[mfer]

See this pic?

I would guess it is the left side of this picture with the white stick on top or am I wrong? The capacitors make some (middle red). Can anyone confirm? Thanks.

 

[bagwell359]

Power output transistors which should be mounted on heat diffusing metal (probably arranged in fins or to maximize surface area). That's for SS amps. Sometimes there is not enough air flow. Fans used sometimes. Punching grid holes in the external cover etc. Or removal of cover. That opens the amp to RFI. So a cage replacement works too.

Many Class A amps have this concern. Some Class AB. Other classes I know are pretty trivial to cool.

 

[bagwell359]

That thing is a power supply. Usually they don't throw lots of heat. Can't see behind it and output transistors could be there.

 

[gimmeheadroom]

Every component through which power passes generates heat.

The power transformer has to deal with more power than the rest of the circuit so it sheds the most heat. Other major pieces that deal with heat are power transistors, opamps, power-supply caps, tubes, etc.

 

[mfer]

Thanks for replies. I just ordered this one. I asked b/c the heat vent is above the right side, but I just assumed looking at this picture the heat comes from the left. I'll guess I'll find out soon enough.

The negative about this amp is the heat it generates. I'll find a way to cool it. I like things cool, don't know why. I have some old parts around that I could likely use. Might be a fun project.

 

[Dogmatrix]

See this pic?


I would guess it is the left side of this picture with the white stick on top or am I wrong? The capacitors make some (middle red). Can anyone confirm? Thanks.

To the right of the red caps you can see a partially obscured black square there is another one behind the black cap
They are the output transistors , being class A means they run full power all the time so any power you are not consuming is dissipated as heat
Amps like this will run coolest when they are working hardest

 

[mfer]

To the right of the red caps you can see a partially obscured black square there is another one behind the black cap
They are the output transistors , being class A means they run full power all the time so any power you are not consuming is dissipated as heat
Amps like this will run coolest when they are working hardest

Thanks for that tidbit. I have some extra thermal pads and a heat sink that might help those then. I'll have to see if I can cut down the old heat sink. Then it is just air flow and regular cleaning.

But before any of that I'll see hot it performs and take some relative laser thermometer readings.

 

[ozz]

The one in the picture is an A3 which will run warm if you want to talk about hot the original A1 was a small space heater ,I have the A3 for over a year now and it has never run hot warm yes .

 

[mfer]

The one in the picture is an A3 which will run warm if you want to talk about hot the original A1 was a small space heater ,I have the A3 for over a year now and it has never run hot warm yes .

Good for the winter.

Cant wait to get it. Maybe a week or so. Thanks for reply compared to original Asgard.

 

[bagwell359]

Thanks for that tidbit. I have some extra thermal pads and a heat sink that might help those then. I'll have to see if I can cut down the old heat sink. Then it is just air flow and regular cleaning.

But before any of that I'll see hot it performs and take some relative laser thermometer readings.

I would not cut any heat sinking away! If you add to it and it's out away in the open it will help but it must be mated firmly to the existing heat sink. Also do not put the unit in a narrow/tight space. It needs to be in the open. Might help to open up the bottom of the unit via a number of small holes about 1/4" in diameter adjacent to the transistors for improved air flow and decreased resale.

Some amps are designed to work with average internal temps of 120-150 F. Many of those are Class A due to the real issue if heat dissipation. I had a Bedini 25/25 that ran at about 185 F making my Rag 1 seem cool by comparison.

All the class A amps I know have output transistors that ran a lot hotter than the power supply. Like 2nd degree burn hot.

 

[mfer]

No I wouldn’t remove any heat sink, rather add one I have. It is likely too big however. I’ll see when I get the item. They make cpu fans that are less than 2” so it could fit likely.

 

[Nimzerz]

These amps are typically designed to operate at those temperatures. Cooling them down might put them outside of their optimal operating range.

 

[Dogmatrix]

These amps are typically designed to operate at those temperatures. Cooling them down might put them outside of their optimal operating range.

When I looked into this there was quite a bit of evidence cold is not an issue with transistors also hot is not really an issue unless the ventilation is obstructed in which case the caps will die first

 

[Nimzerz]

When I looked into this there was quite a bit of evidence cold is not an issue with transistors also hot is not really an issue unless the ventilation is obstructed in which case the caps will die first

It is not an issue from a reliability standpoint. But for sound quality, it is.

 

[mfer]

Been running the amp most of the day. It is NOT hot at all. All the reviews say this thing is a space heater. It would barely be a coffee warmer at these temps, I'm seeing 22F over ambient per my thermometer.

ath-r70x 470ohm being used.