There are many forms of audio(as in powering speakers)...
Amplifier, integrated amplifier and receiver.
Amplifier is just that, it amps an incoming signal.
Integrated amplifier has an on-board volume control("amps" don't have volume control)
Receiver is amplifier, on-board volume control and a tuner(am/fm).
Some amps have volume attenuation, which "technically" makes them integrated amps...
What keeps a "volume attenuating amp" from being just called an integrated amp is the ONE input it has(not several like an integrated has)
(does not have ANY form of volume attenuation)
Amplifier with on-board volume attenuation...http://www.amazon.com/Pyle-2x75W-Ste...0020332&sr=1-1
(has volume, bass/treble...but only ONE input)
(the only thing separating this from a receiver is the "lack" of a tuner-am/fm)
When you buy an amplifier(regardless if it does or doesn't have volume attenuation)...you buy what is known as a pre-amplifer(pre-amp)...also known as a control amp.http://www.amazon.com/Parasound-Clas...020804&sr=1-33
So, in your case...if your TV has an analog output, and it can be set variable...then the TV itself will act as the pre-amp. If the analog output of your TV is NOT capable of being set variable...then you need something to control the amp between the TV and AMP(or you just buy an amp with a volume attenuator, integrated amp or receiver)