Literally all of the modern Class D designs from B&O (ICE Power) and Bruno Putzeys. I have a pair of PS Audio stereo amps based on the OLD B&O ICE Power 200ASC that have never failed, shut down, blipped or otherwise misbehaved. I leave them on 24/7 and they've seen heavy stereo and home theater use over the years. ICE Power modules are used WIDELY in both professional and consumer applications.
By using 5mm thermal pads under those amp and power supply FETs they are reducing the life expectancy and the low impedance drive capability of those class D amps. Don't get me wrong in that I support class D amps for all the right reasons but the previous and maybe current models with their bent PCBs and 5mm thermal pads using a minimum of screws for clamping are not low impedance capable and they are failing and will be failing due to this cheaping out on assembly. Rather than follow car audio's class D lead with high integrity heatsink clamping and thermal dissipation via heavy duty heatsinks the home audio amp makers are making junk that will not last due to heat.
LoL.
Not sure of @restorer-john' opinion on this but he has or had class D amp and power supply PCBs that have fried FETs due to bad heatsink clamping? The recent test of class D amp and power supply combo by @thin bLue resulted in a fried power supply and that was maybe heatsink clamping issues too. I've seen dozens of images of the clamping assembly and method of class D amp and power supply PCBs where the board was bent over due to the lack of tight tolerance in the assembly of PCB, FETs and heatsinking method used. I've repaired thousands of class A with PWM power supply car audio amps and they used a clamshell clamping arrangement like the new class D amps are using and the issues where veryyy plentiful. I wanted to drop the line as I was the Canadian warranty service depot for that brand of car amps because they where expecting too much from me in fixing their rubbish. It's a very cheap way of assembling but it's ridden with issues and failures.
My 10 year-old Rotel RMB1565, that is hidden inside a cabinet, "has the ICEpower modules for its class D operation".
NAD M22.
Actually that’s not the leading hypothesis (based on info from a knowledgeable source who will be doing an autopsy of the aforementioned power supply).
Purifi 1ET7040SA (see earlier post of how it is handling reference level usage with sub 1ohm impedance swings from the LCR speakers).
It appears to be a quality Rotel although there's something fishy with the specs. Rated @ 4 Ohms minimum.My 10 year-old Rotel RMB1565, that is hidden inside a cabinet, "has the ICEpower modules for its class D operation".
In operation 24/7 and probably nearing ten-thousand hours of operation.
This Apollon or a BuckEye maybe be strong contenders if my Rotel decided to go on retirement.
Yes, I speculated and I might be right too. The clamping is atrocious.
Whatever happened,it should shut down,plain and simple.
The test results at Stereophile are hardly linear or good. Nor do they indicate good low impedance drive capability.
www.stereophile.com
You want me to go smell inside the cabinet? I am guessing it was born fishy?
Earlier post? I have no idea where that is located. You might be opening a pandoras box because if that's the thread where I calculated the min impedance drive to be ~3 Ohms and then confirmed it at the data sheet to be ~3.2 Ohms that might be counterproductive. I checked the data sheet today and at the amp's Max 40A output at even the lowest possible voltage it outputs ~700 Watts RMS @ 0.9 Ohms. It's good but there is significant roll-off of the power output. Again I have doubts about the heatsink clamping integrity and there is a nanny circuit monitoring the amp and power supply operating conditions to compensate for this lack of low impedance drive capability. There seems to be lots of commentary around my doubts and I want to make sure that you are aware that I like and support class D but I am not going to give them low impedance drive ratings because I have not seen that proven yet or actually tested. All I have seen are failures when tested or operated that way. For a real solid test they need to drive less than 2 Ohms and do it into loads with a proper soak test and not a blip of a test sine wave etc and then they can compete with the big boys that do drive low impedances.
Depending on which test result used that impedance swings down to ~3 or maybe ~4.25 Ohms and that's right in line with the class D offerings lower limit. ~3 Ohms seems to be about the state of class D affairs. Most speakers don't go lower I admit and this has been the bane of many a commentary here at ASR. But to deserve the real low impedance drive backing they have to actually do it and not claim it with numbers games and stretched figures.You want me to go smell inside the cabinet? I am guessing it was born fishy?
View attachment 310652
2 channels of the Rotel run the woofers, 2 others for mid/tweeters (1 channel for a center).
Can you link me to the link?
