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General => Car audio => Topic started by: Shady Pioneer on 05 April 2008, 15:11

Title: Connecting sub to amp...
Post by: Shady Pioneer on 05 April 2008, 15:11
Does the sub get it's power from the amp it's connected to?

So if I buy a 4 channel amp, split it 3 ways (2 front speakers + 1 sub), all I have to do it connect the sub to the amp and no more wiring for the sub?
Title: Re: Connecting sub to amp...
Post by: S11EPS on 05 April 2008, 20:34
A subwoofer is no different to any other speaker, it is just optimised for playing low notes.
Therefore it doesn't need 'power', just a signal, exactly the same as any other speaker.
So, wire up your amplifier with a permanent live, quality earth and remote (to switch the amp on and off) and then connect your speakers (including the subwoofer) in the normal fashion.
I'll happily draw you a wiring diagram if you need it - any help you need, give me a shout
Title: Re: Connecting sub to amp...
Post by: dan23 on 05 April 2008, 21:27
heres a diagram for you

(http://i200.photobucket.com/albums/aa91/dpenniall1984/ampwirediagram.jpg)
Title: Re: Connecting sub to amp...
Post by: boneybradley on 05 April 2008, 22:53
The only problem i can see is unless you can seperate the signals the sub will get high notes like the fronts... i would get a small 2 way amp for the fronts and another for the sub.. mine uses a 2x50w rms for the fronts and a 1x400w rms which is bridged for the sub with a single live feed and seperate rca's
Title: Re: Connecting sub to amp...
Post by: S11EPS on 05 April 2008, 23:05
The only problem i can see is unless you can seperate the signals the sub will get high notes like the fronts... i would get a small 2 way amp for the fronts and another for the sub.. mine uses a 2x50w rms for the fronts and a 1x400w rms which is bridged for the sub with a single live feed and seperate rca's

Most 4 channel amplifiers have filters in them, as running them in tri-mode (i.e. powering a pair of components using two channels and bridging another pair for the sub) is quite common.
As such, it's likely the amplifier will have an adjustable low pass filter for the two bridgeable channels that power the sub.
If not, then he'll need to run and inductor, which will do the same job and allow him to use the equipment he has.
Title: Re: Connecting sub to amp...
Post by: Shady Pioneer on 06 April 2008, 11:13
Thanks for the help guys.

I was thinking of this amp:

http://www.caraudiocentre.co.uk/product_m-jbl-gto-75-4_p-21965.htm

and this sub:

http://www.caraudiocentre.co.uk/product_m-kenwood-kfc-w3011-bx12p_p-23111.htm

Opinions? I've got about £160 for both.
Title: Re: Connecting sub to amp...
Post by: dan23 on 06 April 2008, 12:48
yeah they aint bad amps the JBL's, but there are sub and amp deals for around £150, just hunt around
Title: Re: Connecting sub to amp...
Post by: Shady Pioneer on 06 April 2008, 13:21
Yeah it's just all sub and amp deals I've seen around that price are only 2 channel amps  :sad:

However I've come up with a plan, I recently bought a pair of Juice (in phase) component speakers, sounded like a good deal but when it came to installing them, a tweeter blown and they are crap (I know they aren't amped yet but they should sound better than what they are).

So basically the place I bought them from I'm gonna moan at tomorrow, until they allow me to swap them round for a pair of Infinity Kappa components which should be far loads better, then buy an Infinity 4 channel amp I've seen for £99.99 and the Infinity sub which is £59.99.

Thought I may as well shell out a little more money seeing as I know from experience Infinity are really good especially for the money.
Title: Re: Connecting sub to amp...
Post by: dan23 on 06 April 2008, 13:25
yeah infinity are a good brand, so is fusion (value for money) and also JBL are good value for money
Title: Re: Connecting sub to amp...
Post by: Shady Pioneer on 06 April 2008, 15:03
Am I also correct in thinking that only the remote cable needs to be connected to the head unit then?

So the front speakers I connect this amp to just need to be connected to the amp?
Title: Re: Connecting sub to amp...
Post by: dan23 on 06 April 2008, 15:24
right if your running your front speakers via the amp then all you do is run wires from the speakers directly to the amp.

the reason for the remote is so it turns on and off via your stereo, so everytime the stereo is off the amp is off.

if you follow the diagram i made you make you will have no problmes wiring it all up
Title: Re: Connecting sub to amp...
Post by: Shady Pioneer on 06 April 2008, 15:27
Yeah I had a look at that, thanks for doing that  :smiley:

That's cool then, all I need to do now is buy all this stuff and get it all fitted, the hardest bit will be wiring the power cable to the front, I just don't know where I can get the cable through to, how do other Mk3 users get around this?
Title: Re: Connecting sub to amp...
Post by: boneybradley on 06 April 2008, 15:30
Yeah I had a look at that, thanks for doing that  :smiley:

That's cool then, all I need to do now is buy all this stuff and get it all fitted, the hardest bit will be wiring the power cable to the front, I just don't know where I can get the cable through to, how do other Mk3 users get around this?

behind the glovebox is a grommet thats routes the alarm wires inside the car (look mid way up left hand side of engine bay)
Title: Re: Connecting sub to amp...
Post by: Shady Pioneer on 06 April 2008, 15:38
Yeah I had a look at that, thanks for doing that  :smiley:

That's cool then, all I need to do now is buy all this stuff and get it all fitted, the hardest bit will be wiring the power cable to the front, I just don't know where I can get the cable through to, how do other Mk3 users get around this?

behind the glovebox is a grommet thats routes the alarm wires inside the car (look mid way up left hand side of engine bay)

Good man  :grin: thanks for that, will have a look in a bit for that.

I assume that means I don't have to fill in any holes with anything or what not, it'll be simply thread the power cable throught the same hole as these other wires?
Title: Re: Connecting sub to amp...
Post by: boneybradley on 06 April 2008, 15:46
I cut/modified the original grommit and reused this...but you need to remove the glovebox to thread the wire through
Title: Re: Connecting sub to amp...
Post by: Shady Pioneer on 06 April 2008, 15:54
Oh really? Damn...I kind know what I'm doing but I don't wanna end up screwing my car up by doing this lol!...
Title: Re: Connecting sub to amp...
Post by: boneybradley on 06 April 2008, 15:56
lower glovebox has 6 bolts and the upper about 8... should be simple to do?
Title: Re: Connecting sub to amp...
Post by: Shady Pioneer on 06 April 2008, 15:59
Oh hold, in your last post did you mean glovebox? LOL! You said gearbox  :drool:
Title: Re: Connecting sub to amp...
Post by: dan23 on 06 April 2008, 16:51
Oh hold, in your last post did you mean glovebox? LOL! You said gearbox  :drool:

lol :laugh: :shocked: :tongue:
Title: Re: Connecting sub to amp...
Post by: Shady Pioneer on 06 April 2008, 17:07
Oh hold, in your last post did you mean glovebox? LOL! You said gearbox  :drool:

lol :laugh: :shocked: :tongue:

Oh yeah, go and change it now to make me look a fool LOL! Thanks for the help though man, will keep people updated on the audio system  :grin:
Title: Re: Connecting sub to amp...
Post by: boneybradley on 06 April 2008, 17:09
Oh hold, in your last post did you mean glovebox? LOL! You said gearbox  :drool:

lol :laugh: :shocked: :tongue:

Oh yeah, go and change it now to make me look a fool LOL! Thanks for the help though man, will keep people updated on the audio system  :grin:

 :lipsrsealed: :lipsrsealed: :lipsrsealed: :wink: :wink: :wink: :grin: :grin: :grin: