Understanding Mcintosh Meters?


This is probably a stupid question, or atleast one I should be able to answer myself, being that I did graduate with a degree in computer engineering, but I recently got a mcintosh ma6450, and was wondering how I make sense of the meters. I understand what they measure, and what it means, but how do i know when I am close to clipping.

Let me explain further. the amp is rated 100wpc, in to 4 ohms and the meters read from .01 to 100 watts with the final mark being 200 watts. But what if my speakers are 8ohms? I know that means my amp produces about 50 watts in to 8ohms, but does that mean that I can only take the meters about 1/2 way before I will clip, or do I go by the decibels, meaning 0db is really the max before clipping, only instead of producing 100wpc (0db corresponds to 100w watts on the meters), the amp is only producing ~50wpc since the speakers are 8ohms.

Hope I explained my question well enough. Thanks for your help.

farjamed
As to the last post - I am not familiar with the model amp you mentioned, my explanation was based on current amps sold by the company - you may want to look at the manual, or call the company, to find out if the clipping protection I described is in your model.
Hi farjamed, I had posted a question on power level DB meters a while back, do a search for "Amplifer DB meters".

Turns out that they are essentially useless and have little real world meaning. They are a nice marketing tool. I just taped over the meters to prevent them distracting me. Unless you think they look cool just ignore them.

Bob
"Blue Meter" with glass front, nice looking, but totally worthless!! Don't worry about the meters they will never tell a story on your speaker or systems capability, if it sounds good go with it, you will know just like everybody else having amps with NO meters when there is an issue of being overdriven. I owned several mcintosh pieces over the years, basically you can buy white ipod or you can buy a fancy "Skined" Ipod to make it look better, thats all the meters do for you, they give you a unique look.
Totally worthless? Don't know about that. Does a car need a tachometer? No, but I like knowing what's going on engine wise. Same with audio. They will let you know when you're about to "redline" the amp (not the speakers though).

To the OP: Don't know the 6450 that well, but I think it's new enough that it should have a "power guard" or "power sentry" monioring circuit that would take the guess work out of meter calculations.

Above all else, your ears are the best meters. Turn up the volume slowly until you begin to hear stress out of the speakers, note where the meters are and keep it under that level. It doesn't take long to burn out a tweeter or part of a crossover it you go into clipping too long.