Thanks for your reply.

The bass is good. I am able watch the movies without the sub and able to feel the explosiions and the gun shots and the car chases.

What I meant it is below 40Hz the response is -10db. By adding a sub and crossing over at 60Hz I should get better bass than what I am getting now. That is not at all a worry for me as of now.

Comming down to Amp getting hot. Hot is a relative term. I would try to measure it in this way. I am able to keep my palm on the amp for about 10 secs. Then I feel like removing it. Does it mean it is hot, warm etc. It is hard to tell when do we say it is hot or warm is a relative term.

Another thing I observed is whether I run it for half hour or 3 hours, I feel the amp is at the same degree of hotness. In that context I feel comfortable.

Also another question is should I leave the amp in the running mode or should I switch it off when the preamp is not running.