Ventilation space on pedalboard with FM9

[stm113]

I am starting to put together a pedal board for jamming and some gigs. Beside of my FM9 I have an expression and a whammy. Since the unit vents to the side, how much space you reckon I need to leave for proper heat venting and to not overheat the unit?

 

[bleujazz3]

It's suggested that at least an inch space between devices (expression pedals, effects, etc) on either side the FM9 is adequate. Some choose greater distance, but 1-inch is adequate...also be sure your fan intake vent underneath isn't blocked. A perforated board is acceptable, as is a slat space board.

 

[Rex]

I am starting to put together a pedal board for jamming and some gigs. Beside of my FM9 I have an expression and a whammy. Since the unit vents to the side, how much space you reckon I need to leave for proper heat venting and to not overheat the unit?

Good question. I tend to agree with @bleujazz3’s suggestion of at least an inch. But, to my knowledge, Fractal has never stated a specific amount of spacing. I suspect it depends on air temperature, heat generated by other equipment, which way the wind is blowing...

 

[bleujazz3]

Good question. I tend to agree with @bleujazz3’s suggestion of at least an inch. But, to my knowledge, Fractal has never stated a specific amount of spacing. I suspect it depends on air temperature, heat generated by other equipment, which way the wind is blowing...

Thanks for vouching for me. My feeling is that unless other devices generate heat themselves, the 1-inch distance is adequate. I don't know of any other device that might do that, except tube or active electronic devices. Expression pedals and analog/digital effects aren't about to generate significant heat themselves, unless there's some need for heat dissipation.

What @Rex said about air temperature, and perhaps surface reflectivity, might play a role. If air temp were a factor, you might consider augmenting your fog generator or light show with a room fan to help keep things cool...I do know that when you've got bright lights, you'll need some heat dissipation somewhere...

 

[Greg Ferguson]

From the FM3's Wiki page about its Manufacturing, which applies to the FM9 also…

"There's only so much heat you can dissipate in a small chassis. Add to that the requirement for harsh environments (outside, on a hot day in direct sun) and you have to be careful. There actually is a fan in the unit but it's controlled by a thermostat and under normal conditions it doesn't run. Reliability is paramount in a product like this. You can't have it shutting down during a performance." [8]

"The fan speed is temperature dependent. Be sure to not block the vents on the sides or the fan intake on the bottom. At room temperature the fan will rarely turn on." [11]

"The DSP is NOT designed for a heat sink and doesn't need one." [12]

(firmware 1.05) "The fan now operates at different thresholds than when the ambient temperature was used. It should now spin up at 60°C, switch to high speed at 70°C, and turn off when the temperature drops below 55°C. Also note that on-screen temperature readings may be different than those you may have become accustomed to seeing when the ambient temperature was being measured." [13]

Here's my $.02:

Both the FM3 and the FM9 have exhaust vents on the ends. Don't block them. I've used about 1/2" between my FM3+FC6 on the board and never heard the fan come on except at power-up, which I attribute to having two vents and well-designed passive cooling with the forced-cooling backup.

60ºC/140ºF is not something we're going to see indoors in any normal situations, and even outdoors in direct sunlight it's hard to hit that unless we're in Death Valley, at which point we should hear the fan kick in. My FM3 has been running for several days, and I've been beating it pretty badly lately, and have never heard the fan, and, the vent is barely warm.

If the unit is going to sit outdoors in the sun I'd put something white or reflective over it when I'm not using it, something like a reflective windshield sunshade. I think of it this way, if it's hot enough to get the unit to turn its fan on, it's too hot for me to be in the sun. Cliff WAY over-engineers the units so I wouldn't be paranoid about it, just be sensible.

 

[ezvictor]

Is there a temp limitation that we should be aware of?
I see 60c/140f from the post above but if the temp is not regularly in our scan, how are we supposed to know when to allow for a cool down? And how long should we allow the unit to cool?

 

[Greg Ferguson]

Is there a temp limitation that we should be aware of?
I see 60c/140f from the post above but if the temp is not regularly in our scan, how are we supposed to know when to allow for a cool down? And how long should we allow the unit to cool?

You are overthinking it. The fan will handle it if you get above 140ºF. If it hits 170ºF, which is well on its way to boiling water, you'll hear the fan because it's pretty obvious at that point, and can react to it.

And, if it hits the point the fan is running at high-speed? Let it run until the fan slows down or stops.

 

[stm113]

You are overthinking it. The fan will handle it if you get above 140ºF. If it hits 170ºF, which is well on its way to boiling water, you'll hear the fan because it's pretty obvious at that point, and can react to it.

And, if it hits the point the fan is running at high-speed? Let it run until the fan slows down or stops.

So the distance of the right angle plug that will be between my whammy and the side of the unit should be fine then?

 

[Greg Ferguson]

So the distance of the right angle plug that will be between my whammy and the side of the unit should be fine then?

I think so. That’s about 1/2” depending on the type of plug.

The manual says:

Keep away from sources of heat such as ducts, registers or appliances that produce heat.
Do not obstruct or cover over the side or bottom ventilation holes.

The bottom vent needs to be free of anything that would impede airflow. The two side vents help exhaust the heated air because heat rises.

Here’s an easy experiment; place them side by side at the proposed distance apart and turn them on and let them run for several hours while playing through them, and see if the fan turns on. I expect it will only turn on during boot-up. If the fan turns on while you are playing and increases in speed then it’s getting warm so separate them further and see if the fan slows down and stops. Because you are monitoring the situation you can make adjustments in their distance or turn it off.

Finally, remember this:

"The DSP won't get damaged if it overheats, it will just stop working. I've yet to see a unit overheat. Our products are overdesigned." [8]