Efforts to cool my amp some

[mloew1]

Hi guys, this may seem like a really dumb question, But would I be better off turning my sub volume up on the sub itself and then run Audessy calibration, my thinking is I have the volume turned about 1/4 on the sub right now, so my Onkyo amp would have to be pushing itself more to get the same power to the sub. I would think that the Onkyo amp would require less strain and run cooler by letting the sub amp do all the grunt work. And would Audessy calibration automatically cut the power some from the Onkyo when it sends its test sounds out. If this makes any sense.

 

[TLS Guy]

Hi guys, this may seem like a really dumb question, But would I be better off turning my sub volume up on the sub itself and then run Audessy calibration, my thinking is I have the volume turned about 1/4 on the sub right now, so my Onkyo amp would have to be pushing itself more to get the same power to the sub. I would think that the Onkyo amp would require less strain and run cooler by letting the sub amp do all the grunt work. And would Audessy calibration automatically cut the power some from the Onkyo when it sends its test sounds out. If this makes any sense.

Your Onkyo receiver sends no power at all to your sub however you set it.

The Onkyo provides a voltage amplified signal to the sub, not a power amplified one.

 

[mloew1]

Thank you I did not realize that, I was under the impression there was a separate amp that drove the sub. Thanks for educating me,

 

[j_garcia]

Are you saying your amp runs hot? From what I understand, recent Onkyos run hot. So unless it is shutting down, I wouldn't worry about it. Just be sure to give it at least 3-4 inches of air space above and 1-2 on either side and it should be OK.

 

[baniels]

This fan was popular among tx sr805 owners. It made a big difference for me. Plugged into the switched outlet so it turns on with the onkyo.

For mine the best location was the right rear corner.

 

[mloew1]

This fan was popular among tx sr805 owners. It made a big difference for me. Plugged into the switched outlet so it turns on with the onkyo.

For mine the best location was the right rear corner.

Thanks but my 806 does not have a switched outlet.

 

[baniels]

There are other solutions. Look up Smart Strip. Senses when you power on a particular device, then triggers other outlets to switch on.

Thanks but my 806 does not have a switched outlet.

 

[TLS Guy]

Are you saying your amp runs hot? From what I understand, recent Onkyos run hot. So unless it is shutting down, I wouldn't worry about it. Just be sure to give it at least 3-4 inches of air space above and 1-2 on either side and it should be OK.

Running hot is always bad. No good ever comes of it with solid state electronics, only premature failure. No exceptions.

 

[j_garcia]

Running hot is always bad. No good ever comes of it with solid state electronics, only premature failure. No exceptions.

This is 100% true, so what I mean by that is that users report them running "hot". Hot compared to what? Under what conditions? I don't know. A normal amplifier in a receiver will generate heat, period. The designers provide vents for the heat to escape and instructions on how to provide adequate cooling for it. I would like to believe that after this many years of designing receivers, these companies know how to design something that won't burn itself out in a year or two.

My PM7200 in class A mode generates a TON of heat and has two massive heat sinks to dissipate it. In AB mode, it gets no warmer than a typical receiver.

 

[TLS Guy]

This is 100% true, so what I mean by that is that users report them running "hot". Hot compared to what? Under what conditions? I don't know. A normal amplifier in a receiver will generate heat, period. The designers provide vents for the heat to escape and instructions on how to provide adequate cooling for it. I would like to believe that after this many years of designing receivers, these companies know how to design something that won't burn itself out in a year or two.

My PM7200 in class A mode generates a TON of heat and has two massive heat sinks to dissipate it. In AB mode, it gets no warmer than a typical receiver.

There are credible reports of these receivers all over the place running too hot to touch, despite adequate ventilation. That means the case is over 60 degrees C and the devices much higher. No device should run above 60 C if you want long life.

Now not all the receivers run hot, and this has to be a combination of the speakers impedance curves, phase angles, listening levels and the size of the listening space. However a receiver should not run too hot to touch, within its specified power range driving any speakers, as long as it has adequate ventilation.

Any device that can not achieve that is not worth building, let alone buying.

 

[j_garcia]

I agree, there is no real reason why a typical receiver should get hot to the touch. My 8300 rarely ever even got warm to the touch except after heavy hours of use. When I moved to 4 Ohm speakers, that changed and that's one of the reasons why I move to external amplification.

 

[TLS Guy]

I agree, there is no real reason why a typical receiver should get hot to the touch. My 8300 rarely ever even got warm to the touch except after heavy hours of use. When I moved to 4 Ohm speakers, that changed and that's one of the reasons why I move to external amplification.

Any device that can not drive 4 ohm speakers is not very useful. Most 8 ohm speakers are in fact really 4 ohm. In fact if the speaker is truly 8 ohm it is very unlikely that it is BSC compensated. To drive a decent system a device must be 4 ohm capable.

In fact all amplifying devices should be specked at four ohm. An 8 spec is actually not very useful in the real world now.

 

[j_garcia]

Any device that can not drive 4 ohm speakers is not very useful. Most 8 ohm speakers are in fact really 4 ohm. In fact if the speaker is truly 8 ohm it is very unlikely that it is BSC compensated. To drive a decent system a device must be 4 ohm capable.

In fact all amplifying devices should be specked at four ohm. An 8 spec is actually not very useful in the real world now.

Well, there's the general public and then there's Audioholics My speakers dip down no lower than 2.6 ohms and are fairly sensitive (91.5dB), but my previous and current rooms are quite large and I don't listen at low volume

 

[hizzaah]

I picked up one of these usb powered fans from amazon. Love it. I have it powered by the usb port on the back of my cable box.. I have it set to ~70% speed and it's silent. It's blowing air into the rear right corner of the receiver which is where I recorded the hottest temps with my IR thermometer gun.. That is also where the hdmi ports and I assume switcher is located so that is why I assume these newer models have gotten bad wraps for sketchy hdmi.

I didn't have a ton of space above my receiver, so this dropped me from ~40C to around 25C. Only down side is that the fan is always on, but I suppose it doesn't really matter as I can't hear it anyways lol. Now I have no problems running my receiver all day if I want.

 

[sholling]

There are credible reports of these receivers all over the place running too hot to touch, despite adequate ventilation. That means the case is over 60 degrees C and the devices much higher. No device should run above 60 C if you want long life.

Just out of curiosity I ran my 906 (145wpc) with a 5.1 channel BD movie at moderate levels for an hour yesterday to give it time to get it good and warm and then measured the temperature at between 98 and 113 F depending on where I measured. Today I tested with a 5.1 music source cranked up to LOUD and the temps went up to 114-128 F depending on the location. I'm sure it would climb with higher room temperatures but that was with 5.1 channel sources. That's in a spot with relatively poor ventilation. Because of where it's at I'll be adding fans to the cabinet.

 

[TLS Guy]

Just out of curiosity I ran my 906 (145wpc) with a 5.1 channel BD movie at moderate levels for an hour yesterday to give it time to get it good and warm and then measured the temperature at between 98 and 113 F depending on where I measured. Today I tested with a 5.1 music source cranked up to LOUD and the temps went up to 114-128 F depending on the location. I'm sure it would climb with higher room temperatures but that was with 5.1 channel sources. That's in a spot with relatively poor ventilation. Because of where it's at I'll be adding fans to the cabinet.

That would be 53 C. So you would not want it much hotter, before you have trouble. The trouble is, you don't know how hot the devices are to get the case that hot.

 

[mloew1]

These are all good points, and I think we can all agree that heat KILLS. I am positive that heat is what led to my Onkyo's early problems. Unfortunately for me my equipment is all custom built in, and can not reasonably be changed, so after I repaired my Onkyo I am now trying to give it a better second life. Like I said I have now raised my amp and given it 4-5" clearance on top.