Info on Car Audio

[RtN]

http://www.kenwoodaudio.com/australi...&Model=KAC-X40

800W @ 4 channel! LOL but yeh i think i get it now.. 200W per channel!

thanks guys

[arverson]

kenwoods own site says its not even half of 200 per chan..

i think something that would help you in car audio is DO NOT LOOK at max/peak power ratings. look at rms/nominal/continuous ratings

and.. for $699 you can get something so much better, but its up to you

[OMG.JAI xD]

lol .. check out ebays brutha.

4 channel 5000 watts!!! (PMPO) LOL

mate .. my soundstream monos only produce 2000watts @ 1 ohm rms .. and tht costed 1 grand ish . .retail.

sif get 5000 watts for a few hundred bux .. psahh!


just be on the look out that most sellers out there try to sell theyre products using PMPO ratings.
which basically, i think, derived from chinese manufacturers thinking they can put the principal of a normal speaker which has an RMS and peak rating.
which CANNOT , be applied to an amp.

an amp is the power source, to be on the general side, and cannot have a constant power output at variable rates. unless diferent ohmages (if thats a word) is applied.

btw.. PMPO is supposedly .. peak music power output.
which some how...is equivalent to 10 times of the rms.

RMS is root mean square.
its the formula used to rate, or give, to a electronical device that produces an always variable output.
in this case, different frequencies will take different amounts of watts to produce.

lol i tried to understand rms ... but it didnt really help LOL.
all i know is, theres a test involved with it, and ends up giving a precise rating. =]

however, with speakers .. you have to look at both RMS and peak.
its basically a minimum and maximum sorta thing.
rms is the recommended .. and anything in between up to peak. should, be safe...or fine..

theres alot to audio.
alot to learn.
but its interesting.



off topic. but to all those that find electrical stuffs interesting.
go look up perepertia generator or prepertiria generator or some shet like that.
its pretty interesting.
apparantly some white dood in americano figured out a way of eliminating the back emf created by an induced motor. and using that emf to turn a rotor that runs to the induced motor.
so .. liek a cycle sorta thing.
so.. basically... its creating energy.. simply by magnets .. =]

pretty coolio i reckons.

have fun =]

[tron07]

http://www.kenwoodaudio.com/australi...&Model=KAC-X40

800W @ 4 channel! LOL but yeh i think i get it now.. 200W per channel!

thanks guys

its 200w probably at 2 ohm or 400w X 2 bridged.... you probably wouldnt be using it this way cause the THD is very high.... You can get away by using it for sub as you cant really hear the THD if its just slightly higher then the rated.... then again there are always execptions....

power is not always tell you the whole truth... I would prefer 25w RMS from a good Class A powering my comps then a noisy 200w from a el-cheapo amp.

[tron07]

lol .. check out ebays brutha.

4 channel 5000 watts!!! (PMPO) LOL

mate .. my soundstream monos only produce 2000watts @ 1 ohm rms .. and tht costed 1 grand ish . .retail.

sif get 5000 watts for a few hundred bux .. psahh!


just be on the look out that most sellers out there try to sell theyre products using PMPO ratings.
which basically, i think, derived from chinese manufacturers thinking they can put the principal of a normal speaker which has an RMS and peak rating.
which CANNOT , be applied to an amp.

an amp is the power source, to be on the general side, and cannot have a constant power output at variable rates. unless diferent ohmages (if thats a word) is applied.

btw.. PMPO is supposedly .. peak music power output.
which some how...is equivalent to 10 times of the rms.

RMS is root mean square.
its the formula used to rate, or give, to a electronical device that produces an always variable output.
in this case, different frequencies will take different amounts of watts to produce.

lol i tried to understand rms ... but it didnt really help LOL.
all i know is, theres a test involved with it, and ends up giving a precise rating. =]

however, with speakers .. you have to look at both RMS and peak.
its basically a minimum and maximum sorta thing.
rms is the recommended .. and anything in between up to peak. should, be safe...or fine..

theres alot to audio.
alot to learn.
but its interesting.



off topic. but to all those that find electrical stuffs interesting.
go look up perepertia generator or prepertiria generator or some shet like that.
its pretty interesting.
apparantly some white dood in americano figured out a way of eliminating the back emf created by an induced motor. and using that emf to turn a rotor that runs to the induced motor.
so .. liek a cycle sorta thing.
so.. basically... its creating energy.. simply by magnets .. =]

pretty coolio i reckons.

have fun =]

lol..... I acctually dont understand what you wrote....

[RtN]

Hmm now onto a new topic =]!!

RCA Pre outs!
So basically if you have 2 pairs of RCA = more control over your speakers?
and 3 Pairs of RCA = even more control?

But we need to buy an amp to support 2 or 3 rca's respectively right?

[tron07]

+rep me, then I will dig or post some stuffs about RCAs.

[Vinnie]

lol you cant hold info hostage for pq points

rca's pre-outs on their own do not enhance the sound or give you more control, they are merely used to connect your amps to the h/u. hence, a h/u with at least a couple of good voltage (eg. 4v) pre-outs is a wise investment.

and i think what jai was trying to say is be wary of the large power ratings printed on some cheaper amps as they are not an accurate indication of how good the amp is

[dahon]

rca pre-outs are basically the raw signals that come from you headunit. they arent amplified by your headunit at all, thus the 'pre' term. with these preouts you connect to your power amplifier to boost, process and amplify the signal. thus if you have an awesome amp then you gain a better amplified signal when you compare a speaker level output (signal was processed by headunit) + power amp combo.

ALWAYS look at the RMS rating of amplifiers. DO NOT look at those 1000w figures... these figures are what they get in the laboratory during controlled tests and by the time your speaker/amp combo hits half of that figure it will have cracked. they are a marketing gimmick to try and get your attention.

try to match your amplifiers RMS output with your speakers RMS capacity, as these will get you good enough results. Depending on the amplifier you may be able to drive a higher rated speaker, ie 50w amp driving 80w rms speaker, but mostly these are the good branded ones. for example my home theatre stereo power amp only puts out 100w RMS for each channel and it drives a pair of b&ws rated at 150W RMS.
you also have to look at the inductance? (is that wat its called) of the speakers and amps, ie the 4ohms and so forth. the lower the number, the harder the amplifier has to work to drive the said speaker. normally i would recommend you stick with 4 and 8 ohm systems.

also some h/u's offer a sub preout, and these connect to your monoblock amp, allowing you to buy a dedicated amp without the low pass filter as the h/u does the work. so look around for your options.
-if you want to power subs i would recommend looking for amplifiers with the low pass filter, as these filter out the bass notes.
-for splits (driver + tweeter combo), look for crossovers or inbuilt mid/high filters in the amplifier aswell to seperate the midrange & highs.

tip1: DEFINATELY INVEST IN A GOOD AMP. you can always get a decent speaker/average speaker. its the amp that does most of the work processing the signal.

[tron07]

lol you cant hold info hostage for pq points

Do you know there are so many configuration you can play with RCAs... even with one RCA preout, you can split it with line driver, external crossovers, etc... and different HU with different specs, etc... then there is signal matching... just too much to write.....



Since the original thread is about amp, here are what some info on what the specifications on the amp means.....

Frequency response refers to the range of frequencies which the amplifier can reproduce within a certain power range, usually +/-3dB.

Continuous power output is the power output of the amplifier into one channel into a certain load (usually four ohms) below a certain distortion level (usually at most 1&#37;THD) at a certain frequency (usually 1kHz). A complete power specification should include all of this information, e.g. "20W/ch into 4 ohms at < 0.03%THD at 1kHz" although this can also be stated as (and be assumed equivalent to) "20W/ch at < 0.03%THD". The amplifier should also be able to sustain this power level for long periods of time without difficulties such as overheating.

Peak power output is the power output of the amplifier into one channel into a certain load (usually four ohms) below a certain distortion level (usually much higher than the continuous rating level) at a certain frequency (usually 1kHz). A complete power specification should include all of this information, e.g. "35W/ch into 4 ohms at < 10.0%THD at 1kHz" although this can also be stated as (and be assumed equivalent to) "35Wch at < 10.0%THD". Consumer warning: some manufacturers will state the "peak power output" rating by including the amount of power which can be drawn from "headroom", which means power supply capacitors. They usually will not tell you this in the specification, however; indeed, they tend to prominently display the figure in big, bold letters on the front of the box, such as "MAXIMUM 200W PER CHANNEL!!!" when the continuous rating is 15W/ch and the unit has a 5A fuse.

Damping factor represents the ratio of the load being driven (that is, the speaker - usually four ohms) to the output impedance of the amplifier (that is, the output impedance of the transistors which drive the speakers). The lower the output impedance, the higher the damping factor. Higher damping factors indicate a greater ability to help control the motion of the cone of the speaker which is being driven. When this motion is tightly controlled, a greater transient response is evident in the system, which most people refer to as a "tight" or "crisp" sound. Damping factors above 100 are generally regarded as good.

Signal to Noise Ratio or S/N Ratio is the ratio, usually expressed in decibels, of the amount of true amplified output of the amplifier to the amount of extraneous noise injected into the signal. S/N ratios above 90 to 95dB are generally regarded as good.


As my personal experience...... I do believe different amp has different characteristic.

Specification is one thing, the sound of the amplifier is another thing. @ different brand of amps with similar specs usually sounds different. Good brands usually under spec their product on paper, so you will get better sound/power then what is stated, while el-cheapo stuffs usually overstate/overspec to lure in unsuspecting buyers. However if you do a Richard Clarke test, then the amp will sounds the same, as you strip away all the stuffs that make them sound different.

Then there is also amplifier class, but that another thing for another day.....

[arverson]

lolz are we all helping you rtn or are we confusing u even more?? :P

if its within your budget, try and get a head unit with 3 preouts. and dont worry if its 2, 4 or 8v preouts.. a 2v should be more than sufficient for you.

[RtN]

Thanks arverson ahaha im kinda lost.. but yeh..

Umm I am going to have 2x 12"subs i believe and 220w fronts and pioneer tweeters and dunno about the 6x9" at the back.. ( All Pioneer )

So this set up would require 2 amps right? a 2 channel for the Subs and a 2 or 4 channel for speakers.. Or I could get a 4 channel.. 1 for each sub. and 4 speakers to the 2 remaining channels right?