PC Case for amplifier

[salesmonster]

Has anyone used an old PC case for an amplifier enclosure? The amp intended for the enclosure will require a large-ish heatsink and cosmetics aren't important for this project. Is there a simple way to attach a heatsink to the outside sides of the case, and still have an efficient thermal transfer?

SM

[planet10]

I haven't done it yet, but i have a growing number of Apple G4 & G5 tower cases that i intend to use for amps some days. The G5 cases are aluminum. The G4 cases would need to have internal sinks (or be used for tube amps)

dave

[nigelwright7557]

Originally Posted by salesmonster

Has anyone used an old PC case for an amplifier enclosure? The amp intended for the enclosure will require a large-ish heatsink and cosmetics aren't important for this project. Is there a simple way to attach a heatsink to the outside sides of the case, and still have an efficient thermal transfer?

SM

I have done this twice.
I used the desktop rather than the tower to keep things flat but also allow a flat top for a mixer.

The PC case can utilise its power input socket and fan mountings which is great.

I stripped out the power supply and used its mains socket.

PC cases are good and solid and make good audio enclosures.

[CBRworm]

I have considered using a small desktop PC case with fairly good front to back airflow (single 120mm quiet fan) and putting all the heat sinks inside. I could make everything much more compact - just need to make sure overtemp protection works in case of fan failure, etc.

[nigelwright7557]

Originally Posted by CBRworm

I have considered using a small desktop PC case with fairly good front to back airflow (single 120mm quiet fan) and putting all the heat sinks inside. I could make everything much more compact - just need to make sure overtemp protection works in case of fan failure, etc.

Make sure you use high air flow fans.
I got caught out with the small flow fans and my amp over heated.
So I put one high flow fan on the front and another on the rear of the case.
The fans with LED's insdie them look very good.

[Craig405]

PC cases could potentially be ok for an amp, just not the cheap ones, the aluminium would almost certainly bend under the weigh of heavy transformers.

As for heatsinking power transistors to the case I would have thought this is a bad idea for class A or high powered amplifiers as the aluminium is just so thin, even though theres a lot of surface area you will get big hotspots under the devices.

Mounting a heatsink to the other side of the aluminium to make it external to the insides as I believe you enquired about could improve this situation, but you end up with another thermal juncton to overcome which will reduce the heat transferred to the heatsink itself.

The best solution would be to cut away a portion of the PC case and bolt your transistors straight through to a large externally mounted heatsink, this way you get the pc case for your circuits and the advantage of good heatsinking.
And as others mentioned mounting the heatsink inside the case could also work very well if you use the ventilation and fan mounts of the case to bring enough air inside and remove it again.
Although with fans comes dust and with dust comes heat and eventually smoke

This amp will be one ugly SOB though.. no two ways about it!


With further thought actually a barebones shuttle case could offer a very nice solution as they are smaller in size, nicer to look at and most importantly come with a neat passive heatpipe cpu cooling solution integrated that can handle a fair bit of power dissipation.. with good air flow added this could be a very feasable solution.. hmm.

[nigelwright7557]

Originally Posted by Craig405

As for heatsinking power transistors to the case I would have thought this is a bad idea for class A or high powered amplifiers as the aluminium is just so thin, even though theres a lot of surface area you will get big hotspots under the devices.

hmm.

I mounted a large heatsink on the inside and blew air through it with a fan at the front and the back. But you need decent fans with a good airflow for this to work well. You could even add a third fan that blew air through the heatsink to be sure of a good flow.

[Craig405]

check this out for the shuttle thing:

http://images.google.co.uk/imgres?im...a%3DN%26um%3D1

you could drill in a good few T0220 or similar devices into the plate and use the funky heatpipe solution, all in a nice, solid, neat case.

[sandyK]

http://www.siliconchip.com.au/cms/A_102322/article.html

[nigelwright7557]

Originally Posted by sandyK

http://www.siliconchip.com.au/cms/A_102322/article.html

That looks very neat.

I have built two, both in desktop cases so the large mixer goes on top neatly.
One is 600WRMS and the other 800WRMS.