I know it is not usually nor widely done but that does not mean it is bad , or can not be a good option. Provided one´s case allows for the space and the used CPU-cooler fits nicely inside then : WHY NOT ? I would like to start a thread on this subject , using a nice chip-amp ( TDA7293 ) which needs a very good and efficient heatsink. These things are big and bulky anyways , apart from quite expensive as well , and if they are in the range of a degree/w of less than 1,5 they oblige to use a rather high case , see the Dissipante series casings .
I like to get "the most" out of things so that applies to chip-amps as well. To achieve a case which is of low height , say up to 3 inches =# 7,5 cms , and which fits in with other "normal" hihi-gear blending in with it is not easy at all having to use traditional large radiators.
Which brings me to the use of suitable CPU-coolers. Heatpipe-versions can easyly get rid of 100 watts or more od heat and come in all shapes and sizes so as an example have a look at this one :
Compatible CPU: Intel and AMD
Heatsink Material: Copper & Aluminum
Product weight: 1 Fan 410g 2 Fan 480g
Type: 2 Heat pipe TDP: 100W Fan
Size: 90x90x25m
This thing ( only as an example ) is under 17 dollars at Ali-express and is about 3 inches in thickness including the fan which can be taken off and either be substituted by 4 smaller 2" fans which would reduce the height by 1,5 cm ( 3/5 of an inch ) or by placing two fans at the back of casing channeling air to back side , using 2 2" fans side by side (intake from bottom in both cases ) . see here :
https://www.aliexpress.us/item/3256804444035466.html?spm=a2g0o.productlist.main.47.24f950afi1KlID&algo_pvid=de44c6f0-a3c9-46fb-be7f-f2aaf11d2e10&aem_p4p_detail=202301240544064528510827017250020440333&algo_exp_id=de44c6f0-a3c9-46fb-be7f-f2aaf11d2e10-23&pdp_ext_f={"sku_id":"12000029911056072"}&pdp_npi=2@dis!EUR!29.34!17.61!!!!!@2145280e16745678462392948d0708!12000029911056072!sea&curPageLogUid=QSRSNuH17WDz&ad_pvid=202301240544064528510827017250020440333_24&ad_pvid=202301240544064528510827017250020440333_24&gatewayAdapt=esp2usa4itemAdapt&_randl_shipto=US
I would love to resd lots of your opinions here .
I like to get "the most" out of things so that applies to chip-amps as well. To achieve a case which is of low height , say up to 3 inches =# 7,5 cms , and which fits in with other "normal" hihi-gear blending in with it is not easy at all having to use traditional large radiators.
Which brings me to the use of suitable CPU-coolers. Heatpipe-versions can easyly get rid of 100 watts or more od heat and come in all shapes and sizes so as an example have a look at this one :
Compatible CPU: Intel and AMD
Heatsink Material: Copper & Aluminum
Product weight: 1 Fan 410g 2 Fan 480g
Type: 2 Heat pipe TDP: 100W Fan
Size: 90x90x25m
This thing ( only as an example ) is under 17 dollars at Ali-express and is about 3 inches in thickness including the fan which can be taken off and either be substituted by 4 smaller 2" fans which would reduce the height by 1,5 cm ( 3/5 of an inch ) or by placing two fans at the back of casing channeling air to back side , using 2 2" fans side by side (intake from bottom in both cases ) . see here :
https://www.aliexpress.us/item/3256804444035466.html?spm=a2g0o.productlist.main.47.24f950afi1KlID&algo_pvid=de44c6f0-a3c9-46fb-be7f-f2aaf11d2e10&aem_p4p_detail=202301240544064528510827017250020440333&algo_exp_id=de44c6f0-a3c9-46fb-be7f-f2aaf11d2e10-23&pdp_ext_f={"sku_id":"12000029911056072"}&pdp_npi=2@dis!EUR!29.34!17.61!!!!!@2145280e16745678462392948d0708!12000029911056072!sea&curPageLogUid=QSRSNuH17WDz&ad_pvid=202301240544064528510827017250020440333_24&ad_pvid=202301240544064528510827017250020440333_24&gatewayAdapt=esp2usa4itemAdapt&_randl_shipto=US
I would love to resd lots of your opinions here .
First possible issue is fan noise. You might want a temperature based controller for the fan speed, adding complexity.
Second issue is reliability. Fans do wear out and fail, you might want to use some kind of rpm monitoring if the chip amp is not fully thermally protected.
Other than that I don't see why this shouldnt work.
Second issue is reliability. Fans do wear out and fail, you might want to use some kind of rpm monitoring if the chip amp is not fully thermally protected.
Other than that I don't see why this shouldnt work.
Use the biggest heat sink and the biggest mains powered fan that will fit the housing.
Most amp housings are 85% free space or more by volume, so air circulation will not be a problem.
I would prefer a passive setting, fans are needed only if there is a space constraint, which is rarely encountered.
And you are making it for yourself, so I wold not use such complex cooling solutions.
You rarely need that much power in a home.
In concerts and so on, yes. But those units sell less than 5% in numbers of total sales.
Most amp housings are 85% free space or more by volume, so air circulation will not be a problem.
I would prefer a passive setting, fans are needed only if there is a space constraint, which is rarely encountered.
And you are making it for yourself, so I wold not use such complex cooling solutions.
You rarely need that much power in a home.
In concerts and so on, yes. But those units sell less than 5% in numbers of total sales.
I have a Marshall 100 watt chip amp guitar amplifier that uses a CPU heat sink and fan.
I bought it as faulty as fan was very noisy (bearings gone.)
It was an easy fix.
I bought it as faulty as fan was very noisy (bearings gone.)
It was an easy fix.
I see no reason a CPU cooler and a quiet fan wouldn't work for audio. There are some fan options out there that only produce single digit dB(A) SPL when they're running. Just don't drill into the heat pipes...
Tom
Tom
If you can,. try to find old CPU heatsinks used in AMD64 OR Pentium D PCs , mfg around 2004-2008 . Those were some really heavy heatsinks. Post 2009, AMD X2 OR Core2Duo came with much lighter and skimpier heatsinks. You may need some sort of "Tapping bit" for screws
junior35 - those Dell 3500 (?) extruded heatsinks are very stylish and pleasing to look at compared to thin fin variety. There's a lot of "5" at Ebay for $24.95 shipped as I write.
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Fan cooling is quite normal in the Musical Instrument world, because they are supposed to be run at highest power for hours in poor environments, think Club stages and such.
Nigel shows a classic example.
Obviously in that setting (fan) noise is not a problem.
Personally,, I use enough heatsinking ("enough", not "overkill") and improve both its functioning plus general chassis temperature by adding a lowered speed fan, which still moves air around but does not create a "whistle".
Say, a plain vanilla 12V fan, fed 9V or used with a series resistor to drop some voltage.
Noise becomes inaudible.
Nigel shows a classic example.
Obviously in that setting (fan) noise is not a problem.
Personally,, I use enough heatsinking ("enough", not "overkill") and improve both its functioning plus general chassis temperature by adding a lowered speed fan, which still moves air around but does not create a "whistle".
Say, a plain vanilla 12V fan, fed 9V or used with a series resistor to drop some voltage.
Noise becomes inaudible.
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Fantastic amount of answers in only a day - Thanks to all of you.
The fans , if well chosen , are no problem at all where noise is concerned . I have 2" and 2,4" ( 7cm) fans which run at 6 volts are as good as totally silent , after all they only need to substitue the air between the fins before it gets hothot no storm needed.
Fans could actually be off until needed with a small cheap controller-board as heatpipes work even without it ,o start them at 40 degress + for example .
Main reasons for the type of cooler shown in my first post is TDP of 100W , sufficient even for hot chip-ams like LM3886 and TDA7293 at high rails, after all cpu´s must be kept below 60 to 70 degrees ,
and the fact that with a careful design one can keep the amps case at 2,5" only , because the heatpipe system allows for spreading the heat out horizontally and keep things flat , and the added "bonus" of being cheap in comparison .
Of course one must mount the cooler without drilling holes in it , best to use pressure instead of holes 🙂 or the existing screws some way.
I am searching for the best and most efficient heatpipe cooler at up to 20 dollars / euros , just to experiment and see what can be done
😉
The fans , if well chosen , are no problem at all where noise is concerned . I have 2" and 2,4" ( 7cm) fans which run at 6 volts are as good as totally silent , after all they only need to substitue the air between the fins before it gets hothot no storm needed.
Fans could actually be off until needed with a small cheap controller-board as heatpipes work even without it ,o start them at 40 degress + for example .
Main reasons for the type of cooler shown in my first post is TDP of 100W , sufficient even for hot chip-ams like LM3886 and TDA7293 at high rails, after all cpu´s must be kept below 60 to 70 degrees ,
and the fact that with a careful design one can keep the amps case at 2,5" only , because the heatpipe system allows for spreading the heat out horizontally and keep things flat , and the added "bonus" of being cheap in comparison .
Of course one must mount the cooler without drilling holes in it , best to use pressure instead of holes 🙂 or the existing screws some way.
I am searching for the best and most efficient heatpipe cooler at up to 20 dollars / euros , just to experiment and see what can be done
😉
You should add a 75-85C thermal switch to heatsink.
Protects both from (VERY unusual) fan failure and far too easy vents blocking (some idiot dropping his jacket on top of amp or similar) or lint buidup.
Protects both from (VERY unusual) fan failure and far too easy vents blocking (some idiot dropping his jacket on top of amp or similar) or lint buidup.
I have no issues with a TDA7293 mounted on a cpu heatsink.
Hardly any heat for background music.
If one is driving the amp hard, use a fan with a thermal switch on the heatsink as JM suggested.
Hardly any heat for background music.
If one is driving the amp hard, use a fan with a thermal switch on the heatsink as JM suggested.
Thanks for the heads up.
I have more than 100pcs of TDA7293 and 7294. Original ST.
Bought them about yr 2000.
Only decided to design some kits with them a few months ago.
I have more than 100pcs of TDA7293 and 7294. Original ST.
Bought them about yr 2000.
Only decided to design some kits with them a few months ago.
Yes of course one would have to add a thermal switch just in case . I would use two chips in parallel for high current ability and halving thermal load on them , on a copper strip 100x30x4mms so the thermal can go in between them . The heatpipes work all the time anyways so up to 30 or 40 % of power no fan should be necesary at all .That way no overtemp-protection kicking in .
It is a matter of experimenting to see what happens as this is something new to me . For the time being i have ordered the cooler and two heavy load 4 ohm resistors to start the trials with no risk to blow any chips.
cooler is in post 1 , and resistors are 4 ohm 25w from Mouser ,
https://www.mouser.es/ProductDetail/Vishay/RHA0254R000FE02?qs=sGAEpiMZZMtlubZbdhIBIPSEYpw2e3wdNVDp/1yvvPM=
This will allow me to get exact data with dissipation up to 50 w , see how this performs in reality both with and without fan or fans . 18v transformer onto the resistors will give me 40 constant watts
It is a matter of experimenting to see what happens as this is something new to me . For the time being i have ordered the cooler and two heavy load 4 ohm resistors to start the trials with no risk to blow any chips.
cooler is in post 1 , and resistors are 4 ohm 25w from Mouser ,
This will allow me to get exact data with dissipation up to 50 w , see how this performs in reality both with and without fan or fans . 18v transformer onto the resistors will give me 40 constant watts
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Heat pipes are high conductivity transfer devices, the side dispersing the heat from the component must be in a place where convection heat transfer can take place in without fan working, at lower temperatures.
An idle fan can block a lot of the area of the place from which heat is to go to the atmosphere.
Please bear this in mind.
Also, larger fans turn slower for the same flow of air, so lower noise levels, Noctua are said to be very quiet.
That was why I said put the largest fan that will fit.
See the charts for the fans, Noctua is one of many makers, Papst is also well known, I have no ties to anybody named.
Papst also makes a line of CPU cooler like devices for cooling LEDs used in high output devices like street lights and stadium lights, they may have competitors in that segment also.
An idle fan can block a lot of the area of the place from which heat is to go to the atmosphere.
Please bear this in mind.
Also, larger fans turn slower for the same flow of air, so lower noise levels, Noctua are said to be very quiet.
That was why I said put the largest fan that will fit.
See the charts for the fans, Noctua is one of many makers, Papst is also well known, I have no ties to anybody named.
Papst also makes a line of CPU cooler like devices for cooling LEDs used in high output devices like street lights and stadium lights, they may have competitors in that segment also.
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