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 Former member
G'day Jens,
The 250 is quite a warm running amp by nature. The harder you drive it, the warmer it gets. Unfortunately, there is a limit to how hard it can be driven and you might have reached its limits.
I fully understand how a more powerful and articulate amp might compel one to play more loudly. However, if you find that you are regularly tripping the thermal switch and your dealer can confirm there is nothing wrong with the unit, you might just have to find yourself a pair of fan-cooled 135s. I have done just that, and I find myself tripping their cooling fans on a regular basis, but at least the music keeps pumping. Enjoy the music.
Jame
[This message was edited by James Jong on MONDAY 27 November 2000 at 20:34.]
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
