Guitar to line in

[served]

Hi.

I would like to connect my guitar rig to Line In. What do I need for this?
I assumed that I would need a DI Box, but no XLR is actually needed.  
There is a impedance mismatch I know, but how can I remove that?
My main issue with this topic is that I am afraid that it would not sound the same.
Ofcorse I will be using some efects and simulators. But they dont have and Line Out. I need to create one.

Any ideas?

[ayayay!]

Do a search for a cab sim.  Sounds like that's what you need. 

[served]

yes Cab sim is what I am also after. But I thought that Cabsim output is not suitable.

[Fender3D]

"line level" is a vague amount of signal...
if you're feeding your PC audio card, -10dBV should be enough,
if you're feeding a power amp then you should have 0dBV or +4dBV depending on equipment.
Usually 47k impedance works.
You must trim your cab sim output to obtain your needings.

[therecordingart]

You may only need a buffer depending on the output level of your guitar. That will take care of the impedance issue. If you're going to build an opamp buffer you might as well just make the gain variable between a gain of 10 and unity.  The question is do you want a balanced output?

+4dbu is 1.23v RMS while -10dbv is about .317v RMS.

This is a really good read:

http://www.jensen-transformers.com/an/an003.pdf

Section 2.4 give an easy solution for balancing the output. It does say the TL07x and TL08x aren't adequate for the method in this section, but I'm not sure which chips are. Maybe PRR or RG or the other usual suspects can chime in?