"MOSFET" wrote in message
m...
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MOSFET... i wanted to ask you....
i just noticed your amp ratings for your Midbass....
JL VR series( i read from their site) is capable of 60W RMS and your
driving these with almost the double the power.... (112W RMS).... so is
other speakers... (Kenwood X168 6.5" capable of 50W RMS and driving
them at 90W RMS)
wouldnt this fry your speakers??

Just to elaborate a little more on your question...

I frankly would be perfectly comfortable using a 200 watt RMS amp for my
JL's or my Kenwoods. I remember (like it was yesterday) 16 years ago when
I was buying my first system and asked the salesman that very same
question. I'll never forget what he said: "don't worry, your speakers will
cry for help before they are damaged". In other words, your speakers will
begin to distort BEFORE they reach their breaking point. I am careful NOT
to let my speakers distort because as you correctly pointed out, I COULD
destroy those speakers with the amps that I have connected to them. Of
course, this is not difficult as distortion sounds TERRIBLE and if I hear
it I QUICKLY turn something down.



That's kinda right and kinda wrong. If you have your system set up with
proper filtering it is still very possible to reach the thermal limits of
the drivers before distortion occurs, in fact at this point the distortion
will be the beginning of the end as the glue on the former heats up, the
coil expands and the driver begins to rub. Mechanical distortion or cone
breakup does not always occur as the VC of the driver reaches the
temperature of the surface of the sun (joking on the temp thing).

Another thing to consider is that mechanical limits cannot always be heard.
Before the Alpine and steep slopes I could have easily chewed up one of my
seas drivers because I said, "hmmmm that kick drum did not sound that clicky
when I RECORDED IT" If I had not recorded it and knew the sound of the kick
I would not have known I was bottoming out the driver. A little adjustment
in XO freq and the problem was solved but it could have been damaging if I
had just bought a new CD and was hammering it just thinking it was a clicky
kick (BTW Seas CA18RNX drivers sound just like batter "click" when they
bottom out )

As of now I am crossing at 63Hz at 24dB an octave and have no problems. The
Seas have hella excursion for a mid/bass.

Another thing to consider is that today's popular music has absolutely NO
dynamic range, meaning that the average power level going to the drive is
much higher than it was when music actually had dynamics. This further
compounds the problem of :

A: not hearing distortion due to the cacophony of sound barraging your
cerebellum and

B: Not having distortion and having higher average power levels overheating
the coil.

This is why in pro rigs there are RMS limiters and peak limiters....

Chad