HD150 Tone Controls

I recently bought an HD150, and it seems that if the tone controls (specifically bass) are at zero, there is hardly any output. Is this normal? If I have all the tones at zero, and the gain and master almost to ten, there is hardly any output. Once I turn the tone controls up, everything seems fine.

I am sorry I never saw this post. That IS normal. I don't personally have a 150 but a friend does. Just called him and his is the same way. Mike.

Thanks Mike.