Hey i have an 09 tc with the stock head unit, and i want to run an amp for component speakers i bought, can i connect the amp directly to the back of the radio or do you need an adapter or something...? thankzz

 

I think you will need a hi/low converter, they do not run much. You can find the wires you need behind the radio on this site or @ the12volt.com

 

I'm fairly sure the '09 HU has RCA outputs, so yes, you can connect an amp "directly" using RCA cables. Earlier models such as '05 & '06 didn't have RCA outputs, so an LOC was required if the amp being added didn't have speaker-level inputs.

 

I have an 08 and want to connect an amp with sub to factory radio, mine has it as the model is the pioneer model with scion branding, does anyone know how many volts the rca factory pre outs are to help in selection of an amp?

 

^ I can't recall for certain, but seem to remember them being 2 volts. If you want to try a search it's probably been posted here, but may have been a couple years ago, so it could be hard to find.

When it comes to matching with an amp, if you really want it to be optimal you'll need more than just the max or RMS output, as the 2.0v or whatever is specified may not be listed with a tolerance, such that it might produce objectionable distortion at that level, and the HU output to amp input impedance is another aspect to consider. The best way to be sure would be to monitor the HU's outputs on an oscilloscope while measuring it's output voltage, so you could see how much voltage it puts out before producing distortion.