Some amplifier related doubts

[madhukannan]

Hi
which type of these resistors are good for making load bank ? and which values are ideal for testing upto 500w amplifiers ( aluminum ones are available in 4 , 8, 2 ohm 100W silicon coated ones in any value . )

or

 

[madhukannan]

What should be the minimum thickness of L clamps to connect to3 device to the main heatsinks? will three mm clamp be sufficient ( for class A )

 

[lgreen]

I used the first type in My Krell output stage.
The assembly gets very hot but working fine for 10 years and counting... 60 to 70C normally.
Not sure what you mean for L clamps for TO3

 

[jan.didden]

Hi
which type of these resistors are good for making load bank ? and which values are ideal for testing upto 500w amplifiers ( aluminum ones are available in 4 , 8, 2 ohm 100W silicon coated ones in any value . )
View attachment 1326319 or View attachment 1326320

Any value will work as long as the combination is correct the load you want to simulate.
THe 50W alu are available in 80 ohms so 10 in parallel will give you 8 ohms with 500W capability.

Be aware that the 50W rating is only when they are at 25 Celcius.
As they heat up, you need to derate the rating, so it pays to use a huge heatsink.
500W continuously is a LOT of heat and needs serious heatsinking and a fan.
If you test with short measurements of a few tens of seconds the heatsink requirement can be relaxed.

Jan