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Discussion Starter #1
ok seen alot of you talking about your 1000w subs and 900w 6x9's it all sounds great but in reality they are far from what it says on the tin

these r the amps/speakers MAX ratings now on a speaker the max rating is the max power it'll take but when u start putting the max power into em they can distort

and for amps well an amp will very rarely output its MAX power figure i.e 1000w n when it does its only for a milisecond or 2

so how do u work out how much power your amplifier is putting out? or whats the best amount of power for the speaker?

well the speaker calculation is rather complex so general rule of thub is the RMS (root mean square) or nominal power it is most efficent or works best with is usualy about half the quoted max power same sorta rule can be applied to an amp

now if you wanna work out more exact what the output is heres the calculation..

VxAxE

V= voltage
A = amperage (fuse rating what current the amp draws ie 20amp0
E = efficency (different for all types of amps general Class D or monoblock amps r 70-80% efficent and Class A or B are between 50 and 60% True Class A is about 90% but theres hardly any Pure Class A amps out there n the ones that are are a few grand)

so for example lets take a 1000w MAX rated amp with a 40amp fuse which is a monoblock (Class D)

ok Volatge when a car running is 13.8v 99/100
amperage well it has a 40 amp fuse so this is 40
efficency we know class D's r roughly 70% efficent so this is 0.7 as 100% = 1

so..

13.8 x 40 x 0.7 = 386.4 so lets call it 385 this is our RMS (root mean square or nominal power output) that the amp puts out

so as you can see it doesnt really matter what it says on the box its more what fuse is in it/what current it draws

but then again most amps will not draw the full amount of current which the fuse is rated at or it would constantly pop, so we can give this a 5-10% leaniancy so in our above example would actually be 36-38 amps therefor...

13.8 x 36 x 0.7 = 347.76 lets round it down to 345

thats a 1000w amplifier that only actually puts out 345 watt

now lets do a 2 channel amplifier which is Class B..

quoted 400w x 2 MAX and has a 40amp fuse rating

now from our above equation we know about the current leniancy we have to take into account which in this case again would be 36amp and efficeny is 60% so 0.6 for E

so

13.8 x 36 x 0.6 = 298.08 now lets round this one up slightly just to make things simpler so 300w

now we have 2 channels so simply divide by 2 which would be 150wrms x 2

now for the best sounding system posiible you really want to be matching the RMS values of the amps to the speakers and as stated above if you cant find the RMS value for the speaker half the max rating which will give u a rating slightly higher than the rms but match this and the speaer should perform at its most efficent

i could go on alllllll day about amps speakers and setting a system up properly but the average joe doesnt need to know all this however i feel that people like to get the most out of thier equipment so when your using a set of 200wrms speakers and the amp is only giving them 20wrms theres quite a bit going to waste!

if you feel theres anything iv missed please feel free to tel me or if u think ive done something wrong please correct me and i hope this helps people in future when choosing an amp and speakers....
 

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Discussion Starter #3
well i could rant all day bout QTS and other bollox u lot wouldnt understand but im kind i dont :p


btw if theres someting u dont get just ask
 

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simple way to look at it ...

if your buying decent makes they normally show the power rating in RMS ... the higher the rms the better the speaker ..


if its got a high max watt u betta check the rms cos if the rms is shit then i would have to say the speaker will probs be shit.
 

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Nitro advise then please

Ive got all JL Gear

e6450 6 channel amp

2 sets vr components
1 set tr 6x9s ( only get used at cruises etc so dont start lol)

1800d Mono Block amp
2 12" w3 Subs Dual Voice coil running at 2 ohms.

Is that all matched up pretty well???

Maddsy
 

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Monkey Magic said:
simple way to look at it ...

if your buying decent makes they normally show the power rating in RMS ... the higher the rms the better the speaker ..


if its got a high max watt u betta check the rms cos if the rms is shit then i would have to say the speaker will probs be shit.
=D> =D> =D>

Its not make by Ronseal so dont always believe everything you read on the tin ( box )
 

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Discussion Starter #7
Monkey Magic said:
simple way to look at it ...

if your buying decent makes they normally show the power rating in RMS ... the higher the rms the better the speaker ..


if its got a high max watt u betta check the rms cos if the rms is shit then i would have to say the speaker will probs be shit.
wrong wrong wrong :p wel your on the right track sorta but not quite entirely right, because 1 speaker has a better RMS than another doesnt make it better than the other, for instance my old rainbow would wipe the deck with just about any 500-600wrms (bar JL/IDMAX) n that was only 400wrms

as for you mr maddox, ill tell ya when ya pop on msn:p or if u post rms values for me ill say if its matched power wise
 

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nitr0genics said:
well i could rant all day bout QTS and other bollox u lot wouldnt understand but im kind i dont :p


btw if theres someting u dont get just ask
Yeah lets talk Qs :lol:

:guns:

Next thing How to build a bandpass box and it to 33hz then get your missus to sit on it :wohow:

Gen you are starting to loose me!
 

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Or pay someone to do it!!

I am going to be building an enclosure for my MW12 in the next few weeks when I get some spare time however I need to work out just how much volume I have with all the curves I plan

Having only ever done kick pods b4 I am not 100%

I could build it and add lumps of wood but not too keen on this

Any ideas? I thought about using water but thats a lot of water!!!
 

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Discussion Starter #13
run it in an AP or summin, build round that think easiest way would be measure an internal box shape calculate that volume then estimate the rest, but if its got to be spot on your gonna have to use water or something im not quite sure tbh mate box it and build round it or maybe vent it into boot floor
 

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Okay I have a couple of ideas

I wish I had MSN

P.S. my ps2 went boom! Know anyone who knows how to fix? If just says "cannot read disk" all the bloody time!

If its fecked a new ps2 for me so i will get 2 slim ones (One car one house)

PPS Still thinking about screens mate!
 

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Discussion Starter #15
slim ones dont work on slot load like the big ones though so it'd have to be glvoe box or custom dash jobby for it,

might just need a new laser unit TBh
 

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how much for laser, anyone know?

plus nayone know how to fit it?

Of am I better off spending £100

BTW its going in the glove box :))
 

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Discussion Starter #17
better off spendin 100 notes mate new slimlines r slightly bigger than a dvd case n same thickness, i bought mine n was ready to take it back when i opened the box tiny as hell
 

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But the problem is also finding some! Amazon has run out so has my local currys

Going to try GAME tonight then might get desperate and go for argos or something

If it is that small I might put it underneath the dash and build a cover for it will see

got some leather that needs usin up :)
 

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muz, use measuring jug filled with polystyrene ball's (like bean bag stuff!)
Thats a very good indication of what volume the area is you are using, and you can hoover them up afterwards!
dont forget put it in 1l at a time
 
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