What's wired to what?!? Help a noob out.

[tstein]

OK, so, the other day, I decided to drop by a local installer and purchase a car audio system....getting rid of the factory system. But I want to know more about how it's wired so that I can make changes to it if I want to later.

Let me fill you in on how this thing is setup....

This is a Chevrolet Silvarado 2003 standard cab. I mostly listen to rock\alternative and am by no means, a base head. I love the clean audio...mmmm!

First, the equipment used (I believe):

Kicker KS65.2 2-way 6.5" components (150W peak, 8-75W RMS, 4 ohms)

Cerwin Vega VMAX 10" (200W RMS, 600W Peak, 4 ohms)

Cerwin Vega XL-300.1 240W mono amp (1x280W into 4 ohms, 1x400W into 2 ohms)

Cerwin Vega XL-150.2 (2x50W into 4 ohms, 2x75W into 2 ohms)

Cerwin Vega HED-6.0 6" 2-way 40W speakers (40W RMS)

Alpine CDA-9853 with IPOD control box

Probox ported sub enclosure.

The sub in box and amps are located behind the seats. The components are in the front doors. The rear speakers are in the pillers (right behind the head at about ear level).

So, I believe the 10" sub goes into the mono amp. So the amp is capable of putting 280 watts into this 200W speaker. Seems like there is a potential for damage here right? Should I be making sure I don't turn the volume up too loud?

The 2 channel amp goes to the component speakers. Here is where I get confused. The components are actually made up of 4 total speakers with crossovers\filters. Does each door make up a "channel"? Or do the two tweeters in parallel make up a channel, while the two mids make up the second channel? Either way, it seems like 2x50W is a bit low for 75W speakers? Don't get me wrong....it sounds great AS IS. Whatcha think?

Ok, so that leaves the rear pillar speakers. They are supposidly driven directly by the head unit, which puts out 4x18RMS I believe. They sound WAAAY quiet compared to everything else. When the system is turned up to the point that the bass begins to hurt my wimpy ears, I have to put my ear directly on the speaker to even tell if it's playing. Did they bridge this power? Or if not, is 18W too little for these 40W speakers?

Now, to me, everything sounds good, but I'm left wondering:

1) If I have the head unit turned about half-way of the volume control, how much power is being delivered? Half? Am I going to blow the sub if I turn the volume up 3/4 or something?

2) The rear speakers are way too quiet compared to the other speakers. What can be done about this? Is it possible that the installers didn't provide enough power to these speakers? Hmmm

3) Do I understand how the components are wired to the 2 channel correctly?

Thanks for the help //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Tomas

Click to read more...

 

[squeak9798 5,000+ posts]

So, I believe the 10" sub goes into the mono amp. So the amp is capable of putting 280 watts into this 200W speaker. Seems like there is a potential for damage here right? Should I be making sure I don't turn the volume up too loud?

Unless you plan on playing test tones at full volume, not really. You should be fine. Worse comes to worse, just set the gains conservatively.

The 2 channel amp goes to the component speakers. Here is where I get confused. The components are actually made up of 4 total speakers with crossovers\filters. Does each door make up a "channel"? Or do the two tweeters in parallel make up a channel, while the two mids make up the second channel?

Each side's mid and tweeter are connected to a passive crossover that divides the frequencies between the mid and the tweeter. Each passive crossover (there are two, one for the left side one for the right side) is connected to one channel, left or right, and that passive crossover is then connect to the mid and tweeter on it's respective side (left or right)

The tweeter and mid in the driver's side door will be wired through a passive crossover to one channel, the tweeter and mid in the passenger's side door will be wired through a passive crossover to the second channel.

Either way, it seems like 2x50W is a bit low for 75W speakers? Don't get me wrong....it sounds great AS IS. Whatcha think?

I think it's perfectly fine, especially if you think it sounds good as is. 50w is a lot more acoustic power than people think it is. In all reality, with typical music content at an normal listening level, that amplifier is probably averaging a power output of around 5 to 10 watts. No think about how loud the speakers sound with music at a normal listening level. When you consider that....50w seems like quite a bit, eh?

And the difference between 50w and 75w is not a great as you might think. In a perfect world the difference would only be 1.75db....realistically it would be closer to a 1db difference in output.

All in all....your setup is fine as is.

Ok, so that leaves the rear pillar speakers. They are supposidly driven directly by the head unit, which puts out 4x18RMS I believe. They sound WAAAY quiet compared to everything else.

GOOD!

When the system is turned up to the point that the bass begins to hurt my wimpy ears, I have to put my ear directly on the speaker to even tell if it's playing.

You shouldn't be able to hear them anyways!

Honestly, it sounds like your installer did a pretty good job with the setup!

Did they bridge this power?

No.

Or if not, is 18W too little for these 40W speakers?

Not at all, especially for the rear speakers.

Your installer did exactly what most people with decent knowledge do....run the rear speakers off of the headunit so that they have very little output. You should not be able to hear them in the front seat at all, as this will ruin the systems imaging and soundstaging. They are, at most, to add some "fill" at lower volume levels for the rear passengers.

Now, to me, everything sounds good, but I'm left wondering:1) If I have the head unit turned about half-way of the volume control, how much power is being delivered? Half? Am I going to blow the sub if I turn the volume up 3/4 or something?

It's sort of a complicated subject, since there are factors that come into play such as the voltage output of your headunit and the gain setting of the amplifier. But, if the gain is set to a 1:1 ratio (you problably don't know if yours is or not, so don't freak out about it), with typical music content (since the music isn't 0db all the time, but typically averages around -6db to -10db depending on the music) the amplifier is probably outputting an average of around 10% of it's rated power. Depending on the gain setting, it could be outputting up to around 30% of it rated power on average, with only extremely brief musical peaks that last tenths of a second even approacing close to amplifier's rated power output.

2) The rear speakers are way too quiet compared to the other speakers. What can be done about this? Is it possible that the installers didn't provide enough power to these speakers? Hmmm

Leave it exactly how it is! Your installer did a good job!

3) Do I understand how the components are wired to the 2 channel correctly?

I hope you do now.

 

[tstein]

Thanks so much for the answers. You totally cleared everything up for me...very good explanations! I'll have to go buy my installer a beer.

I've got another noob question. Ok, so everybody has differnent musical tastes...who am I to question, but I see a lot of talk about 2000W+ crazy levels of bass in systems.

Now, my system is on the low end of the bass wattage being talked about in this forum. When I'm in the car listening to some music loud and I get out and close my door, the music is barely audible externally. To me, the music sounds really good...bass is tight...doesn't linger. The mids and highs are loud and everything together just sounds right.

Now, I've seen lots of cars roll by that their base is literally shaking other people's glass.

My questions are:

1) Is most of this "excessive" bass just part of the car audio hobby? Sort of like overclocking a PC and bragging about the extra 200Mhz?

2) Do some people really like the sound of the music with the bass literally turning their cars into a vibrator? Or is it just to show the ladies whats up?

3) My installer put dynamat (and dynosorb) in my doors. Is this probably the reason for my truck being mostly inaudible externally? Don't get me wrong...I don't want ppl knowing I'm bassing.

Next week I'll be heading back to this installer to put in a viper alarm. I'll be sure to thank him!

Tomas

 

[squeak9798 5,000+ posts]

My questions are:

1) Is most of this "excessive" bass just part of the car audio hobby? Sort of like overclocking a PC and bragging about the extra 200Mhz?

Yup. Some people, such as yourself, enjoy the bass to be nothing more than properly blended with the rest of the system. This is, really, how the subwoofer is supposed to be setup for someone interested primarily in sound quality.

Then you have the crowd, lovingly labeled "bassheads", who enjoy the bass being 30db+ louder than the rest of the system.

2) Do some people really like the sound of the music with the bass literally turning their cars into a vibrator? Or is it just to show the ladies whats up?

Some people do just enjoy feeling the bass rattling their eyeballs out of their sockets, while others do think it is going to impress the ladies.

3) My installer put dynamat (and dynosorb) in my doors. Is this probably the reason for my truck being mostly inaudible externally? Don't get me wrong...I don't want ppl knowing I'm bassing.

While having the dynamat and dynosorb are excellent products to be used in your sound system (+1 for your installer again), they are likely not the primary reason if they were only used around your speakers. It is more likely that your system is not heard outside the vehicle for the simple fact that you are running lower power levels. There simply is not enough output in your system to be heard much from a distance.

I personally think that's a good thing. You can play your stereo as loud as you want anytime and anywhere without having to worry about disturbing those around you. And it gets loud enough for you inside the vehicle, so you certainly aren't using a "lack of" power.