio shop or manufacturer, at which point they
are moved into the pro class.
Are you or were you employed by a car audio manufacturer or dealer?
You compete in pro
Is this your first year of competing?
You compete in novice for the first year
You compete in amateur
Note that modifying your amplifiers, buying your equipment below
retail, or being sponsored by a manufacturer or dealer will get you
kicked into pro.
Also note that any home built active gear in the signal path (e.g.
custom built equalizers, crossovers, or noise gates) will get you
kicked out of novice.
Once you know what group you are, you next need to know what power
category you are in. Add up the 4-ohm non-bridged rating of all your
amplifiers, including your head unit if your head unit is powering
speakers (rather than exclusively feeding amplifiers). Then, find the
category you fit into:
Novice 1-150 151-300 301-600 601+
Amateur 1-150 151-300 301-600 601+
Pro 1-150 151-300 301-600 601+
Expert 1-600 601+
Thus, if you had a Rockford Punch 4040 (20Wx4) and a Punch 60ix
(30Wx2), with a head unit that put out 6Wx2 (powering, perhaps, a
center channel) you're in the 151-300 class. It does not matter if
your amps are bridged down to .002 ohms; it's only the 4ohm rating that
counts. If you no longer used your head unit to power speakers, you
would be in the 1-150 class.
Competition is usually most vicious in the 151-300 and 301-600
categories at typical contests.
6.6 Where can I find out when these Sound-Offs are? [IDB]
The best way to get the most current list is to call either of the
sanctioning bodies (IASCA or USAC). They can be reached at
602/437-4678 or 601/939-7828, respectively. You can also visit the
Official IASCA and USAC pages on the web at the following URLs:
IASCA - `http://www.iasca.com'
USAC - `http://www.soundoff.org'
6.7 How do I get sponsored by a manufacturer? [CM]
Ah, the green grass on the other side of the competitor's fence;
sponsorship. Sponsorship is not the easiest thing to obtain. And it
might cause more problems than you anticipated. Obtaining sponsorship
really depends on how much dedication you show for competing and finding
the right manufacturer sponsorship deal at the right time.
Keep in mind that car audio manufacturers consider sponsorship a form of
advertising. Each manufacturer has a different policy concerning
sponsorship. They are looking for a competitor that has shown they are
committed to competing for a long time. They want someone that has
shown that they know how to win, but also, how to handle defeat
gracefully. They want someone that is well known in competition
circles, someone that new competitors can come to and ask questions
about the system and the manufacturer's products. They are basically
looking for people that will put their product out there for people to
see and help sell the equipment.
As a competitor, you must show that you are committed by to going to as
many shows as possible. You must open up your their vehicle and show
off the system. Manufacturers want a show system, which often means
turning your vehicle into a "trailer queen." That may require you to
buy a trailer and tow the vehicle to the shows you compete in (this also
means that you may need a new daily driver). And of course, if your
bought equipment below retail or were given the equipment, then you will
be forced to compete in the Pro or Expert class.
There are different levels of sponsorship. It usually starts with
manufacturer technical support. The manufacturer will give direct
technical assistance to the competitor. At larger shows, they may
reserve a space for you in their "tweek and tune" area.
Next, the manufacturers may let you buy equipment from one of their
dealers or the factory and a discounted price. This will definitely put
you into the Pro or Expert class. Some manufacturers will let you mix
and match equipment from different manufactures. Others want you to use
their equipment only.
Then the manufacturer might start giving you equipment and providing
some or all of the installation costs.
The holy grail of sponsorship is when the manufacturer provides the
equipment, installation, and pays some or all of your competition
expenses. It takes a lot of money to travel to shows. By the time
someone reaches this level, they are frequently hired as an employee of
the manufacturer. This is a good way of making the car audio business
This section describes various literature which you can read to brush
up on your car audio skills, or to keep current, or to see other
people's installations, or whatever else you'd like.
7.1 What magazines are good for car audio enthusiasts? [JSC,
MI, NML, JR]
Car Audio and Electronics $19.95/year
P.O. Box 50267 (12 issues)
Boulder, CO 80323-0267 800/243-6400
Car Stereo Review $17.94/year
P.O. Box 57316 (6 issues)
Boulder, CO 80323-7316 303/447-9330
Auto Sound and Security $28.95/year
P.O. Box 70015 (12 issues)
Anaheim, CA 92825-0015 714/572-2255
Car Sound Buyer's Guide $17.95/year
939 Port Washington Blvd. (Quarterly)
Port Washington, NY 11050 516/944-5940
Car Hi-Fi #23.60/year
Freepost (8 issues)
TK660 081 943 5943
Leicester KE87 4AW
Bilstereo Forlags AB Skr ??
Box 230 84 (? Issues)
104 35 Stockholm 08-34 29 70
7.2 Are there any newsletters I can read? [IDB]
Unfortunately, AutoSound 2000 Tech Briefs is no longer in publication,
and as a result, there are no more newsletters currently in publication.
7.3 What books can I read? [JSC, JW, TT]
_Loudspeaker Design Cookbook_
by Vance Dickason
Published by Audio Amateur Press
_Designing, Building and Testing Your Own Speaker System_
by David Weems
Published by McGraw Hill
_Killer Car Stereo on a Budget_
by Daniel L. Ferguson
Published by Audio Amateur Press
_The Car Stereo Cookbook_
by Mark Rumreich
Published by McGraw-Hill
7.4 Can I contact any manufacturers on-line? [IDB]
Yes, there are a number of manufacturers who have started to use the
Internet and can offer advice for component selection, installation and
advice. A list of these manufacturers is available on the WWW, at the
Here is a list of many of the people that have helped to build this
document. Many others (not mentioned here) have also made small
contributions, pointed out errors, or have provided moral support.
[JSC] Jeffrey S. Curtis <email@example.com>
[JLD] Jason Lee Davis <firstname.lastname@example.org>
[MI] Matt Ion <email@example.com>
[JW] Jerry Williamson <firstname.lastname@example.org>
[CD] Cal Demaine <email@example.com>
[MO] Mark Obsniuk <Mark_Obsniuk@sfu.ca>
[HK] Harry Kimura <firstname.lastname@example.org>
[RDP] Dick Pierce <DPierce@world.std.com>
[BG] Brian Gentry <email@example.com>
[JM] Jeff Meyers <firstname.lastname@example.org>
[MH] Marvin Herbold <email@example.com>
[TT] Trevor Tompkins <firstname.lastname@example.org>
[MM] Matthew E. Meiser <email@example.com>
[NML] N. M. Lines <firstname.lastname@example.org>
[IDB] Ian D. Bjorhovde <email@example.com>
[JG] John Graley <firstname.lastname@example.org>
[DK] Dan Kreft <email@example.com>
[JR] Jason A. Reiser <firstname.lastname@example.org>
[PW] P. Wilson <scratchy.mi.net!ccbbs!pwilson>
[JGr] Jerry Grooms <email@example.com>
[PK] P. Kaufmann <firstname.lastname@example.org>
[MS] Manville Smith <email@example.com>
[LC] Ligeng Cao <firstname.lastname@example.org>
[AO] Andrew C. Ohnstad <email@example.com>
[MB] Michael Brennan <M1Brennan@aol.com>
[RK] Russell Kinder <firstname.lastname@example.org>
[MHa] Mike Harmon <email@example.com>
[ST] Steven Tolleneer <Steven.Tolleneer@ping.be>
[JD] John Durbin <firstname.lastname@example.org>
[PO] Paul Ozello <email@example.com>
[PS] Phil E. Salisbury <firstname.lastname@example.org>
[CM] Chuck Music <email@example.com>
[BW] Brian Waplington <firstname.lastname@example.org>
[AK] Andrew Krause <email@example.com>
[MZ] Mark Zarella <firstname.lastname@example.org>
Note: Many of these email addresses may be out of date.
This section keeps a running log of the changes to this document.
+ $Log: rac-faq.texi,v $
+ Revision 4.55 2005/08/09 05:59:45 ianbjor
+ Added new acronyms.
+ (see Section 1.1)
+ Revision 4.54 2004/03/06 06:09:41 ianbjor
+ Rewrote and expanded section on stiffening capacitors.
+ (see Section 2.9).
+ Rewrote section on battery upgrades.
+ (see Section 2.10).
+ Rewrote section on using MP3 files in the car.
+ (see Section 3.32).
+ Revision 4.53 2001/06/04 02:10:05 ianbjor
+ Fixed title of section.
+ (see Section 2.10).
+ Revision 4.52 2000/02/09 00:53:29 ianbjor
+ Updated for February 2000 Distribution
+ Revision 4.51 1999/12/06 06:08:32 ianbjor
+ Updated for December 1999 distribution.
+ Revision 4.50 1999/11/06 20:21:33 ianbjor
+ Added section on creating mono signals.
+ (see Section 5.16).
+ Updated for November 1999 distribution.
+ Revision 4.49 1999/10/04 08:19:20 ianbjor
+ Added _The Car Stereo Cookbook_ to the Books section.
+ (see Section 7.3).
+ Added section about playing MP3 files in the car.
+ (see Section 3.32).
+ Updated for October 1999 distribution.
+ Revision 4.48 1999/08/30 03:57:46 ianbjor
+ More updates to URLs.
+ Revision 4.47 1999/08/30 03:50:23 ianbjor
+ Added section regarding Alternator vs. Battery vs. Capacitors.
+ (see Section 2.10).
+ Updated for September 1999 distribution.
+ Revision 4.46 1999/08/30 03:38:00 ianbjor
+ Fixed various typos.
+ Updated section about turn-off thump.
+ (see Section 2.2).
+ Revision 4.45 1999/08/30 03:00:10 ianbjor
+ Added section regarding manufacturer sponsorship.
+ (see Section 6.7).
+ Revision 4.44 1999/08/29 20:59:55 ianbjor
+ Updates to various URLs throughout the document.
+ Revision 4.43 1998/12/07 17:59:17 ianbjor
+ Updated for December 1998 distribution.
+ Revision 4.42 1998/11/09 14:12:23 ianbjor
+ Updated for November 1998 distribution.
+ Revision 4.41 1998/09/08 08:19:30 ianbjor
+ Updated for September 1998 distribution.
+ Revision 4.40 1998/07/07 16:29:01 ianbjor
+ Updated for July 1998 distribution.
+ Revision 4.39 1998/07/07 16:15:14 ianbjor
+ Added section about determining subwoofer enclosure dimensions.
+ (see Section 4.13).
+ Revision 4.38 1998/07/07 16:00:59 ianbjor
+ Added Special Requirements for working with Plexiglas.
+ (see Section 5.24).
+ Revision 4.37 1998/07/07 15:58:09 ianbjor
+ Added section about tools used for cutting Plexiglas.
+ (see Section 5.23).
+ Revision 4.36 1998/07/07 06:06:23 ianbjor
+ Add sections about MDF.
+ (see Section 4.6).
+ Revision 4.35 1998/07/07 05:45:02 ianbjor
+ Clarified static shock section.
+ (see Section 2.7).
+ Revision 4.34 1998/07/07 05:39:33 ianbjor
+ Added section about using an aftermarket changer with the
+ stock head unit.
+ (see Section 3.25).
+ Added reference to this new section to the options for
+ using a stock head unit.
+ (see Section 3.24).
+ Revision 4.33 1998/05/13 06:56:34 ianbjor
+ Updated for May 1998 distribution.
+ Revision 4.32 1998/05/13 06:47:28 ianbjor
+ Updated totals for IASCA scoresheets to use current (1998) scores.
+ (see Section 6.3).
+ Revision 4.31 1998/05/13 06:39:40 ianbjor
+ Added information about turn off thump, and how to get rid of it.
+ (see Section 2.2).
+ Revision 4.30 1998/05/13 06:22:15 ianbjor
+ Added section about Magnet Size.
+ (see Section 4.12).
+ Revision 4.29 1998/04/10 07:10:26 ianbjor
+ Updated for April 1998 distribution.
+ Revision 4.28 1998/03/08 08:35:55 ianbjor
+ Updated for March 1998 distribution.
+ Revision 4.27 1998/03/08 08:24:37 ianbjor
+ Added new section about carpeting enclosures.
+ See (see Section 4.11).
+ Revision 4.26 1998/03/08 08:06:58 ianbjor
+ Finally added information about how to build an enclosure.
+ See (see Section 4.5).
+ Revision 4.25 1998/03/08 07:34:18 ianbjor
+ Added Mike Harmon's updated and expanded section about bridging.
+ See (see Section 3.5).
+ Revision 4.24 1998/02/09 08:29:13 ianbjor
+ Clarified symbol notation for Impedance (using 'Z' instead of 'I').
+ (see Section 5.9).
+ Revision 4.23 1998/02/09 02:22:24 ianbjor
+ Updated for February 1998 distribution.
+ Revision 4.22 1998/02/09 02:18:32 ianbjor
+ Added section about how distortion destroys speakers.
+ (see Section 5.22).
+ Revision 4.21 1998/02/09 01:41:34 ianbjor
+ Added information about using too much or too little power with
+ (see Section 5.21).
+ Revision 4.20 1998/01/06 15:51:02 ianbjor
+ Updated for January 1998 distribution.
+ Revision 4.19 1997/12/09 08:06:21 ianbjor
+ Updated for December 1997 distribution.
+ Revision 4.18 1997/12/09 06:43:00 ianbjor
+ Added section describing why kickpanels are a popular mounting
+ (see Section 5.19).
+ Revision 4.17 1997/12/09 06:14:35 ianbjor
+ Added section on building Kick panels.
+ (see Section 5.20).
+ Revision 4.16 1997/11/17 09:12:55 ianbjor
+ Removed useless reference in stiffening capacitor section.
+ (see Section 2.9).
+ Revision 4.15 1997/11/16 17:26:05 ianbjor
+ Small changes in introductory text.
+ Revision 4.14 1997/11/13 10:41:29 ianbjor
+ Updated for November 1997 distribution.
+ Revision 4.13 1997/11/13 10:38:42 ianbjor
+ Fixed typo and incorrect logic in noise troubleshooting logic.
+ (see Section 2.1).
+ Revision 4.12 1997/10/06 23:04:13 ianbjor
+ Updated for October 1997 distribution.
+ Revision 4.11 1997/09/07 20:18:21 ianbjor
+ Fixed omission in section on setting gains with an Oscilloscope.
+ (see Section 5.18).
+ Revision 4.10 1997/09/07 00:44:05 ianbjor
+ Updated for September 1997 distribution.
+ Revision 4.9 1997/09/06 01:07:08 ianbjor
+ Added section on setting gains with an oscilloscope.
+ (see Section 5.18).
+ Revision 4.8 1997/09/06 00:31:15 ianbjor
+ Fixed Changes Section to include complete 4.x history.
+ Revision 4.7 1997/09/06 00:24:46 ianbjor
+ Added Changes section.
+ (see Section 9).
+ Revision 4.6 1997/09/06 00:02:41 ianbjor
+ Added section descirbing how to determin speaker polarity.
+ (see Section 5.17).
+ Revision 4.5 1997/09/05 22:22:20 ianbjor
+ Added section about Line Drivers.
+ (see Section 3.31).
+ Revision 4.4 1997/09/05 20:38:42 ianbjor
+ Added section covering speaker sensitivity and the resulting SPL.
+ (see Section 4.2).
+ Revision 4.3 1997/09/05 20:27:59 ianbjor
+ Added section about using subwoofers in the winter.
+ (see Section 4.10).
+ Revision 4.2 1997/09/05 18:18:25 ianbjor
+ Fixed minor wording error in crossover design section.
+ (see Section 5.13).
+ Revision 4.1 1997/08/06 22:40:25 ianbjor
+ Updated for August 1997 distribution.
+ Revision 4.0 1997/07/11 08:12:32 ianbjor
+ Updated FAQ to Texinfo format.
ian d bjorhovde -> email@example.com
internet mobile audio -> http://mobileaudio.com