mono Amp

There sure is.  Many people use mono amps with 2 speakers.  Play around with the options in this wiring guide:

http://www.sounddomain.com/shop/wooferwizard.pl

Just remember most mono amps aren't stable when run under a 1 ohm load. 

Is that the same setup  i can use for normal speakers not subs?

markcars to answer your question a stereo amp does have two channels and in some instances some have separate power supplies for each channel.

If I am assuming right, stevdart was trying to say that mono amps are basically designed for sub applications since they are normally class D amps and designed for raw power and not clarity.  Since subs can handle a little more distortion than mid-high freq speakers mono amp are normally required to power them.  When it comes to mid-highs 2-4 channel amps are reccommended since they play higher frequencies with less distortion.

Using mono amps for main channels (two for stereo, as you suggest) allows you to achieve much higher sound quality than using stereo amps.  Some of the absolute best stereo amps actually do use two seperate mono amps in one chassis.  As long as you have chosen the amps properly (class A or A/B, not class D or X) you can certainly achieve better sound using seperate mono amps.  The setup is far more difficult, however.  Beyond the obvious space, cost and wiring differences, the input sensitivity and output gain (if they have this) must be matched as closely as possible, which requires using the proper equipment.  A dedicated stereo amp (which usually shares certain power supply and input components, and sometimes shares output components as well) uses a unity gain for both channels.  Oh, and in addition to the advantages in SQ, channel seperation, s/n ratio, etc. that can be achieved with the right mono amps, you can also more easily use certain equipment to adjust them (both time alignment and relative output levels) to compensate for speaker placement to get the proper sound stage in your driver's seat.

If you can afford it and have the equipment and expertise to set them up properly, seperate amps for each sound channel can be the best way to go for ultimate SQ.