Do I need a pre amp?

[GuitarFogie]

I have a "Sonic Impact Boom Bag" (basically a back pack with an amplified speaker system built in). It is intended to take an output signal from an Ipod, Walkman(yes I said a Walkman), or other personal sound system. I am thinking that it would be a great practice amp for an electric guitar. As the intended input is coming from an existing preamp, will I need to incorporate a preamp between my guitar and the input of the amplifier. Unfortunately the specs of the unit is no longer available so I do not know what the input specs should be. Anyone have any ideas?

 

[Guerilla]

Yes You need to buy or build somthing like this : Tech 21 SansAmp Character Blonde V2 – Thomann Danmark
Its simulates what a guitaramp and guitarspeaker does to make it sound right. Furthermore it can output a linelevel signal as opposed to your guitar that only outputs a weak "mic" signal. You can buy cheaper but this i linked should be good

 

[MAAC0]

The problem is guitar pick-ups are usually very high impedance 100K or more and when You connect them to a normal amp 10-20K impedance You get that thin sound. Yes You need some sort of impedance matching gig. An injection box or guitar pedal is usually used.

 

[thoglette]

Impedance problems are just the start of it.
Guitar amps are both non-linear, clip "funny" and have weird frequency responses.

Shortest answer: get a Vox amPlug
Short answer: build something from RunOffGroove.com (like a Ginger + Condor combo)
Long Answer:read these threads
Battery Powered Princeton
Move over Fender and Marshall

 

[GuitarFogie]

Thanks for the info people. I see that I need to think this through