Best way to cool an amplifier mounted inside a subwoofer cabinet?

[cat]

In this sound system, Sony shoved the entire amp for the whole setup inside the subwoofer cabinet, and it powers both the subwoofer and the passive soundbar speakers.

There's a wooden panel below the amp where it sits on, which appears to separate the electronics area from the main subwoofer chamber.

Inside the amp chamber:

• The hottest parts are the long vertical amplifier heatsink on the left and the row of output inductors next to it.

• The cabinet only has tiny vent holes on the back (right).

• The left side (where most of the heat is generated) has no vents.

I'm trying to add active cooling with a strong fan to extend the life of the amp.

Questions:

1. What is that rectangular plastic thing likely for if it's not for wires to come through?

2. Would drilling ventilation holes on the top panel of the cabinet (directly above the amp chamber) affect the subwoofer acoustics?

3. What would be the best airflow setup for cooling this amp?

 

[cat]

Inside the amp chamber there's also a rectangular plastic opening that leads somewhere into the cabinet. At first I thought it might connect to the front bass port tunnel, but I played some bass tracks and couldn't feel any air coming through that opening.

Also worth mentioning: the speaker wires that go down to the woofer do NOT pass through that opening. Instead they come from the side edge of the panel, almost like a very small groove or gap was made along the panel edge just for the wires to pass through.

 

[staticV3]

2. Would drilling ventilation holes on the top panel of the cabinet (directly above the amp chamber) affect the subwoofer acoustics?

As long as you do not compromise the structural rigidity of the cabinet, no it would not.

3. What would be the best airflow setup for cooling this amp?

I'd leave the cabinet intact and see if there's enough space on the left half of the I/O plate to mount a Noctua NF-A4x20 in exhaust orientation, so that it sucks in air from the vents on the right half and circulates it across the heat sinks.

You could mount and control it externally, or given that you have the qualifications to work on Mains powered electronics, you may be able to find a 5V/12V output on the PCB to mount and power the fan internally.

All this of course only if the increased cooling is even required.

 

[Roland68]

In this sound system, Sony shoved the entire amp for the whole setup inside the subwoofer cabinet, and it powers both the subwoofer and the passive soundbar speakers.

There's a wooden panel below the amp where it sits on, which appears to separate the electronics area from the main subwoofer chamber.

Inside the amp chamber:

• The hottest parts are the long vertical amplifier heatsink on the left and the row of output inductors next to it.

• The cabinet only has tiny vent holes on the back (right).

• The left side (where most of the heat is generated) has no vents.

I'm trying to add active cooling with a strong fan to extend the life of the amp.

Questions:

1. What is that rectangular plastic thing likely for if it's not for wires to come through?

2. Would drilling ventilation holes on the top panel of the cabinet (directly above the amp chamber) affect the subwoofer acoustics?

3. What would be the best airflow setup for cooling this amp?

Sony usually does a good job with these kinds of devices.

What temperatures do the amplifier's heat sinks reach during operation, and what temperature does the casing reach at the hot spot?

Furthermore, these are Class D amplifiers. With these devices, the switching frequencies have a much greater impact on lifespan than heat. Switching them off when not in use is many times more effective than cooling, which may not even be necessary or desirable.
I've already written about the recurring heat hysteria here #150 and here #18.

 

[cat]

I'd leave the cabinet intact and see if there's enough space on the left half of the I/O plate to mount a Noctua NF-A4x20 in exhaust orientation, so that it sucks in air from the vents on the right half and circulates it across the heat sinks.

im a little confused about the fan placement you mentioned

the left half of the back panel on my unit is basically a solid plate with no vents so how would the fan actually move air there would that mean cutting a hole and mounting the fan there

if thats what you meant then yeah that was kinda what i was thinking too but theres still warranty left on this thing and it was a pretty big investment for me so i aint trying to rawdog the system like that yet

im trying to keep any mods minimal or reversible for now at least until the warranty expires

 

[DVDdoug]

You could pull the amp out and mount it in a separate box/cabinet. ...But depending on how the speaker wires are attached you might void the warranty extending them.

 

[tineared]

I would leave it alone and hope the Sony engineers designed it properly
If you don't have that confidence, then don't buy it or sell it if you already bought it and pick another brand
Is this just a mental exercise or do you have reason to believe there is a problem with the design?

 

[cat]

You could pull the amp out and mount it in a separate box/cabinet. ...But depending on how the speaker wires are attached you might void the warranty extending them.

yeah thats actually exactly what i was thinking at first

but then i realized there are like three wires coming through from the sub to the amp and they're those small 4 wire pin type connectors not just normal wires

if it was just two regular wires id probably just extend them and run the sub from the amp outside the box but with those connectors and the sensitive cables id probably end up messing something up lol

 

[cat]

I would leave it alone and hope the Sony engineers designed it properly
If you don't have that confidence, then don't buy it or sell it if you already bought it and pick another brand
Is this just a mental exercise or do you have reason to believe there is a problem with the design?

its not really that i think theres a design flaw or anything its more of a curiosity thing after opening it up and seeing how everything is packed in there

i dont have any actual failure or issue right now it works perfectly fine i just noticed that one side of the amp section gets pretty warm during longer use so it got me thinking about airflow and cooling in general

so yeah mostly a mix of curiosity and thinking about long term longevity. one thing ive always heard across electronics is that heat slowly degrades components over time

so from a long term perspective i just figured a bit of extra airflow might help longevity even if its not strictly necessary

 

[Steven Holt]

Just had my coffee, trying to wake up....and I come across this. DON'T DO ANYTHING, LIVE WITH IT AS SONY DESIGNED IT. Any modification will void the warranty. Sony engineers know what they are doing. Have you read any reviews, anywhere, that says this is a problem?

 

[cat]

Just had my coffee, trying to wake up....and I come across this.

lmao

it was mostly curiosity after opening it up and noticing that one side of the amp section gets pretty warm during longer use so it got me thinking about airflow and cooling in general

i havent actually seen any reports of failures or overheating issues with it so yeah for now im probably just gonna leave it as is or just add a fan on the existing holes

 

[staticV3]

would that mean cutting a hole and mounting the fan there

if thats what you meant then yeah that was kinda what i was thinking too

That's what I meant

 

[Steven Holt]

That's what I meant

Static, I think you meant 'I'm gonna try to fix this guy's problem but he really doesn't have one but what the hell it's a slow day anyway....'

 

[staticV3]

Static, I think you meant 'I'm gonna try to fix this guy's problem but he really doesn't have one but what the hell it's a slow day anyway....'

Maybe read first

All this of course only if the increased cooling is even required.