how can i identify a jl sub

Pstroke96 · Sep 5, 2011

if it is wired for duals what does that mean to me? im not really following you

Irishcream · Sep 5, 2011

at single voice coil it will be running at 4 ohms , with duals it will be running at 2 ohms, twice the power from the same amp and sub. Just gotta make sure you get an amp that is stable down from 4 ohms. I've ran a Rockford Fosgate all the way down to 0 ohms. Ran two dual voice coil subs on one amp.

06powerstroke · Sep 5, 2011

Irishcream said:
:whs:
It will have two sets of spade connectors or screw terminals. Make sure the gain is all the way up in the amp and control the level from the Head unit. By turning the gain down and trying to turn the volume up you are sending a weak signal to the sub. Strong signal from the amp is very important.

You do not want the gain all the way up. The gain needs to match the voltage that your HU puts out.

Pstroke96 · Sep 5, 2011

Irishcream said:
at single voice coil it will be running at 4 ohms , with duals it will be running at 2 ohms, twice the power from the same amp and sub. Just gotta make sure you get an amp that is stable down from 4 ohms. I've ran a Rockford Fosgate all the way down to 0 ohms. Ran two dual voice coil subs on one amp.

okay that makes sense so if it has two hookups do i hook one to each output on the amp or since i have it bridged just put them together?

06powerstroke said:
You do not want the gain all the way up. The gain needs to match the voltage that your HU puts out.

not to sound like a tard, but how do i do that?

Pstroke96 · Sep 5, 2011

heres the hookup exactly how it was when i opened it sorry for the crappy cell pic

06powerstroke · Sep 5, 2011

Pstroke96 said:
not to sound like a tard, but how do i do that?

Your HU should state what it's output voltage is. The amp's manual should tell you the voltage range for the gain. The sub looks like a single voice coil.

Pstroke96 · Sep 5, 2011

06powerstroke said:
Your HU should state what it's output voltage is. The amp's manual should tell you the voltage range for the gain. The sub looks like a single voice coil.

damn then why are there two places for connections on each side?

also i bought the whole setup from a friend i didnt get any paperwork with it

Irishcream · Sep 5, 2011

I have been a sound technician for 10 years with a very large music company so I do know my stuff but maybe you know something that I don't know. Most amps are not within arms reach of the driver therefore turning up the gain at the same rate as the head unit may become very difficult.
By turning the gain down on the amp you are limiting the signal strength sent to the speaker so you will cause distortion in the signal. You will then run the risk of damaging your speaker.
By controlling the sub/amp using the head unit output you eliminate any distortion because the signal is being sent through RCA cables and does not degrade it merely limits the volume of the signal. Now if you were running a high output signal to the amp then you will get more distortion by running it through the head unit.
When you hook up the sub using both connections plug the +to+ and -to- if that makes sense then run one side to the box terminal.

06powerstroke · Sep 5, 2011

Pstroke96 said:
damn then why are there two places for connections on each side?

also i bought the whole setup from a friend i didnt get any paperwork with it

There are spots for two connections but notice they are both attached to the same connection...

Irishcream · Sep 5, 2011

I thought it was also hooked to the other side? Looks like double wires on each terminal. Get rid of the dental floss wires and get some real cables. Just my opinion.

06powerstroke · Sep 5, 2011

Irishcream said:
I have been a sound technician for 10 years with a very large music company so I do know my stuff but maybe you know something that I don't know. Most amps are not within arms reach of the driver therefore turning up the gain at the same rate as the head unit may become very difficult.
By turning the gain down on the amp you are limiting the signal strength sent to the speaker so you will cause distortion in the signal. You will then run the risk of damaging your speaker.
By controlling the sub/amp using the head unit output you eliminate any distortion because the signal is being sent through RCA cables and does not degrade it merely limits the volume of the signal. Now if you were running a high output signal to the amp then you will get more distortion by running it through the head unit.
When you hook up the sub using both connections plug the +to+ and -to- if that makes sense then run one side to the box terminal.

Turning the gain down will not damage the speaker, it adjusts the sensitivity of the amp to match the rate the volume changing at your door speakers. If his HU has a very low pre-out voltage he may be able to get away with having it all the way up. However if the pre-outs put out decent power than the amp will turn up very fast, much faster than the rest of the system. That's why it needs to match your setup, best way I have found to tune it is simply by ear...

On the flip side having the gain all the way up will not damage the speaker like others think, as long as you keep your HU volume lower. Gain will simply determine when the amp hits it's peak.

06powerstroke · Sep 5, 2011

Irishcream said:
I thought it was also hooked to the other side? Looks like double wires on each terminal. Get rid of the dental floss wires and get some real cables. Just my opinion.

IIRC JL never made a double VC W0.

Irishcream · Sep 5, 2011

I agree with you on the gain not damaging the sub. Most HU's have a sub out level control so that's how I meant to control it, not just by turning the bass down on the EQ. A few of the better amps now come with a gain remote control so if you really wanted to control it you could. I have an amp I bought about 3 years ago still sitting in the box on a shelf in my basement that has a control. I think it's a kenwood D-class 1100 watt mono block.

06powerstroke · Sep 5, 2011

Irishcream said:
I agree with you on the gain not damaging the sub. Most HU's have a sub out level control so that's how I meant to control it, not just by turning the bass down on the EQ. A few of the better amps now come with a gain remote control so if you really wanted to control it you could. I have an amp I bought about 3 years ago still sitting in the box on a shelf in my basement that has a control. I think it's a kenwood D-class 1100 watt mono block.

That actually would work just fine, having the gain all the way up and turning the sub output down. Then if a song has low bass you could turn it up a bit. However all your doing is turning your amp sensitivity all the way up then you are reducing your hu's output sensitivity, which seems like a strange way to do it. I like to keep the sub output at 0 and tune the amp to match, then if a song has low bass put it to +1 or +2. There are many ways to achieve the same thing.

Irishcream · Sep 5, 2011

The only thing I usually like to control is the Hz or hurts whatever way it's spelled because not all music needs booming bass, I like country music so you'll never hear me coming from a block away but I'd still like it to kick like a mule.

UNBROKEN · Sep 10, 2011

Irishcream said:
Make sure the gain is all the way up in the amp and control the level from the Head unit. By turning the gain down and trying to turn the volume up you are sending a weak signal to the sub. Strong signal from the amp is very important.

You should never give audio advice again. That statement right there proves you have no idea what you're talking about.

UNBROKEN · Sep 10, 2011

Irishcream said:
I have been a sound technician for 10 years with a very large music company so I do know my stuff but maybe you know something that I don't know. Most amps are not within arms reach of the driver therefore turning up the gain at the same rate as the head unit may become very difficult.
By turning the gain down on the amp you are limiting the signal strength sent to the speaker so you will cause distortion in the signal. You will then run the risk of damaging your speaker.
By controlling the sub/amp using the head unit output you eliminate any distortion because the signal is being sent through RCA cables and does not degrade it merely limits the volume of the signal. Now if you were running a high output signal to the amp then you will get more distortion by running it through the head unit.
When you hook up the sub using both connections plug the +to+ and -to- if that makes sense then run one side to the box terminal.

Seriously...quit now. You may have been some sort of sound technician but you have sero understanding of level matching a car audio system.
By turning the gain all the way up you will cause clipping and speaker damage.

The gain is not a phucking volume knob and it has nothing to do with the sub control on the head unit. It's there to level match to the head unit's output signal and nothing more.

OP...please don't listen to this guy, he's steering you down a path to equipment damage.

Irishcream · Sep 11, 2011

UNBROKEN said:
Seriously...quit now. You may have been some sort of sound technician but you have sero understanding of level matching a car audio system.
By turning the gain all the way up you will cause clipping and speaker damage

You cannot cause an amp to "clip" when there is no signal. You control the volume of the signal through the sub output on the head unit. By having the gain all the way up does not mean you are sending any power to the speaker. The "amplifier" amplifies the signal it gets from the head unit. What you are saying is that the speakers are at full blast no matter what the volume you turn it to on the head unit. That is incorrect. try turning up your head unit with the gain on the sub amp at a low level and the speakers will blow because you are sending a distorted signal.

UNBROKEN · Sep 11, 2011

Once you run the head unit up past a certain point dependent on each head unit you WILL send a clipped signal...that's a fact. That point is much lower with the amp gainall the way up.
Gains should be set with a DMM or o-scope and unclipped test tones starting with the amp gain all the way down and the head unit volume at roughly 3/4 to leave some room for error when cranking it up.

ALL head units clip at some point...even my competition head unit and it's among the best of the best with a supposedly unclipped 8 volt pre-out.