I recently purchased the Puritan PSM156, and 1 thing I noticed is that my 500DR appears to be warmer to the touch than I ever remember. Is such a thing normal?
I recall that if I don’t use my amp, it is cold to the touch and never warm. But now my 500DR is warm all the time.
@Dan_M has one , with 500 dr.
I would remove the 156 and see if it cools down again. If it does, maybe give Puritan a call and see if they can explain it.
I had no heat issues with my 500 (non DR) and 156.
I’m using a stock Wireworld Two mains block and have just felt my 500DR and can confirm it’s pretty cool. There’s a lot of components in a 156 maybe it’s creating some sort of resistance that 500 doesn’t like? Probably worth switching to another block to see if it cools down?
Tks guys, I will email Mike as well as switch back to my Wireword for now.
Also it is the 500DR head unit that is warm (as in it has been playing music for hours, but it is not). The PSU is not that warm. Weird.
I do indeed have the Puritan 156 and the head unit is cold unless I play music loud. Something else going on here?
The head unit has all the output devices and the regulation circuits/devices. The PS box should never be more than slightly warm.
Is that the mains “purifier” thing? If so, I read somewhere that it could inject ultrasonic noise, which if it does potentially could be causing the amp to work even when no hifi input signal. I’ve no idea how likely, but I guess it would be a fault condition if if does happen.
Puritan’s Mike replied me and I pasted it here. I hoped he don’t mind but I think is quite a technical reply that forum members can discuss.
Hi,
The 500DR is biased for class AB operation , providing the sweet Class A sound for low level signals but switching to Class B brutal power for the loud peaks.
Operating for the first ? watts in class A, whilst not generating the heat levels of pure class A amplifiers, where the external heatsinks can be uncomfortable to touch, it does generate heat and cannot be compared in this respect to amplifiers biased for pure Class B operation which have a very low no music playing current draw . (But have a compromised sound)
I am not sure how many Watts the 500DR delivers in Class A before sliding towards Class B operation but I have seen some specification figures that quote 60W of consumption with no load (music). 60W of heating is about the same as two sets of hair curling tongs, and so yes you will detect warming even without music playing.
Very best wishes – Mike
As you can see I have no idea my 500DR is operating in class A initially?? Or what is bias meaning. I have only heard of bias while reading Linn Klimax Solo 500 marketing material 
That in no way explains why your 500 is hotter when plugged through the Puritan then when not! Try asking him that. I think it might be beneficial if you can try and measure the temperatures with and without the Puritan. Or equally useful would be measuring the current quiescent (on but idle) current drawn with and without Puritan (you can use one of those plug-in meters designed for monitoring electricity consumption within the home) packet.
Yes I just woke up and now plugged in my Wirewowrld to run for the day and see how it feel when not listening to music. Unfortunately no measuring device. Maybe I can go invest some iPhone temperature accessories 
No clinical thermometeror meat temperature probe? (If not one costing under £10 would be plenty good enough) best press the probe tip against the surface for a minute or two until it stabilises the foam insulation (if tricky maybe use a chunk of expanded polystyrene to hold it wedged in one position, the foam insulating from your hand). Or a plug-in electricity monitor costs around £12.
IR thermometer on Amazon is good to have for different purposes and in this case.
My question is what power cord is on the 156 to the wall and do you have a separate AC line feeding the 156? Interestingly I had a similar issue with well regarded LPS’s on my Chord TT2 and Mscaler. The LPS’s caused my Chord items to run very warm almost hot. Moved them on.
I do have a suggestion, try plugging in your 500 in the outlets of the 156 closest to the 156’s power cord.
I will add I’m not a fan of all of the coils and other bits inside the Puritan unit.
I’ve used Shunyata Research products for years with excellent results. The unit doesn’t get warm I’ve never had any components get overly warm unless they are supposed to. And the improvements in sound quality are unmistakable. I currently use a Denali S6000 v.2 with a Shunyata Alpha XC v.2 power cord to the wall.
Why/how could power cord choice have any effect on the 500’s temperature at idle (meaning power consumption at idle)?
Have you tried another power cord?
I am using their Ultimate Power Chord and I ordered a 5m one to make the socket far away from my brawn fraim
I mean power cord from the 500 dr to the powerblock. Just in case.
