Yamaha M-60 vs M-65

[sherin]

I have a Yamaha M-65 and recently picked up an M-60 and noticed that the transformer runs hotter in the M-60 than the M-65, is this normal or should I be concerned?
It gets to the point that I can't hold my hand directly on the transformer.

 

[KingBubba]

I have an M65 and was surprised at how cool it stays, even in class A mode. I have no experience with the M60. I don't really push this amp very hard, I don't need to.

 

[avionic]

Is it the power transformer or the heatsinks that are emitting the heat.If its the heatsinks are you running in "class A". If yes its normal, If no the bias on the output transistors may be a little to high. Generally transformers don't heat up very much unless your really pushing it.

 

[sherin]

I have an M65 and was surprised at how cool it stays, even in class A mode. I have no experience with the M60. I don't really push this amp very hard, I don't need to.

The M-60 runs about the same temp as the M-65 over the heat sinks it's just the transformer that runs hotter.

 

[sherin]

Is it the power transformer or the heatsinks that are emitting the heat.If its the heatsinks are you running in "class A". If yes its normal, If no the bias on the output transistors may be a little to high. Generally transformers don't heat up very much unless your really pushing it.

It is the power transformer, the heatsinks are just warm. It can be just at an idle for a few hours and it heats up more than the M-65.

 

[tubed]

I dont have the M-65, however I'm presently powering my 4 ohm ADS l-810's with an M-60. I notice no difference in heat where the transformer and heat sinks are located...volume at the 11:00 position for the last half hour. I did have a M-50 that ran very hot as opposed to my "cool" M-60.

 

[sherin]

I just want to get an idea if there is a problem with it or not, it has been on for the past 3 days from morning until night and seems to be working fine other than the transformer getting so hot.