Hey i just got a new tibby, and i want to get sum subs, but i dont want to replace me head unit. Can i use the stock 1 , and hook up a amp to it?? thanks fred

 

I know for a fact that you can't hook up a amp directly to the head unit but I've heard that you can use some type of connector to do it though, but I'm not sure what that is, sorry.

 

there is an adapter that you can get at Circuit City that connects to your speaker outputs on the back of the head unit that changes the signal so you can hook up RCA's to it to run it back to the amp it'll run ya about $20.

 

The adapter is called a line level converter. It takes your speaker wire in on one side and converts them out to an rca terminal on the other. Most amps have high level (speaker wire) inputs already on the amp so you don't have to buy the converter so if you didn't buy the amp yet look for this when you buy one. And I work at Jerkit Silly and we don't sell them for $20 there more around the $40 not to sure of excact price because I instruct most of my customer to do what I've suggested to you it saves you money in the long run if you ever get a new head unit, you won't have $40 lying around doing nothing rolleyes.gif . Hope all this helps let me know I will be more than happy to help you if you need it.

 

I have 2 amps running off my stock head unit. It is a piece of cake.

Just make sure your amp has speaker level inputs. It's that easy.

If your amp does not have them, then you will need the line level converters that Jaws99 was talking about.

 

thx guys, i did get a line level converter and it was only 25 buck from my buddy at custom connections, "its a shop by me" anyways i got a sony explod 710 amp and 2 jl 10's and its bumppin . hehe thx fred

 

Yes, one way to go is the line out converter...or the line level converter or whatever you called it. You could also just make your own RCA ends by soldering the lines from your head unit, but you'll want to make sure that your amp has a crossover to cut out the high and mid frequencies..

I did the same thing (line out converter) in my Tibby, except I bought nice subs..

2 12" Crossfire P112D @ 2 ohms
Crossfire TEK400.1 monoblock

 

Hey clarion used to make a pice that was a fm modulator that also had Rca out puts on it to run a amp. I have to warn you though when you convert high level (ie radio out puts) to rca voltage (pre out out puts) you do have a tendacy to lose low signal freq and high singal freqs. What I recomond is buying a amp that offers high level inputs with the option of low level out puts on the same amp. Autotek used to offer that on there street machine series. That way you can dasiy chain more than one amp after it is converted.

 

Well, if you're a hardware hack like me, you could always trace the pre-amp signal path from the stock head unit, and use that as a line out. The trick is to get the signal path after the volume control, so that the volume control still works like you want/expect.

What you'll be looking for is an op-amp (Probably a TL072 IC chip) that's connected to the volume control knob. There will be 8 pins on the chip. 2 go to power, 2 go to the amplifier circuits, (those are the ones that you need to tap into) 2 will go to the left and right pre-amp source, and 2 will go through the volume control back to the output for feedback gain control.

Tapping into this circuit will get you somewhere between 500 mV and 3V pre-outs, depending on the rail voltage in your deck.

You may need to add an additional op-amp to the circuit, depending on the input impedance of the internal amplifier, but I've only seen one deck where this was needed.

Using this as a source will (naturally) void your warantee on your deck, but will give you the cleanest possible signal outputs that you can get from a factory deck. In fact, if you do this correctly, your factory deck will be just as good or better than most of the aftermarket stuff out there. I've modified several factory decks in this fashion for people who want to compete in sound competitions with a very stealth factory looking installation.

Oh, and many factory CD decks can be made much cleaner by substituting the cheap op amps that they use with better ones. There will be 4-5 dual op-amp chips on the pre-amp phase of a typical head unit. If you do this, and (possibly) add the extra op-amps to get a 4-6V line out, you will be running with the top 2% of all the aftermarket decks out there. The only things that you're likely to be missing would be DSP/EQ functions of the high end decks (Which I never use anyway. All that stuff goes to outboard equipment.)

So, there's the cheap way (Amp with speaker level inputs.)
Advantage: It's cheap. It works.
Disadvantage: Lose a pair of speakers, or suffer from distortion problems.

Next up, line lever converters
Advantage: still fairly cheap, keep all speakers (You can hook up converters in parallel without affecting load impedance from the deck much.)
Disadvantage: Lower quality output, prone to distortion and interference. Better units are more acceptable, but you are still limited in quality with this solution. You're also left with useless hardware if you ever upgrade. tongue.gif

And finally adding your own line level outputs:
Advantage: Cleanest possible sound (From that source), still costs less than decent aftermarket deck, no dependance on internal deck amplifier if you don't want it. Very upgradable. smile.gif
Disadvantage: Requires decent electronic knowledge, voids factory warantee, cannot restore car to factory condition. Also, if you screw up, youve got no deck at all. rolleyes.gif

Anyway, since you have your option picked out I guess this is just a FYI.