Pretty new to audio.
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Author:  racycle [ November 22 2011, 4:22 AM ]
Post subject:  Pretty new to audio.

I am pretty new to the audio scene. I was wondering what advice you guys could give for me. Trunk space is not a issue for me but I want to achieve heart pounding bass. The other day I stopped at a red light and a silver mercury pulled up beside me. I could feel his bass in my chest as if it were my own heart beat. This is the desired outcome I would like to achieve.

I have been planing to fill most of my trunk with a box and then make a fiberglass "face" for it. To have the strength and sound of a full MDF box with a nice to look at box. As far as what subs to get, what kind of amp , the difference in 2ohm and 4ohm, I haven't even taken a chip off the ice burg in researching.

also I bought a 1000watt Sony Xplod amp from Walmart and a simple wiring kit so I could play with the 2 12" 1200watt pyle subs a friend gave me.

Author:  Ryan [ November 22 2011, 10:43 AM ]
Post subject:  Re: Pretty new to audio.

Woah woah woah.

Hold onto your ponies.

Car audio is mostly science, some art, and a bit of black magic.

First of all, I am not an expert here, but I know enough to get me by. There are other members on here that compete in competitions and such, if anything they say conflicts what I say, go with them.

Second, here is an email I wrote to a younger buddy I have:


First things first, the lingo.


There are tow important types of power in this type of s---, and since you're going into electrical (no?) then you should grasp this fairly easy.

Peak power: This is the maximum amplitude of the sinusoidal waveform, from 0 volts to x volts. Peak-to-peak is twice the peak power, that is, from -x volts to +x volts.

RMS power: root-mean-square. This is the peak power multiplied by 1/root 2, which works out to 0.707. You'll need to know that in life. house power is actually 170v peak, and 120 RMS. The RMS power represents the "average" power.

RMS is what you care about. Neglect anything written on the box of the s--- you're buying but the RMS (sometimes called "continuous") power. If it says A MILLION WATTS PEAK POWER WOWZORS AWESOME" f--- it, its marketing bulls---. You can do whats called "wall socketing" a speaker. You literally plug it into the 120v house outlet, and it will garble for a minute before letting the magic smoke out. This is roughly 14 000 watts, and any speaker will take it for a second or two. Doesn't mean you care. This goes for decks, amps, speakers, anything that reports a wattage.


Humans can hear roughly 20-20000 Hz. A Hertz (Hz) is a unit that means cycles/second. A clock ticks at 1 Hz. In speakers, this describes how many times the speaker is vibrating in a second.


You know. There are low, mid, and high range. This describes what frequency the speakers are good at making.

high range (typically 2000- 20 000 hertz (Hz) - tweeters
mid range (200 - 2000 Hz) - just speakers, mids.
low range (20-200 Hz) - woofers, or subwoofers.

If a speaker is asked to do all three jobs, it typically sounds like s--- because it can't vibrate at so many frequencies at once. This is why having more than one type (than just the stock four cones in the doors) is good. There are two kinds of systems you can get into:

1. Coaxial speakers. Coaxial means they share the same center point, super typical of an aftermarket speaker. This picture is a tweeter coaxial with a mid range: ... _2_449.jpg The term has become abused, and now pretty much refers to any speaker unit that has more than one speaker in it.

2. Component speakers. This means that each range speaker is a separate unit, with separate wiring, mounted in different locations, etc. The benefit to this is primarily sound quality, as the speakers aren't interfering with eachother, and you can tune them by putting them in different locations. Also, they often come with external crossovers for further tunability.


The audio signal from a normal deck comes out with all the frequencies, 20- 20 000 Hz. Since some types of speakers only want to play a range, they need a way to filter that. Thats where crossovers come in.

A crossover is a device that uses capacitors and inductors (electrical bits that you've likely seen before but haven't put a name to) to filter the signal. Capacitors are usually a high-pass filter, so they let the high frequencies through but block the low ones. Inductors are low pass. There are two types of crossovers, passive and active.

Passive: On a coaxial speaker, a typical one with a mid range (all range, really) and a tweeter, is you'll see a little capacitor before the tweeter, like so: ... 024-90.jpg. That looks like a home-brew hackjob, but thats the idea. they call it passive because its unadjustable, and works when the speaker works.

Active: This is what you find in your stock deck, when you tune the treble and bass. Its using vaiable capacitors and inductors to change the output. These are also found as little external boxes that split the signal for a component speaker set, or within an amplifier to change the range it amplifies. This is also the principle a radio works on.


There are several types of amplifiers, and they all work on the blue smoke majik that is electronics, but this is what you need to know: they make s--- louder.

but, you can make s--- loud and sound like s---, or make it loud and sound like sex. If you like dubstep, you want that second option there.

Loud and shitty: Buy the cheapest amp you can find. That pretty much sums it up.

Loud and sexy: Buy the correct amp for your application. Things to consider:

A) How many speakers are you powering?
-this determines how many "channels" you want to run. A channel is basically a +/- set of wires (two wires) to run to a speaker. So if you're doing 4 door speakers, buy a 4 channel.

-there's a hitch here, you can wire your speakers in parallel or series. Lets say you have 2 speakers.
-- If you wire 2 4ohm speakers in series, you get 8 ohms. you probably know this.
-- If you wire 2 4 ohm speakers in parallel, you get 2 ohms.

Keep in mind you aren't gaining or losing anything doing this, you still use the same net power.

B) What resistance are the speakers you're running?
A lower resistance speaker will take more current, and therefore more power with the same given input from an amplifier. This doesn't mean a 2 ohm sub is better than a 4 ohm one, though. Just know what you're working with, and see where your amplifier is efficient. It will normally list a few different outputs for given resistances.

Side note, what is DVC, Dual Voice Coil. this is a speaker with two internal coils. Marketing BS again, but it gives you the opportunity to run it in parallel or series to change its resistance. ( a 2 ohm DVC sub can be wired for 4 ohms or 1 ohm. )

C) what type of speakers are you running?
there are a few types of amps out there, some are designed for anything, some are designed for subs only, and some are designed for midrange only. Check to see what crossover capabilities they have (low pass filter, high pass filter, adjustable crossover, words like that)

A typical class is a "class D" amplifier. This is a workhorse. Typically sounds like s---, but can pump out the power. Usually this is for subs. If its a single channel, they'll likely call it a "monoblock".

D) What power range your speakers are in

If you want to save money on the amp, ignore this. But if you care how it sounds, buy an amp with 10% or more RMS power than your speakers are rated for.

This is to avoid a phenomenon called clipping. Clipping is when the amplitude of the output exceeds the amplitude the amplifier can provide. Here's a picture, because thats easier to get.

Clipping: Clipping sounds like s---, because you're basically feeding the speaker a DC power signal for a short moment, which sounds terrible. If your amp can provide more power than your speakers can take before meltdown, this won't ever happen.

This is also a good way to ensure you never blow your amp.

Bridging: Some amplifiers support what is called "Bridging" which is best described as feeding one channel's output into the amplifier again, to be amplified, and put out in another channels output. So you're combining two channels into one to increase power output. This is handy, but don't use it unless you have to, because its harder on the amplifier.

I think thats about it for amps.


Pretty straightforward. the RMS output of any aftermarket deck likely isn't over 20w/channel. s--- eh? the number they report on the box is peak power, of all channels combined ( 50w x4), so when you see 200W power, read 80W RMS total. Not so sexy anymore eh?

A pre-amp output is pretty much a signal already prepared for a subwoofer. Its fed through a low pass already, and at a low amplitude just like amplifiers like to receive it. This also allows you to adjust your sub from the deck, handy.

RCA inputs: this is how you hook up most aftermarket s---. Its the red/white connectors like on a playstation or N64. (yellow on those is the video)

3.5mm jack: this is the same type of connector that headphones use. Becoming obsolete with bluetooth and usb s---, but still nice option.

USB: you know what this is, any deck with USB will have MP3 support as well.

Bluetooth: If and when you get a smartphone, you can have them connect automatically, no wires, fancy, easy.

Internal crossover. If you like how your music sounds, you want this. Aim for as many channels as you can get.

Am I forgetting anything?

Oh yeah, shapes.

A round speaker sounds best, end of story. Oval speakers are marketing BS, and will make less noise per power input, and sound like s---. Square subs are bulls---. Same with triangles. All bulls---. Buy round speakers.

Also, never mix up the +/- on speakers. Always do it right, or the speaker will play 180ยบ out of phase, which means that it will cancel out the sound waves of the other speakers. You should learn this too in electrical.

Brands to look at:

Pioneer (headunits)
Alpine (eh, not too great actually)
Rockford (amps)
Focal (god,but expensive)
Polk (subs, speakers, amps)
JL Audio (amps, subs)
Clarion (amps)
JBL (speakers, amps)
MTX (subs)
Anything that isn't cheap.

Brands to avoid like the plague:
Most of Sony's stuff from the 90's and early 00's
Whatever speakers Kayla has in her car.
Anything you've never heard of and looks sketchy.

Start with that.

Author:  racycle [ November 22 2011, 1:01 PM ]
Post subject:  Re: Pretty new to audio.

Ah wow! I think you covered just about everything haha. Thanks a lot man , I really appreciate it. For new subs, I was thinking of ether MTX or JL.

One of my friends was running 2 MTX 12"s in his SUV with some older amp that was roughly 2-3 ft long and anything over 2 on the amp would blow just about anything he had. His was clean and loud but missing the deepness.

Another friend has been using 2 JL 12"s in his eclipse with a ported box and a sony xplod amp and head unit. His results were not that bad but still fell short.

Also What are your thoughts about my box idea? I saw a guide on here using packing peanuts to measure volume, I will try that along with the fiber glassing the inside corners to be rounded when I go to make mine.

What can you tell me about ported/sealed inclosures? I have seen many different setups for ported like porting outside the box,longer ports inside,hallways inside the box. What would I use to figure out what would be the best route to take?

Author:  neuspeedescort [ November 22 2011, 9:23 PM ]
Post subject:  Re: Pretty new to audio.

im going to say this and your going to need to listen and understand im not coming down on you. do some research. if you want to do this yourself and not pay others you have to put the time in. i didn't get to where i am asking people for handouts. granted you stated first thing you where a noob. but i see you have been a board member for over a year so you understand reading and people telling others to use the search function. im talking on a bigger scale though. search the internet and absorb.

Car audio is mostly science, some art, and a bit of black magic.

bingo! rarely does something work twice. i have built a lot of boxes and in different designs and configurations. never has the outcome been the same. the cabin space of a car has to many variables.


Author:  Sleeper6 [ November 22 2011, 11:25 PM ]
Post subject:  Re: Pretty new to audio.

Dont forget about volume and dampening! The same sub will sound different in 2 different boxes, make sure you know the spacial requirements.

Author:  Polonius [ November 23 2011, 1:03 AM ]
Post subject:  Re: Pretty new to audio.

Like others have said: read, read, read...... There's a heck of a lot of science involved.

In answer to your ported/sealed question, I have a question for you - how low do want it to go?

If you can't answer with something like "20 Hz", 30, 50, etc.... Just answer with the kinds of music you will listen to.

Rap, Dubstep, Metal - these tend to go quite a bit lower than Rock, Techno, Country, etc.

A browse through the threads in this forum will give you hours of education. Do it at least once.

Author:  neuspeedescort [ November 23 2011, 2:08 AM ]
Post subject:  Re: Pretty new to audio.

i doubt he is going to understand the hertz question of your answer. tuning frequencies and crossover points is part of the "black magic". however he will know the music genre point of the question.


Author:  Polonius [ November 23 2011, 7:34 PM ]
Post subject:  Re: Pretty new to audio.

True. Figured it didn't hurt to ask. I'm still pretty green to the car audio thing, but I know I like it good and strong at 30 Hz or so.

Author:  CarolinaCartel [ November 23 2011, 10:26 PM ]
Post subject:  Re: Pretty new to audio.

Mtx & Jl are good companies. But there are brands that u can get for less and are better then those brands. Ty this company They have very good amp and subs. Stay away from the stetsom stuff on the site. That stuff is mainly for comp and don't really do well in daily setups. Almost these are real wold rated amps. By that i mean these add make power at 12 volts not 14.4 like most of the bigger companies rated there amps. Example the Audioque AQ1200D does 1200 wrms @ 12volts and does 1470 @14.4(cost 269) Mtx Thunder1501D does 1120 @ 12volts & 1490 @ 14.4 (cost 699). Do your homework before you spend you money.

Author:  Ryan [ November 23 2011, 10:31 PM ]
Post subject:  Re: Pretty new to audio.

^ This is the info I wish I knew. Which lesser-known brands aren't s---.

Feel like compiling a list?

Author:  CarolinaCartel [ November 23 2011, 11:41 PM ]
Post subject:  Re: Pretty new to audio.

Ryan wrote:
^ This is the info I wish I knew. Which lesser-known brands aren't s---.

Feel like compiling a list?

No but I'll list some good companies I have personally know to be good.

Audioque: good amps & subs. Speaker(mid/Tweeter) sound ok nothing special.
Direct Internet sale from Manufacturer.

DC Sound Lab: Great Subs(get loud off a little bit of power. Amps just came out haven't tied them yet.
Sales thru Dealer or sales rep. Image (putting of these suds in my mx-3)

Sundown Audio: The best brand on the market(IMO)
Sales thru Dealer, , or sales rep Image

SKAR AUDIO: Great budget Subs
Sales thru Dealer, , or sales rep

Obsidian Audio: Great budget Subs. Amps coming
Direct Internet sale from Manufacturer

I have used all of these bands. They make very good audio gear and have great customer service unlike the larger companies.

Author:  neuspeedescort [ November 24 2011, 2:05 AM ]
Post subject:  Re: Pretty new to audio.

whaaaaa! no love for DD?


Author:  CarolinaCartel [ November 24 2011, 8:59 AM ]
Post subject:  Re: Pretty new to audio.

neuspeedescort wrote:
whaaaaa! no love for DD?


I'm about to get a pr. of DD M1C amps. I didn't list them Because they aren't for someone on a budget. But they make great products. There Germans components are the best sounding components i have ever heard.

Author:  neuspeedescort [ November 24 2011, 3:20 PM ]
Post subject:  Re: Pretty new to audio.

im a DD dealer so i had to put it out there.

the 500 and 1000 series subs and most the C-series amps are with in a "budget" price IMO. i have heard a lot of good things about the germans but have yet to be able to sell any or do work on my own car with them. the M1c is going to do work!


Author:  CarolinaCartel [ November 24 2011, 6:27 PM ]
Post subject:  Re: Pretty new to audio.

neuspeedescort wrote:
im a DD dealer so i had to put it out there.

the 500 and 1000 series subs and most the C-series amps are with in a "budget" price IMO. i have heard a lot of good things about the germans but have yet to be able to sell any or do work on my own car with them. the M1c is going to do work!


I'm hoping they do work. I'm taking aim at the 0-2500 watt Wall class. Looking to do mid 150's with my setup. Want to show people that you don't need 10k watts to do 150. 1 extra battery & 1 run of 1/0ga wire. Think it can be done?

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