NAP 250 runs hot

Posted by: Jens on 27 November 2000

Hi All,

I have recently upgraded my NAP 110 to a NAP 250, and while there have been a heap of positive differences (the sound is much, much larger, dynamics are much more exciting etc), I have also noticed that the new amp runs warmer than the old one. I realize that the surface area: volume ratio of the NAP250 is not as high as that of the NAP110, and I also think that I tend to play the new amp louder than its predecessor, hence the increase in temperature. However, on a couple of occasions when playing CDs fairly loudly (7 o'clock on the old NAC82, where zero gain is at approx. 4 o'clock) for 30-40 minutes, I have activated the thermal trip, and the music has stopped. It's always disappointing to be stopped dead in mid-flow, and I am wondering how many of you have had similar experiences. Needless to say this never happened in the days of the NAP 110 (but I don't think that those amps had a thermal trip built in).

The rest of the system is as follows:
CDX, LP12 (I haven't managed to trip it playing records yet), Hicap, NAC A5, Epos 22.

Posted on: 27 November 2000 by Ron Toolsie

In the days when I had 'only' a single 250, I found that I too would occasionally send it into thermal protection. There are a couple ways around this. One is to get a fan and direct its blast onto the NAP250 chassis-sort of like a DIY 135! The other way (and the way I did it) was to place the 250 on a shelf after removing the shelf board and replacing it instead with 2 lead bars. This way the undersurface of the 250 can radiate heat unimpeded by a solid and usually black object (aka shelf) that sits only millimetres away from the undersurface.
I take it that you do not have your CDX stacked ontop of your 250....

Ron
Dum spiro audio
Dum audio vivo

http://homepages.go.com/~rontoolsie/index1.html

Posted on: 27 November 2000 by Martin Payne

Jens,

several people here have found that non-Naim cables can make the amps run hot (and maybe die later, too).

Are you using Naim cables?

cheers, Martin