building a line driver

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I've spent a good portion of the day going through the site looking for a schematic that I found before regarding building your own line driver for my car. I'll admit upfront that my electronics experience, when it comes to building things, is extremely limited. I know how to solder, i know the primitive basics of parts used, but thats about it.

I found a post last week that ended up linking me to a really easy-to-follow plan for a line driver. The site had not just a schematic but also a picture of what the circuitry looked like when assembled and gave a list of parts needed--including radio shack and comparable part numbers. What I've found in my searches today though, has been limited to schematics only and while I can read some of them, for the most part, I'm not completely comfortable using them. I am confident in my ability to do the project though, I'm just looking for a simpler guide than the traditional schematic.

I'm wanting to juice up the low level RCA signal in my car from where it sits at 4v to a healthy 10v if not more. I dont want it indefinately strong, naturally but to have a better output would be nice. Also, something that will balance and keep the signal clean as much as possible.

I appreciate everyones time with this.
 
I just finished building this preamp for the home theater in my RV trailer. I needed a simple line level preamp that I could use to switch multiple inputs. It is a simple circuit from ESP that uses Jfet opamps and it sounds just fine.
 

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I'm not sure how much gain you need for your line driver. The preamp circuit is presently set for a gain of 10 or 20dB. I found this to be excessive. Most of the car audio accessories tend to have a pretty high output and really only need attentuation. My DVD player has an output of 2.5V and my CD/tuner has an output of 2V. This is more than what is needed to drive the amps to full output. If you have too much gain you may find the 100K volume controls overly sensitive. I reduced my gain down to 2 which was still more than adequate. I built mine on a pcb that I made. I added some extra filtering/decoupling caps which really turned out to be unnecessary because I found the noise levels from sources to be higher than the preamp circuitry, which is really quiet on its own.
 
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