Car Audio FAQ
Frequently Asked Questions in the rec.audio.car
This is the FAQ list for the Usenet newsgroup rec.audio.car,
maintained by Ian D. Bjorhovde , with
contributions from many other people (see Section 8). The contents of
this document are based on the contributors' opinions; neither the
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1.0 Definitions
- 1.1 What do all of those acronyms mean? [JSC]
- 1.2 What is meant by "frequency response?" [JSC]
- 1.3 What is a "soundstage?" What is an "image?" [CD]
- 1.4 What is meant by "anechoic?" [JSC]
- 2.1 My speakers make this high-pitched whine which matches the engine's RPMs. What is it, and how can I get rid of it? [IDB]
- 2.1.1 Level 1: Check out the Amplifier(s)
- 2.1.2 Level 2: Reduce the System
- 2.1.3 Level 3: Move the Head Unit
- 2.1.4 Level 4: Testing the Car
- 2.1.5 Level 5: Adding Signal Processors
- 2.1.6 Level 6: Processor Isolation Tests
- 2.2 My system "pops" when I turn it off. What is happening and how can I get rid of it? [JD]
- 2.3 What is the best power wire to use? [JSC]
- 2.4 What is the best speaker wire to use? [JSC, JW]
- 2.5 I heard that I should run my power wire directly to my car's battery. Why should I bother, and how do I do it? [JSC]
- 2.6 Should I do the same thing with my ground wire, then? [JSC, IDB]
- 2.7 Sometimes when I step out of my car, I get a really bad shock. What is wrong with my system? [IDB]
- 2.8 When my car is running and I have the music turned up loud, my headlights dim with the music. Do I need a new battery or a new alternator? [CD, MO]
- 2.9 What is a "stiffening capacitor", and how does it work? [JSC]
- 2.9.1 Do I need a capacitor? [MZ]
- 2.9.2 Can I just upgrade my headlight wiring instead? [MZ]
- 2.9.3 Will the dimming go away if I upgrade the amplifier power/ground wiring? [MZ]
- 2.9.4 What do I look for when buying a capacitor? [MZ]
- 2.9.5 How do I install a capacitor? [MZ]
- 2.9.6 I have more than one amp in my audio system. Which one should I have the capacitor run? [MZ]
- 2.9.7 Will my bass response improve by adding a capacitor? [MZ]
- 2.10 When should I upgrade my battery or add a second battery? [IDB]
- 3.0 Components
- 3.1 What do all of those specifications on speakers mean? [JSC, CD]
- 3.2 Are component/separates any better than fullrange or coaxials? [JSC, DK]
- 3.3 What are some good (and bad) brands of speakers? [JSC]
- 3.4 What do all of those specifications on amplifiers mean? [JSC, BG]
- 3.5 What does "bridging an amp" mean? [MHa]
- 3.5.1 Why should I bridge my amp?
- 3.5.2 Why shouldn't I bridge my amp?
- 3.5.3 What happens when an amp is bridged?
- 3.5.4 Does bridging an amp would halve the impedance of the speakers?
- 3.5.5 Can I bridge my 4 channel head unit?
- 3.6 What is "mixed-mono?" Can my amp do it? [JSC, IDB]
- 3.7 What does "two ohm stable" mean? What is a "high-current" amplifier? [JSC]
- 3.8 Should I buy a two or four (or more) channel amplifier? [JSC]
- 3.9 What are some good (and bad) brands of amplifiers? [JSC, IDB]
- 3.10 What is a crossover? Why would I need one? [JSC]
- 3.11 Should I get an active or a passive crossover? [JSC, JR]
- 3.12 Should I buy an equalizer? [JSC]
- 3.13 What are some good (and bad) brands of equalizers? [HK]
- 3.14 What do all of those specifications on tape deck head units mean?
- 3.15 What are features to look for in a tape deck?
- 3.16 What are some good (and bad) brands of tape decks?
- 3.17 What are features to look for in a CD head unit?
- 3.18 Should I buy a detachable faceplate or pullout CD player? [IDB]
- 3.19 What are some good (and bad) brands of CD head units? [HK]
- 3.20 Can I use my portable CD player in my car? Won't it skip a lot? [JSC]
- 3.21 What's that weird motor noise I get with my portable CD player? [JSC]
- 3.22 What are some good (and bad) brands of portable CD players?
- 3.23 What's in store for car audio with respect to MD, DAT and DCC? [HK]
- 3.24 Are those FM modulator CD changers any good? What are my other options? [PW, JGr]
- 3.25 What kind of changer will work with my factory head unit? [PO]
- 3.26 What are some good (and bad) brands of CD changers?
- 3.27 Why do I need a center channel in my car, and how do I do it? [HK, JSC]
- 3.28 Should I buy a sound field processor? [DK]
- 3.29 What are some good (and bad) brands of signal processors? [IDB]
- 3.30 I keep hearing that speakers for Company X are made by Company Y. What's the deal? [IDB, DK]
- 3.31 What is a Line Driver? Do I need one? [LC,IDB]
- 3.32 Can I play MP3 files in my car? [AK]
- 4.0 Subwoofers
- 4.1 What are "Thiele/Small parameters?" [CD, RDP]
- 4.2 How does speaker sensitivity affect real world SPL? Will a higher sensitivity give me a larger SPL? [MS]
- 4.3 What are the enclosure types available? [JLD, JG]
- 4.4 Which enclosure type is right for me? [IDB, DK]
- 4.4.1 Infinite Baffle ("free-air")
- 4.4.2 Sealed Box
- 4.4.3 Ported Box
- 4.4.4 Bandpass Box
- 4.5 How do I build an enclosure? [AO]
- 4.6 MDF for Dummies [IDB]
- 4.6.1 What is MDF? [PS]
- 4.6.2 Where can I get MDF? [PS]
- 4.6.3 What type of saw blade works best when cutting MDF? [PS]
- 4.6.4 What type of router bits work well with MDF? [PS]
- 4.7 What driver should I use?
- 4.8 Is there any computer software available to help me choose an enclosure and a driver? [JSC, MH, DK]
- 4.9 What is an "aperiodic membrane?" [CD, DK]
- 4.10 Can I use my subs in the winter? [MS]
- 4.11 How can I carpet my enclosure? [AO]
- 4.12 Are large magnets always better than small magnets? [ST]
- 4.13 I know the box volume required for my subwoofer, but what are the best dimensions for my enclosure? [IDB]
- 5.1 Where should I buy the components I want? [JSC]
- 5.2 What mail-order companies are out there? [JSC, JM, MM, IDB]
- 5.3 What tools should I have in order to do a good installation? [JSC]
- 5.5 What is "rear fill", and how do I effectively use it? [HK, JSC]
- 5.6 How do I set the gains on my amp? [JSC]
- 5.7 How do I select proper crossover points and slopes? [DK]
- 5.8 How do I flatten my system's frequency response curve? [IDB, DK]
- 5.9 How do I wire speakers "in series" and "in parallel?" [IDB]
- 5.10 Are there any alternatives for Dynamat? It's too expensive! [MM, PK]
- 5.11 How many devices can I attach to my remote turn-on lead? [IDB]
- 5.12 How do I wire a relay in my system? [IDB]
- 5.13 How do I design my own passive crossovers? [JSC, JR]
- 5.14 How do I build my own passive crossovers? [JSC]
- 5.15 Can I split the single pre-amp output from my head unit to drive two amplifiers with a Y-cable? [IDB]
- 5.16 How do I turn a stereo signal into a mono signal [BW]
- 5.17 How do I determine a speaker's polarity? [IDB]
- 5.18 How can I use an oscilloscope to set the gains in my system? [AO]
- 5.19 Why are kickpanels such a popular location for mounting speakers? [ES]
- 5.20 How can I build custom kickpanels? [MB]
- 5.21 What's worse for a speaker, too much or too little power? [IDB]
- 5.22 Why is distortion harmful to my speakers? [RK]
- 5.23 What tools do I need to cut Plexiglas? [PS]
- 5.24 Are there any other special requirements for working with Plexiglas? [PS]
- 6.1 What is IASCA, and how do I get involved? [JSC, HK, IDB]
- 6.2 What is USAC, and how do I get involved? [HK]
- 6.3 What are the competitions like? [HK, CD, IDB]
- 6.4 Should I compete? [CD]
- 6.5 What class am I in? [HK, JSC]
- 6.6 Where can I find out when these Sound-Offs are? [IDB]
- 6.7 How do I get sponsored by a manufacturer? [CM]
- 7.1 What magazines are good for car audio enthusiasts? [JSC, MI, NML, JR]
- 7.2 Are there any newsletters I can read? [IDB]
- 7.3 What books can I read? [JSC, JW, TT]
- 7.4 Can I contact any manufacturers on-line? [IDB]
- 8.0 Credits
