Re: CPU style cooling ?
i want to clear up some common misconceptions here first...
cooling CPU's is a WHOLE different thing. when you say that we keep our chips "cool", you are kinda understating the fact... a chip generates a WHOLE lot of heat. more than you could imagine. if you had a chip with full load on it, and removed heatsink, within 2 seconds it would reach 600F. thats a LOT more demand than FETs. the chip can get SO hot so quick, it is capable of melting itself, and runing the entire motherboard.
secondly, you are MORE than right about halfing the power of the fans. i run most of my computer fans at 7V, instead of the 12V (i just cross the 12v and 5v lines). even at 7v they are very efffective, AND, almost silent. this is how my watercooling fans worked.
and, like anything else, some fans are better than others. i use panaflo fans. they blow a good amount of air, and are very quiet. plus, my case has sound insulation... if fans are to be used to cool water, they could be enclosed in such a way to minimize sound. dynamat and others work well. however, in comparison, i ONCE AGAIN dont think amps create as much heat as we think. will an uncooled amp actually MELT itself within 2 seconds from the intense amount of heat generated? there is almost NO way for a current computer CPU to be run WITHOUT active cooling... its an option for amps, but for a CPU, its just not even possible.
im not really sure what im going to do once i get the cash to spend on this project, but it will be the last phase. but i DO know that it will be a contained solution, and i want it to look as if its just another audio component, just with HUGE interconnects 🙂
the lake is a great idea, BUT, it makes things messy. plus, that water would ruin your system after awhile. turbulence is the highest factor in an effective heatsink/waterblock. the more turbulence, the better heat transfer. murky water would clog the waterblocks, and create lessened flow. this would hurt the pump (possibly making it fail due to excessive strain), make the waterblocks less effective, and possibly cause leaks due to back pressure.
watercooling is nice, but for every TINY detail, there are like 50 others that you cant even think of. why do you think its not used in any consumer electronics? the idea is simple, but its very hard to make it a "portable" and scaleable solution. i want to make watercooling setup that is expandable to new components, and upgradeable. i have some designs, but unfortunately, no time to really work on anything. hopefully i will ditch my current job and get the job at the audio store that i want 🙂 well, wish me luck on the phone interview tomorrow!
i want to clear up some common misconceptions here first...
cooling CPU's is a WHOLE different thing. when you say that we keep our chips "cool", you are kinda understating the fact... a chip generates a WHOLE lot of heat. more than you could imagine. if you had a chip with full load on it, and removed heatsink, within 2 seconds it would reach 600F. thats a LOT more demand than FETs. the chip can get SO hot so quick, it is capable of melting itself, and runing the entire motherboard.
secondly, you are MORE than right about halfing the power of the fans. i run most of my computer fans at 7V, instead of the 12V (i just cross the 12v and 5v lines). even at 7v they are very efffective, AND, almost silent. this is how my watercooling fans worked.
and, like anything else, some fans are better than others. i use panaflo fans. they blow a good amount of air, and are very quiet. plus, my case has sound insulation... if fans are to be used to cool water, they could be enclosed in such a way to minimize sound. dynamat and others work well. however, in comparison, i ONCE AGAIN dont think amps create as much heat as we think. will an uncooled amp actually MELT itself within 2 seconds from the intense amount of heat generated? there is almost NO way for a current computer CPU to be run WITHOUT active cooling... its an option for amps, but for a CPU, its just not even possible.
im not really sure what im going to do once i get the cash to spend on this project, but it will be the last phase. but i DO know that it will be a contained solution, and i want it to look as if its just another audio component, just with HUGE interconnects 🙂
the lake is a great idea, BUT, it makes things messy. plus, that water would ruin your system after awhile. turbulence is the highest factor in an effective heatsink/waterblock. the more turbulence, the better heat transfer. murky water would clog the waterblocks, and create lessened flow. this would hurt the pump (possibly making it fail due to excessive strain), make the waterblocks less effective, and possibly cause leaks due to back pressure.
watercooling is nice, but for every TINY detail, there are like 50 others that you cant even think of. why do you think its not used in any consumer electronics? the idea is simple, but its very hard to make it a "portable" and scaleable solution. i want to make watercooling setup that is expandable to new components, and upgradeable. i have some designs, but unfortunately, no time to really work on anything. hopefully i will ditch my current job and get the job at the audio store that i want 🙂 well, wish me luck on the phone interview tomorrow!
mefinnis said:
Actually most CPU's dissipate less than 100W of heat, it is the small size of the package that necessitates the use of active cooling. Many of our Class-A monsters dissipate many 100's of watts but generally less than 20W per output device which allows us to use somewhat extreme passive cooling. Finally liquid cooling is used in some consumer electronics.
Member
Joined 2002
Coulomb is right a cpu is totaly difrent than a fet a cpu ( amd Brand ) will rize it's heat verry verry fat a fet takes a bit of time and will not burn out like a cpu a apu will get hot in mater of seconds and burn out and melt and the short and blow apart. inlike a fet.
Oldschool athlons (thunderbirds) could put out up to 200w of heat (that was pushed pretty hard). But now with smaller dies they run cooler. But cowanrg if you remove the heatsink from a cpu the heat has nowhere to go so the temperature rises. The alephs use multiple devices and multiple (large) heatsinks to dissipate that much heat. Have you ever hooked up a giant 10lb heatsink to a cpu and see how well it cooled passively? Well I have, ain't too much of a problem really (on an athlon), ran warm but nothing burned of melted. "there is almost NO way for a current computer CPU to be run WITHOUT active cooling" seems a little exagerated since I've done it before and know of a guy who ran heat pipes from his cpu to a substantial heatsink outside his case, and it ran well, no need for forced air cooling...
Just to say, don't underestimate the heat produced by these bad boys because you think cpus put out alot more heat...
An interesting fact though, crey (or is it cray? oh well) supercomputers used to use liquid cooling (do believe it was water, only makes sense to be) to cool themselves down. Not sure about todays models though. Sure they're not really consumer, but...
Just to say, don't underestimate the heat produced by these bad boys because you think cpus put out alot more heat...
An interesting fact though, crey (or is it cray? oh well) supercomputers used to use liquid cooling (do believe it was water, only makes sense to be) to cool themselves down. Not sure about todays models though. Sure they're not really consumer, but...
It's been discussed
Grey Rollins has at least one thread all about his water cooled Aleph. Search and read it- it's worth it People have mentioned all the objections there, and he has answered them all. He doesn't use a fan, algae growth and clogging discussed to death.
THE BEST PART is Grey's way of attaching the Mosfets to the water hoses, A simple, cheap plate of copper-no machined water block. There is no doubt that an Aleph will burn up mighty fast without lot's of cooling-it's no option!!! Water cooling with junk parts is the cheapest way to go, the pump is the only thing that might take a bit of work to find free. You can test the amp by running water from the tap through it as a full loss system, without a radiator.
You use a lake to cool by putting a loop of hose or pipe IN it.
You don't pump the lake water in.
Grey Rollins has at least one thread all about his water cooled Aleph. Search and read it- it's worth it People have mentioned all the objections there, and he has answered them all. He doesn't use a fan, algae growth and clogging discussed to death.
THE BEST PART is Grey's way of attaching the Mosfets to the water hoses, A simple, cheap plate of copper-no machined water block. There is no doubt that an Aleph will burn up mighty fast without lot's of cooling-it's no option!!! Water cooling with junk parts is the cheapest way to go, the pump is the only thing that might take a bit of work to find free. You can test the amp by running water from the tap through it as a full loss system, without a radiator.
You use a lake to cool by putting a loop of hose or pipe IN it.
You don't pump the lake water in.
Back to CPUs please !
Reasoning behind the 1 FET Aleph5 idea .....
Aleph 5 = 150W/channel = 75W each for the I-source and ouput FET, if we used just 1 device instead of 3.
My AMD produces about 100W as stated above and the chip T is about 32C with the fan running at full power. Our FET can get a lot warmer than this!
Haven't done the sums, but I'd estimate if you put 1 CPU fan per FET (2 / channel) with the fans at 1/2 speed you'll probably be in the "ball-park".
This would save on FET matching 🙂
Higher current per device = better distortion.
Problems arise in the power supply for the fans (x4) and isolating these from the amp PS, but this can be done. Agree, you would line the case to minimize transmitted noise.
Can't get it out of my head ...... think it might be quite neat 😉
cheers, mark
Reasoning behind the 1 FET Aleph5 idea .....
Aleph 5 = 150W/channel = 75W each for the I-source and ouput FET, if we used just 1 device instead of 3.
My AMD produces about 100W as stated above and the chip T is about 32C with the fan running at full power. Our FET can get a lot warmer than this!
Haven't done the sums, but I'd estimate if you put 1 CPU fan per FET (2 / channel) with the fans at 1/2 speed you'll probably be in the "ball-park".
This would save on FET matching 🙂
Higher current per device = better distortion.
Problems arise in the power supply for the fans (x4) and isolating these from the amp PS, but this can be done. Agree, you would line the case to minimize transmitted noise.
Can't get it out of my head ...... think it might be quite neat 😉
cheers, mark
I think it would work great and look very cool. You could try different voltages while measuring the temp near the mosfet to get the correct fan speed. As you say, they are quite efficient, so maybe could be run very slowly. I was tempted awhile back by some surplus CPU heatsinks that were for an older cpu style. I think they were $3 apiece. I want to make Aleph 2 monoblocks, so that would be 12 fans per monoblock!! Total cost under $75.
Try it and post a picture!!
Try it and post a picture!!
sound is very complicated... especially when dealing with fans.
i had an idea similar to that once for cooling some electronics. however, a bunch of fans together creates a lot of noise.
im not sure of the ranges off the top of my head, but i think around like 30dB is a whisper. 40 is like normal volume talking.
now, you are talking about 12 fans right? most good fans are around 30dB, BARELY audible if the amp is enclosed. however, the difference between 30dB and 31dB would be 2 of your fans. dB is measured logarithmically. meaning, (roughly), to gain a single dB, you double your sound. so, if you have 12 30dB fans, your end result would be 42dB, aroudn that of a person talking normal volume. thats LOUD. i had a 45dB fan once, and it was VERY annoying.
the best idea is to have as few fans as possible... maybe 2 34dB fans blowing across the heatinks... but 12 fans, (unless they are VERY VERY low dB), would be really loud any way you slice it.
i had an idea similar to that once for cooling some electronics. however, a bunch of fans together creates a lot of noise.
im not sure of the ranges off the top of my head, but i think around like 30dB is a whisper. 40 is like normal volume talking.
now, you are talking about 12 fans right? most good fans are around 30dB, BARELY audible if the amp is enclosed. however, the difference between 30dB and 31dB would be 2 of your fans. dB is measured logarithmically. meaning, (roughly), to gain a single dB, you double your sound. so, if you have 12 30dB fans, your end result would be 42dB, aroudn that of a person talking normal volume. thats LOUD. i had a 45dB fan once, and it was VERY annoying.
the best idea is to have as few fans as possible... maybe 2 34dB fans blowing across the heatinks... but 12 fans, (unless they are VERY VERY low dB), would be really loud any way you slice it.
cowanrg said:
Twice the average acoustical power is a net 3dB increase, twice the inphase acoustical power is 6dB increase. Also good 80mm fans are 12dB although obviously the smaller diameter fans will generate high dB levels due to the higher RPM required.
Makes sense. A speaker twice as loud is 3db higher. Of course it doesn't sound twice as loud-just somewhat louder, since our ear seem to be logrithmic. Also twice as many fans can be run at half the speed so it gets complicated
OK, more heatsinks less fans, but bigger and slower
OK, more heatsinks less fans, but bigger and slower
another thing to consider about those 80mm fans that are 12dB, they cant be pushing that much air at ALL. a SLIGHT breeze is like 8cfm, and anything that small that quiet, must only be around 12cfm.
plus, air turbulence through a heatsink causes sound too. the fan alone may be quiet, but when you blow through a heatsink, it gets noisier.
plus, air turbulence through a heatsink causes sound too. the fan alone may be quiet, but when you blow through a heatsink, it gets noisier.
I think the quietest is a tunnel for cooling. Two heatsinks with the fins toward eachother and the fans one in front of the tunnel and one at the end. Use the fans at half speed and you hace a lot better cooling.
When the fans are in the air or just blowing on a heatsink this is not so good because you dont have 100% air floa on the heatsink.
In a closed system where 100 % of the air flow goes through the heatsink fins you have a lot better results and is a lot quieter.
When the fans are in the air or just blowing on a heatsink this is not so good because you dont have 100% air floa on the heatsink.
In a closed system where 100 % of the air flow goes through the heatsink fins you have a lot better results and is a lot quieter.
- Status
- Not open for further replies.