Holy misinformation batman!

[Ryan from Ohio]

And I quote:

To be honest it depends on what Subs your after as to what Size type of Amp to go for to drive them Confused

12" Subs are miles better than 10" ones and are much more efficient ( read as will be louder on the same size Amp ). Also manufacturers spend more time and effort developing the 12s as these are the mainstay of the Sub market.

When buying a Sub one of the most important things to look for is Efficiency Confused Not Power weather measured in RMS or whatever.

A fairly efficient speaker is rated at around 90 dB measured using 1 watt of power at a distance of 1 meter. All speakers are measured this way Wink

A speaker rated at 90 dB will go so loud. If you put a speaker rated at 93 dB on the same Amp at the same volume setting it will be physically twice as loud Shocked One rated at 96 will be 4 times louder than the 90 Cool and one rated at 87 will only be half as loud Sad

The RMS of a driver ( Root Mean Square, press 2 then 1/x then square root on your calculator to get the RMS value ) represents how much Power the driver will dissipate before it erm burns out.

So a Sub of 90 dB rated at 300 watts RMS driven at 300 Watts will only be as loud as a Sub of 93 dB driven at only 150 watts.

Ps you are more likely to damage a Sub with an Amplifier which is too small rather than one which is enormous Shocked

If you go for High efficiency components they can be driven from a head unit quite easily but will obviously sound better with their own amp when funds allow.

I paretically rate the Alpine Type R 12" Subs for an all round package say a pair of these driven by a Big Alpine V12 Amp. A friend of mine has a pair of these and the Amp in his Corsa and they sound Superb. Wink

The Focal Pollyglass Components he has are also Mint for the Dosh Wink

I always Go for Separate Sub Amps and front channel Amps because with multi channel amps they use a common internal powersupply, so when cranked right up the Sub section pulls most of the current from the Dc to Dc convertor which will drop the seccondary voltage rails which will make the other channels ( probably the fronts ) start to sound harsh.

So id go for a Mono Sub Amp and a nice two or 4 channel Amp for the rest.

Also when buying the Sub Amp a Mono Sub Amp will run at a 2 Ohm load so will drive two subs with 4 ohm voice coils. A 2 channel Amp bridged will only run in Bridge mode at 4 ohms so wont like it when ya put two 4 ohm drivers on its output ( which is 2 ohms ).

The more drivers you add together the lower the Impedance ( ohms ) will go. two 4 ohm ones gives 2 ohm and two 3 ohm ones will give 1.5, you get the idea Wink .

Also class D amps are good for driving Subs but sound shiite running fronts wheras class B,C etc sound good on them all but wont give ya as much power for the cash as class D.

So Class D monoblock Sub amp and a boggo normal amp for the fronts me thinks Wink ( Unless your a Millionair like Stu Very Happy )

So there :nana

I guess this guy has a fair amount of respect on the board this was posted at, which is a uk based board.

I ripped into him fairly decent, but didnt fully humiliate him...

My post, Im in bold...

To be honest it depends on what Subs your after as to what Size type of Amp to go for to drive them Confused

12" Subs are miles better than 10" ones and are much more efficient ( read as will be louder on the same size Amp ). Also manufacturers spend more time and effort developing the 12s as these are the mainstay of the Sub market.

I totally disagree with this. Who many people do you know in the industry? Have any of them told you this? Usually they develop the subs in a 12" or 15" prototype model, use the same motor and just change out the basket/cones. Ive seen this on numerous occasions from numerous manufacturers.I guess I disagree within the context its been used. TO believe its all just optimized for one isnt quite an accurate comment.

When buying a Sub one of the most important things to look for is Efficiency Confused Not Power weather measured in RMS or whatever.

Now this here is a total myth in the highest regaurd. So you think you can judge how louyd a speaker can get overall just by its characteristics when given 1 watt? This is inconclusive right off the bat. It doesnt even consider themral properties of the coil not to mention impedance rise and the such. Furthermore how do you know what terms the manufacturer uses to set this number? With what mic? Calibrated how often? Averaged over how many units? With what sounc? Music? pink noise? tones? A, b or c weighted scale? There is way to many factors here to try and cliam which one will be louder based off this pretty much useless number... Furthermore I have seen plenty of subs with a low arse efficency stomp out plenty others... useless number Im telling you all...

A fairly efficient speaker is rated at around 90 dB measured using 1 watt of power at a distance of 1 meter. All speakers are measured this way Wink

A speaker rated at 90 dB will go so loud. If you put a speaker rated at 93 dB on the same Amp at the same volume setting it will be physically twice as loud Shocked One rated at 96 will be 4 times louder than the 90 Cool and one rated at 87 will only be half as loud Sad

Again tis is totally false. You cant possibly even begin to claim whats in the previous paragraph. If you truly believe this I have to truly question your car stereo knowledge... sad

The RMS of a driver ( Root Mean Square, press 2 then 1/x then square root on your calculator to get the RMS value ) represents how much Power the driver will dissipate before it erm burns out.

So a Sub of 90 dB rated at 300 watts RMS driven at 300 Watts will only be as loud as a Sub of 93 dB driven at only 150 watts.

Hold the phones here. The more I read of this post the more I doubt you sir. This here is the most inaccurate piece of guessing Ive seen to date. THis is totally false and completely absurd. Heres a good sight for you to read up on: www.bcae1.com . If you got some legitimate proof on this Im willing to listen. There is absolutely no way on this earth can you make that claim, none... goosh...


Ps you are more likely to damage a Sub with an Amplifier which is too small rather than one which is enormous Shocked

Again this is an open ended myth. This is FALSE FALSE FALSE FALSE. You want to damage a sub with an amp? fine exceed the thermal rating power? How do you do that? TO BIG OF AN AMP. -or- clip the piss out of it sending it straight DC voltage. Thats how you damage a subs coils, and thats the only ways you can. This is fact. Not giving it full power will NOT damage a sub... Remember the RMS ratings are usually lower than what a sub can actually take. Each sub is individual and so are its breakign points...

If you go for High efficiency components they can be driven from a head unit quite easily but will obviously sound better with their own amp when funds allow.

You seem to place a lot of faith in an invalid number my friend. Fact: head unit power is dirty power. So you factory head unit puts out say about 20 WRMS. Now put in a small 20 WRMS amp. Im willing to bet that the one with an amp will sound 250% better. Efficency has no room in this topic, period. The simple fact as stated earlier is the headunits lack of clean amplified signal. Heck you can even run a cheap ass amplifier and it will still sound 250% better providing it has equalizer functions for proper tuning...

I paretically rate the Alpine Type R 12" Subs for an all round package say a pair of these driven by a Big Alpine V12 Amp. A friend of mine has a pair of these and the Amp in his Corsa and they sound Superb. Wink

The Type R's are a truly decent all around sub. Many street beaters like them as they sound ok and can get hella loud. I actually know a guy with a single 12" Type R hitting a consistent 154 dB... oh ya bringing the pain! By all means though its not an SQ sub, not even close...

The Focal Pollyglass Components he has are also Mint for the Dosh Wink

Focal makes some killer products. But as anyone knows if the install sucks, the system will also...

I always Go for Separate Sub Amps and front channel Amps because with multi channel amps they use a common internal powersupply, so when cranked right up the Sub section pulls most of the current from the Dc to Dc convertor which will drop the seccondary voltage rails which will make the other channels ( probably the fronts ) start to sound harsh.

The only concieveable way this can be true is with a 4 channel amp. If you have a 5 channel amp of the sort these factors are engineered into the design Wink

So id go for a Mono Sub Amp and a nice two or 4 channel Amp for the rest.

finally some good advice!

Also when buying the Sub Amp a Mono Sub Amp will run at a 2 Ohm load so will drive two subs with 4 ohm voice coils. A 2 channel Amp bridged will only run in Bridge mode at 4 ohms so wont like it when ya put two 4 ohm drivers on its output ( which is 2 ohms ).

THis is not necessarily accurate. It depends on the amp. I had a 2 channel amp I could take down to 1 Ohm and was rated for it. I have seen others that can go down to .25 Ohm.

The more drivers you add together the lower the Impedance ( ohms ) will go. two 4 ohm ones gives 2 ohm and two 3 ohm ones will give 1.5, you get the idea Wink .

It depends on how its wired. Sure if you are putting everythign in parallel. But if you series everythign the Ohm will go higher... What about when you get into series/parallel mixes? Wink

Also class D amps are good for driving Subs but sound shiite running fronts wheras class B,C etc sound good on them all but wont give ya as much power for the cash as class D.

Class c? lol Ok thats a new one to me, honestly. If there is a class C amp point me to it. Ive been doing this for over 10 years and have yet to hear of a Class C. Ive heard A.b.a/b,D,T and X...

When we are talking sub duties there is no audible difference between a Class D or A/B. Sound quality is all in the ear of the beholder. But from the collective knowledge between about 6 forums and probably 20K users almost all will agree in the sub stages there is no audible or so little its almost inaudible...

Amps if rated correctly will put out power within its area. A Class D amp @ 100 WRMS wont put out more power than a Class A/B @ 100WRMS simply because ones is a Class D and the other A/B. A Class D however is more efficent than an A/B, so it will require less amperage to make the same power as an A/B.

So Class D monoblock Sub amp and a boggo normal amp for the fronts me thinks Wink ( Unless your a Millionair like Stu Very Happy )

So there :nana

So to sum it up there is a lot of myths and misinformation in your post. If you care to back anything said up with clear scientific proof so be it. If anyone would like to argue any of these myths please go for it. Wink I know I am fairly new here but Stu can give words on my Car Audio knowledge. If anyone cares to question it I got approaching 10K worth of testimonials here on my board: www.caraudiocentral.net

This guy is a complete ass... We will have to see how he likes taking the information boner up his hershey highway....

[OnYrMrk]

wow...actually, you are wrong, and so is he...Focal Poly Kevlars are made for the dash, just check out my install...LMAO

j/k Ryan...

[High Society]

you the man Ryan

[Darthness]

ryan dude, you're giong to get ripped hard by less educated folks.. mroe than likely.

especially if you're new there and he's been there for a while. :P (i know all about that )

[William from NOLA]

It was nice knowing you Ryan. I hope you don't get another stalker lol!

[Darthness]

lol, so if a sub that hits 137 and has 90dB efficiency, a sub with 93dB effiencey will easily hit 274dB? kickass.

[Ryan from Ohio]

lol, looks like you need to learn about dB and perception of sound darth

Well the guy is from the UK so Im not worried about a stalker.

Also I know a few people from another board Im on thats over at that one, so I got backup.

Lastly if they want to argue the facts so be it, they will get owned in front of their peers then

[GlassWolf]

To quote Ron White, "You can't fix stupid."

[Bwcad1]

heres your sign.

[CaptainPioneer]

"I pulled into a gas station when i had a flat tire and i swear the gas attendent said "Tire go flat?" I couldnt resist... Nope the other 3 just swelled right on up on me.... Here's your sign! lol"