sub wiring question

robkendall · Post by **robkendall** » Thu Jun 29, 2006 9:18 am

ive got a bloody great big speaker in a box from an old guitar amp and was wondering if i could just wire this into the cars stereo system.....if so how?
not bothered about running it through and amp for now....just wanted something a bit extra, or is it not worth it?
basically the head unit is a sony with 10disc changer....it has the rca outputs on it, but the 'sub' only has a big jack plug type plug on the wires.....how does one do it?

rgrds
rob

Bakke · Post by **Bakke** » Thu Jun 29, 2006 9:44 am

Your headunit doesn't have enough power power to run the sub, you risque to see your headunit going up in smoke ...

robkendall · Post by **robkendall** » Thu Jun 29, 2006 9:54 am

ah...so definitely though an amp regardless?
rgrds
rob

piper1st · Post by **piper1st** » Thu Jun 29, 2006 9:56 am

very true bakke ... You will defoe need an amp!! especially since car speakers are 4ohms and house/pro speakers are generally 8ohms, so thats something to check!

Has the guitar speaker's box got a big hole in the back?

robkendall · Post by **robkendall** » Thu Jun 29, 2006 9:59 am

no hole in the back, no......
its just literally a big box with the speaker in the centre front.
to run the guitar through it you had to sit a seperate amp onto and plug it in, then the guitar into that....so its a box with a speaker and a big wire with a big jack plug on it.

rgrds
rob

Bakke · Post by **Bakke** » Thu Jun 29, 2006 10:05 am

The 4/8 ohms doesn't matter on an amp, it won't just go as loud as a normal sub. My subs are even wired to 1.5 ohms

piper1st · Post by **piper1st** » Thu Jun 29, 2006 10:15 am

you'd proper struggle with an 8ohms speaker and no amp though!

(thats what i ment)

As for wiring ... there are two types of jack connectors ...

Stereo (ring/tip/sleave)
mono (tip/sleave)

1. Sleeve: usually ground
2. Ring: Right-hand channel for stereo signals, negative phase for balanced mono signals, power supply for power-requiring mono signal sources
3. Tip: Left-hand channel for stereo signals, positive phase for balanced mono signals, signal line for unbalanced mono signals
4. Insulating rings

(from Wikipedia)

robkendall · Post by **robkendall** » Thu Jun 29, 2006 12:03 pm

the bottom jack plug.

just had the box apart - theres no markings on the speaker at all.....nothing.
theres only two wires, blue and brown.

any ideas?

basically all i want to know is how do i wire this up as a speaker that can do bass from both left and right channels, or cant i?

sorry if this sounds dense to those who know, but i dont, so im asking!!???
rgrds
rob

Bakke · Post by **Bakke** » Thu Jun 29, 2006 12:18 pm

There is no need for left/right since subs only play mono ...

The easiest way is to connect them is to take the unused wires from the rear speakers (if they aren't used)

And don't forget to put a filter between it so your sub isn't playing all the tones, but only the lower frequencies ...

Greetz
Bakke

Bakke · Post by **Bakke** » Thu Jun 29, 2006 12:23 pm

but again ... your HU maybe produces 40W peak/ 10W Rms I think with that power you won't hear the sub playing.

I've got 2 amps delvering 1000W peak/300W rms to feed my subs and even than it isn't what it should be in my ears ...

robkendall · Post by **robkendall** » Thu Jun 29, 2006 12:40 pm

thanks for all your help guys.....

i will wire it in for now and see what it does....it isnt a true sub as such, so i may get away with something?
ive got a 1000w amp and cap kit coming (cheap off a scrap pug!), so will wire that lot in at a later date....

thanks again!

rgrds
rob

480_rocket · Post by **480_rocket** » Fri Jun 30, 2006 10:24 am

Wattage isn't everything, sensitivity plays an important part! A guitar speaker will do little as a sub, unless it was for bass guitar! From a head unit, into a 8ohm driver you'll get about 10w

robkendall · Post by **robkendall** » Fri Jun 30, 2006 1:27 pm

yeah....sorry, it is a bass speaker or a speaker for a bass guitar should i say.
i'll have a fiddle anyways....if theres not much difference with it, ive lost nowt, as it was free along with about a dozen others!

now if it does make a difference, i will wire the lot up in a full boot install....10X15inch subs would make my missus happy (cough!)

rgrds
rob