Need suggestion on subwoofer

[kyheng]

How much is the bass blocker cost? As I normally use a capacitor to reduce the bass from Hu to speakers. Anyway stock speakers from Proton cars is around 20-30w rms.

 

[SPocn]

kyheng @
ya i know its old model but i wont mind if it is new and good quality ^^. wow you bought it so cheap, they all now bid till over rm300+ at least. :/ hard to get them cheap anymore i guess.
Btw how is a/d/s 236 6.5" Component Speakers quality compared to this RF model? i mean how far their quality would be differ? saw it from yohannes's selling thread. quite attractive >.
bububann,Zenn @
:/ i think i would try to get those new one and wont need to drive at 1 ohm. ^^'' hope to get one that can last for many years
n that seller seems want to get a fast deal b4 this saturday. Seems like i cant get it from him also (still saving money)
and is the enclosure you mean=the box?

Kippo @
^^ yeah bro, kicker is now in my list of choice also. :/ i'm too greedy to want both spl and sq(hehe i guess better go for sq, since many SPL player seems would change to SQ after long playing)
hmm btw what is IMHO and Fs mean ? i always see these few words but still cant figure out what it means ??

cacin,kyheng @
Hmm so is better suggested to change the HU and speaker all together so they wont burn so easily in long run?
wow bro cacin, that seems a bit complicated for me to understand ^^'' (sorry i really new to ICe)
:/ i thought capacitor only used to provide smooth voltage

 

[kyheng]

So far I know the RF I bought is ori, don't know other brand how is it. For 300 is not bad the quality.
The big capacitor that cost rm400-500 is for voltage, the small ones 0.5-1 I use it for reduce the bass. The most simple passive crossover.
Hu you can keep it first then upgrade later, ask you to do once sure you will KO.... If you can add the small cap then you can turn the volume abit higher to compensate with your sub's bass. Box calculation you no need to bother so much. Like me just get a ported one then less headache as 12" sub the box standard size more or less the same. Sealed one if not mistaken have to follow the sub's spec.

 

[Kippo]

Kippo @
^^ yeah bro, kicker is now in my list of choice also. :/ i'm too greedy to want both spl and sq(hehe i guess better go for sq, since many SPL player seems would change to SQ after long playing)
hmm btw what is IMHO and Fs mean ? i always see these few words but still cant figure out what it means ??

then u need to spend more since SQ subs are not cheap.

IMHO = In My Humble Opinion

Fs = resonance freq.

 

[cacin]

as promised, here is the table for frequency distribution of power in music

frequency Maximum power above that frequency
300Hz 50%
600Hz 25%
1200Hz 10%
2400Hz 5%

Bass blockers are also known as capacitors :regular_smile:
Which part you don't understand?
let me rephrase: The sub amp power should equal 1.5 times the power to the front speakers.

IMHO = in my humble opinion
Fs = resonant frequency of driver (speaker) this is one of the Thiele/small parameter of a speaker (driver). These parameters are very very useful if you really want to design a box that best suit your subwoofer.

Since you say you're a newbie, why don't you go to www.bcae1.com. They have a lot of things to learn :_:

 

[Kippo]

as promised, here is the table for frequency distribution of power in music

frequency Maximum power above that frequency
300Hz 50%
600Hz 25%
1200Hz 10%
2400Hz 5%

i dont understand what u mean by max. power above that freq.

 

[Kippo]

spocn,
maybe u r interested in this http://www.gr8tunes.net/forum/showthread.php?t=6494

 

[cacin]

Ok, this comes from the car stereo cookbook second edition.

"
How Much Power Do you need?

The appropriate power for a subwoofer amp mainly depends on how much power is used for the rest of the system and the subwoofer crossover frequency used. The typical frequency distribution of power in music is shown in the table.
Notice that less than half the power in music is above 300Hz. This means that at least half the power in music is below 300Hz. To make sure you're covered, use the following rule of thumb: the sub amp power should equal 1.5 times the power to the front speakers.
This rule is quite generous with power to the sub for typical situations, but not all situations are typical. Consider using more power for your sub amp if
1. your sub X-Over frequency is higher than 150Hz
2. your sub sensitivity is exceptionally low.
3. your sub is installed in a trunk that is sonically isolated from the passenger compartment.
4. you like music with lots of deep bass. "

pheww.....

 

[Kippo]

hmmm... why it explains that way..... hmmm...

why dont make it simple like ...

1. To play lower freq. louder, u need more displacement. To get more displacement, u need bigger cone which has more mass. Since it is heavy, u need strong motor which need more power. So to play low freq., u need more power.

The point no. 1 to 4 is moot. That is what u expect if u do that no.1 to 4.

 

[Zenn]

as much as i respect the author for that book i think his views are too simplistic/general, how much power we need depends on the power handling of the sub u have, or what type of sub u get depends on how much power your amp can give out and/or depend on how its wired (at hoe many ohms)

if i get 50W stereo amp for my components, i need a 150W for my sub right? but if im using alpine type X sub which is 1000W rms, 150W amp mana cukup...correct?

 

[cacin]

Zenn,
Ok, I do not have any connection to the author, but i just want to point out a different view on this matter.
Probably, the way he's looking at it is, how much sub power do i need? So, based on the answer, it's logical right? But, if you already had a sub, then, of course you need to select an amp that's suitable for it right?

Probably, the way he design the system is based on the front speakers amp. So, if front is provided with 50W RMS each channel, then it would make out that you will need a 150W RMS sub to compliment that system (based on the formula).

Kippo,
I can only say for point 2.
Lets say you have a sub A with 90db sensitivity, playing at 100W.
If there is another sub B with sensitivity at 87db, the sub need more power to play as loud as sub A. So, the power req for sub B is more than 100W. If you have a sub C that has a 93db sensitivity, to play as loud as sub A, it just need lees than 100W of power. So, statement no 2 is still valid right? However, you still need to take into accout about bass response of the subs.

 

[Kippo]

Kippo,
I can only say for point 2.
Lets say you have a sub A with 90db sensitivity, playing at 100W.
If there is another sub B with sensitivity at 87db, the sub need more power to play as loud as sub A. So, the power req for sub B is more than 100W. If you have a sub C that has a 93db sensitivity, to play as loud as sub A, it just need lees than 100W of power. So, statement no 2 is still valid right? However, you still need to take into accout about bass response of the subs.

when it comes to subwoofer, sensitivity number is useless once the subwoofer is in the box.
Go plot in WinISD and see for ur self. Take any subs with different sensitivity, key in the same amount of power and see the transfer function curve.
To have apple to apple comparison, all subs that u compared must have the same Qtc (alignment).

 

[cacin]

Hi Zenn,
Thanks for that info. Didn't know about that. :)

 

[SPocn]

kyheng@
hehe yeah i think i would just get that ported box.

kippo@
Awww, then i better stay for SPL i guess :(
:/ that seller seems prefer to COD at SS so i think i cant get it atm since my money isnt ready yet also
anyway what is the marketprice for that kicker solobaric? Might consider get a new one at my place once i got the money
would that solobaric better than 2 12" sub?

cacin@
@@ i sux at maths. TY for the website, gonna study more before getting them >.<

 

[Zenn]

Hi Zenn,
Thanks for that info. Didn't know about that. :)

aik...which info is this??

hehe anyways.....the funny thing about the 50W fronts and 150W for sub is that.......i have a system exactly like that in my other car, hehehehe.....how ironic :shades_smile:

 

[cacin]

when it comes to subwoofer, sensitivity number is useless once the subwoofer is in the box.
Go plot in WinISD and see for ur self. Take any subs with different sensitivity, key in the same amount of power and see the transfer function curve.
To have apple to apple comparison, all subs that u compared must have the same Qtc (alignment).

Kippo,
I was thanking you for this info. Maybe I need to read more...:_:

 

[TT9236]

kyheng@
hehe yeah i think i would just get that ported box.

kippo@
Awww, then i better stay for SPL i guess :(
:/ that seller seems prefer to COD at SS so i think i cant get it atm since my money isnt ready yet also
anyway what is the marketprice for that kicker solobaric? Might consider get a new one at my place once i got the money
would that solobaric better than 2 12" sub?

cacin@
@@ i sux at maths. TY for the website, gonna study more before getting them >.quote]





so u get your sub already???
how about install 3 sub to get 1.3 ohm ??
not so hot for your amp and no need to upgrade ur alternator or bty too

 

[Performance Werkz]

SPocn,
I have a Brand New Kicker L5 12" SUBWOOFER for sale

600W PEAK POWER
600W RMS
DUAL 4
WIRE TO A 2 OR 8 OHM LOAD

PM me if interested. Hopefully will be below 1k. Dont really know the price now for one of this subs.

 

[SPocn]

TT9236@
:/ never thought of getting 3 subs and i dont know all those calculation how to get that value of ohm also xD (i'm really newbie and confuse with those maths calculation) Btw my budget would increase if i get 3 subs

Performance Werkz@
:D ty for the infor, i haven decided which brand of sub to buy yet.(money haven ready yet) i would pm you if i'm ready to get them thanks

 

[Kippo]

so u get your sub already???
how about install 3 sub to get 1.3 ohm ??
not so hot for your amp and no need to upgrade ur alternator or bty too

generally it is seldom ppl use 3 subs due to the impedence load it presented to the amp.

IMHO there is no issue of loading the amp to 1 ohm if it is been designed for it. Also if it is getting hot, no issue in this as long as u don't get amp shutdown.
Generally if the amp shutdown due to running 'hot' then it is due to user pushing the amp more than what it is designed for. Also on the installation eg. kept in areas with minimal cooling air circulation like under the seat, under carpet, hidden somewhere where no air flow etc.

I run my amp at 1 ohm and i don't have issues with amp problem & power issue since music does not load the amp 100% all the time.
U have to realise that for 1000w amp, it does not output 1000w all the time. It is only when the music requires it and it will not be continous.

I believe most ppl blast their sub when parked and alternator does not produced full rated power at idling rpm. To resolve this parking blasting, u need bigger battery or adding second battery with required isolation.