Building a nice sounding system

[aspekt9]

Ok, I'm semi new to all this car audio stuff. I'm looking to make my next purchases toward my system. Now my goal for this system is to have an awesome sounding system where you don't hear just bass. Don't get me wrong, I'm looking to have 2 10s or 12s but I want to actually hear the MUSIC part. Now to start, I have an Alpine CDE 9845 Head Unit, 2 Dual 120 Watt 2-way speakers in the front and 2 Alpine type-s 250 watts in the back. Now here's where I'm lost. I'm starting to look at amps and subs and a lot of terminology is used that I don't really comprehend such as crossovers or bridged amps. So here's my question: What should I purchase next for clear sound and a deep bass. My budget for an amp and subs is probably around $300-$400. Also, what does an amp actually do? If I have my bass at 5 and turn the volume up to around 20 I get distortion. Is this due to the speakers or the lack of an amp/sub? Thanks for all the help in advance...

 

[TrboANTsi]

the interior speakers arent made for bass thats why they get distorted..sooner or later they will blow, so try not to kill them with bass. My suggestion is to get a 2 10inch alpine type Rs and a nice amp that will push. Currently I have 2 type X subs and an Earthquake PHD 2000. If you trust in ebay i think you could get the type Rs and that amp in your budget then go buy a box for another 50. The alpine headunit hopefully has a built in crossover and a seperate preamp output for the subs. If it does your life will be soo much easier. By the way the alpine subs and amp combo i have will hurt your ears so i dont know if your looking for that much bass. Couple of friends of mine use Solobarics those thump too, but its all up to personal flavor. Also for the future look into a simple 4 channel amp for your interior speakers they will sound much better then being powered from the headunit. hope this helps! Oh the amp just supplies extra power to feed the subs. Most subs need more power then the headunit can supply so an amp amplifies the power keeping it simple

 

[aspekt9]

Thanks for the quick reply. I checked the installation manual and it says it has 2 pre-amp outputs with subwoofer level control. Not sure about the crossover thing you mentioned

 

[DGajre777]

Start reading...
http://www.crutchfieldadvisor.com/S-RCeJpfyqr6l/learningcenter/car/audiocomponents.html
http://www.crutchfieldadvisor.com/S-869V8PMcxSl/learningcenter/car/?listAll=1
http://www.carstereo.com/help/Articles.cfm

If you want good audio, you need components in the front, not regular speakers. Your CD player needs an equalizer good crossovers with selectable octave settings, high volt pre amp outputs, etc. Read the stuff above and post if you have questions. There is a LOT to learn about car audio.

 

[kenamond]

All a crossover does is screen out certain frequencies to certain speakers. For example, you want a low-pass crossover to permit low frequencies to pass to your subs, but you want high frequencies to pass to your tweets. A band-pass filter will permit a range of frequencies to pass to your mids. An equalizer is just a whole bunch of these things operating together.

An amplifier takes the low power signal from your head unit and amplifies it so that it can push the speaker cones and make audible sound. The signal from your head unit is probably 6V and low amperage which isn't designed to drive a speaker, but the amp will boost this up to a much larger value - speakers require amplification of the signal. Many head units send signal at 4V, but 6V is better. The signal will be altered by the electronics in your car, but this noise is like background noise to the actual signal. 4V is like talking in a crowd of whispers, but 6V is like yelling, so the music comes through much more clearly over the whisper of noise.

I've been out of the loop for too long to recognize your Alpine head unit model, but based on the response of others, it has a built-in amplifier. You may be able to drive your mid and high range speakers (6x9, tweets, etc.) with the head unit amp, but you'll need much more power to drive the subs. Depending on the RMS wattage of your head unit's amp, you may still want more power to drive the non-sub speakers.

When you buy subs, they'll often recommend enclosure/box volumes, and there are "musical" and "efficiency" dimensions (two different possible boxes in which you can mount the subs). The musical box will be less efficient (require more amplification) but will produce a more pure reproduction of the lower frequencies. The efficiency box will be most efficient at the cost of bass accuracy. It's a trade-off of good sound versus louder sound. If you want the musical enclosure, you'll need more amplification to get the same decibel (sound pressure) as an efficiency enclosure with less amplification.

I have an older, non-amplified Alpine head unit which has 6 outputs: 4 for the interior speakers - front left/right, rear left/right, and 2 more for a dedicated subwoofer pair (this signal is sent through a built-in low-pass filter, so that only the low frequencies are passed to the subs). I also have one 4-channel amp to handle the interior speakers and a 2-channel sub amp to handle the subs (2 10" subs in a musical enclosure).

Bridging an amp means that you run the two subs in parallel as one mono speaker. This ends up lowering the resistance of the pair which means that the amp can provide more power. There are electrical equations that you can find to describe this, but that's the basic idea. However, your amp must be able to drive speakers at that lowered resistance; some can, some cannot. Typical subs have resistances of 4 ohms, and running them in parallel gives an aparent resistance (to the amp) of 2 ohms. Some amps can handle resistances of 2 or 1 ohm or even lower, but some will overheat if pushed that low. Many cheaper amps are designed for a 4 ohm minimum resistance. Check the specs of the amp.

I agree with DGajre777 about reading up on this. I just gave you a taste.

 

[aspekt9]

Alright, I've been reading quite a bit from the artciles you guys posted, thank you for all the information. Would it be better for me to have 2 amps instead of one? 1 to power the speakers the other to power the subs? Also what are some good brands for AMPs? Thanks again guys.

 

[a_scobel]

Since you're into clarity & don't care too much for bass, may i suggest the Infinity Basslink..I bought mine two years ago for $200 on Ebay, I'm sure they've gone down in price since then. 10" sub with a built-in amplifier, it gives me all the bass I need. Plus it's pretty compact..I can get a picture of it in my trunk when I get home from work in 7 hours.

My setup:
Pioneer DEH-P7400MP headunit
Alpine Type S 2-Way 6x9's in the back
JBL 3-Way 6½'s in the front.
Stock amp
Infinity Basslink

Total cost for the speakers & sub was around $380.

The only system I've heard that sounds better are those cars that come with premium Bose systems. & I'm using the stock Infinity amp..one of these days I'll rewire the whole system & get rid of the stock amp & I'm sure it'll make it sound even better.

 

[TSIMonsteR]

Since you're into clarity & don't care too much for bass, may i suggest the Infinity Basslink...

I agree. Compact, Looks good, and sounds good. Most of all, its simple

Personally, I have:
2 MTX Component 6.5" up front pushed by an MTX 282
2 Infinity 6x9's in the rear pushed by and MTX 202 (at low volume)
and an MTX 10" 8000 in the back in a teeny tiny custom built box pushed by an MTX 421D

This is the best setup I have ever had/heard in any car and costed far less then you think. I got all 3 amps off ebay for $180, the brand new MTX high end speakers for $65, and the infinitys were free.

I highly recommend getting a quality amp to at least push your front speakers b/c that is mostly what you hear. speakers play 97% of the music, while the subwoofer takes up the other 3%. I can crank it all the way up and never hear any distortion (you have to get out of the car at this point b/c it hurts), but more importly, it is crystal clear at the lower volumes that I use on a daily basis. If you want some good deals on some MTX stuff, shoot me a pm. Also, I have installed numerous car stereos, so if you have any q's, feel free to pm about those as well

 

[kenamond]

Also keep in mind that some folks have more refined taste in audio fidelity than others. Before you take blind advice, I'd try to listen to some sound systems (can be any car) and decide what you like and what you don't and how much it will cost to get what you want or atleast can live with.

I highly doubt I'd like a $300 complete setup very much, but you may love it.

I disagree that bass is only 3% of the music. If you have very nice bass (not talking rap or anything, just clean low frequencies from ~20Hz up) and turn it off, you will *REALLY* notice it - much more than if you turn the tweets down, for example.

BTW, I have:
BA tweets
MB Quart 6.5 midbass in doors
MB Quart 6x9 coax in rear
2x10" Phoenix Gold XMAX subs in musical enclosure
Alpine CDA-7930 head unit
Alpine 6-disk changer
Phoenix Gold ZX450 4-channel amp for the cabin
Phoenix Gold ZX500 2-channel amp for the subs

The sub box is against the rear seats between the rear wheel wells, and I have a false floor/deck hiding the changer and amps which are one a shelf that still opens like the stock "trunk", so I still have my spare tire under the amps. I can actually get at my spare in under a minute. It's all carpeted to match the stock interior.

I still have enough room in my trunk for groceries

 

[aspekt9]

Now TSIMonsteR you have three amps, one to power the front, one to power the back and one for your sub. I've never heard of MTX are they a quality brand? Is it best to have 2 AMPS one to power the front speakers and one to power the back or is it ok I you just have one amp to power the front AND the back? Also if you could get me a link to all three of those amps that'd be great. Also, kenamond do you have a picture of your trunk setup?

 

[a_scobel]

Now TSIMonsteR you have three amps, one to power the front, one to power the back and one for your sub. I've never heard of MTX are they a quality brand? Is it best to have 2 AMPS one to power the front speakers and one to power the back or is it ok I you just have one amp to power the front AND the back? Also if you could get me a link to all three of those amps that'd be great. Also, kenamond do you have a picture of your trunk setup?

Depends on what kind of amp you get..Obviously a 4-channel 2000w amp is going to power your system a little better than a 4 or 2-channel 200w amp. It depends what kind of amps you can afford or get your hands on. A 4 or 6 channel amp with lots of power will be fine for powering your front & back speakers.

Here's some pics of the basslink in the trunk in case you were wondering

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[aspekt9]

Ok, the speakers in my front are rated at 120 Watt max at 30 RMS and the back are 250 watt max, 50 RMS, the amp I get should I base it on how much RMS it can output meaning I would need an amp that atleast outputs atleast 80 watts?

 

[jarredsyxx]

Since you're into clarity & don't care too much for bass, may i suggest the Infinity Basslink..I bought mine two years ago for $200 on Ebay, I'm sure they've gone down in price since then. 10" sub with a built-in amplifier, it gives me all the bass I need. Plus it's pretty compact..I can get a picture of it in my trunk when I get home from work in 7 hours.

My setup:
Pioneer DEH-P7400MP headunit
Alpine Type S 2-Way 6x9's in the back
JBL 3-Way 6½'s in the front.
Stock amp
Infinity Basslink

Total cost for the speakers & sub was around $380.

Couldnt agree more... the Basslink is ASTOUNDING in a hatchback...you won't regret it...plus you get a gain control you can mount somewhere at arms length to be able to adjust for maybe changes in music genre... I got Pheonix Gold Component set...and I love them... got em off ebay... just dont go to the cheaper really poorly built equipment and you will be fine with whatever you chose...

 

[aspekt9]

If I have speakers in the front and the rear that can handle 50 watt RMS would a 4 channel amp with 50W RMS x 4 @ 2 Ohms and 40W RMS x 4 @ 4 Ohms power the speakers enough? I was looking at this amp: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270003174255 Can someone explain the whole 2 Ohm and 4 Ohm thing to me please.

 

[kenamond]

If I have speakers in the front and the rear that can handle 50 watt RMS would a 4 channel amp with 50W RMS x 4 @ 2 Ohms and 40W RMS x 4 @ 4 Ohms power the speakers enough? I was looking at this amp: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270003174255 Can someone explain the whole 2 Ohm and 4 Ohm thing to me please.

The 2 vs 4 ohm numbers are the resistance of the speakers. If you think of an analogy of electrical current to water flow, the gallons of water per second is like current (in Amps), the pressure applied to the water pipes, etc. is voltage, and restrictions in the pipes is resistance. You can think of it this way: You have big pipes that can flow water into a valve and then on to something else. A pump is providing pressure to force the water through the pipes. The pipes are your speaker wires, the pump is your amplifier, and the valve is your speaker. If you close the valve more or less, the resistance to the water flow goes up or down, respectively. If you have a 2 vs 4 ohm speaker, the 2 ohm speaker has less resistance and can flow more electricity than the 4 ohm speaker at the same voltage (pressure); it has a bigger valve.

Now, here are some simple equations:

1) V=I*R, where V is voltage, I is current, and R is resistance. For a 2 ohm speaker with the same voltage applied to it as a 4 ohm speaker, it will flow twice the current as the 4 ohm speaker.

2) P=I*V, where P is power (wattage), and I and V are still current and voltage. If you stick the equation (1) for V in place of V in equation (2), you get:

3) P = I*I*R.

Now the current is what actually moves your speaker, so more current means louder music.

So when you run 2 ohm speakers versus 4 ohm speakers, you get more current (louder) to your speakers for the same power output. However, amps have a maximum output, and can't drive speakers below some minimum speaker resistance without overheating.

Another handy fact is that if you take two 4ohm subs and run them in parallel (put the + and - of each on the + and - terminal of your sub amp, the resistance that the amp "sees" for the pair is 2 ohms. Thinking of water, you have two valves in parallel, so the water is split between the two, so it can flow twice as much. If you run four 4ohm subs in parallel, the resistance the amp "sees" is 1 ohm; there are four valves to share the flow of water, so it can flow four times as much.

Lower resistance speakers are more efficient, so your amp's wattage goes farther (makes louder music for the same wattage), but it is also harder for your amp to do this, and there is a lower limit on the speaker resistance it can drive without blowing a fuse or overheating.

 

[DGajre777]

Good post Kenamond.

Most car speakers are 4 ohms. If you have 2 x 50 RMS watts in the front and 2 x 40 RMS watts in the back, you can get 4 x 40 RMS watts rated at 4 ohms and they will be enough. When you look at amps, make sure it has the word RMS in the power rating.

When you get subs is where you can mix and match impedance (4 ohm or 2 ohm ratings). If you have a 400 Watts RMS sub, you can get a amp that puts out 200 x 1 RMS at 4 ohms, the same amp might put out 400 x 1 RMS at 2 ohms, this is because of less resistance as Kenamond mentioned above. Now add dual 4 ohm or dual 2 ohm subs and you have to carefully pick your amp to get the most power out of your amp.