Multi-channel Amp,Which one you would like to own?

[antcollinet]

I disagree. In this specific case, radiators arranged this way will require horizontal ventilation (i.e., forced ventilation... with a fan).

Your explanation seems completely irrational to me. I've opened hundreds of amplifiers... and I've never seen anything like it...

(my bold)

not if the cooling in it's current form keeps the devices cool enough. That can only be determined by detailed thermal tests which I am assuming has been done by the manufacturer.

 

[Guddu]

I disagree. In this specific case, radiators arranged this way will require horizontal ventilation (i.e., forced ventilation... with a fan).

Your explanation seems completely irrational to me. I've opened hundreds of amplifiers... and I've never seen anything like it...

It’s totally fine in expressing how you think the best modular arrangement is, and there is surely scope to agree to disagree.
Such modular arrangement isn’t new, like:

If the amplifier could operate with it without any issues then it should be totally acceptable.
You might like it horizontally placed but that would be your preference, not necessity.

PS. Apologies for putting a different vendor image in this 3e product thread, normally I avoid it.

 

[Mamocel]

(my bold)

not if the cooling in it's current form keeps the devices cool enough. That can only be determined by detailed thermal tests which I am assuming has been done by the manufacturer.

The TPA 3255 gets quite hot at 48V... So with 5 cards in the same case... A temperature-controlled fan would have been a good idea.

 

[Mamocel]

It’s totally fine in expressing how you think the best modular arrangement is, and there is surely scope to agree to disagree.
Such modular arrangement isn’t new, like:
View attachment 524811

If the amplifier could operate with it without any issues then it should be totally acceptable.
You might like it horizontally placed but that would be your preference, not necessity.

PS. Apologies for putting a different vendor image in this 3e product thread, normally I avoid it.

In your photos, the cooling plates are smooth... so they don't impede convection at all.

 

[antcollinet]

The TPA 3255 gets quite hot at 48V... So with 5 cards in the same case... A temperature-controlled fan wouldn't have been a good idea.

Cooling design is complex and sometimes counterintuitive. I used to run project teams developing high power industrial drives for motors (from a few hundred watts, up to hundreds of kilowatts) We used Finite Element Analysis software to model airflow and cooling prior to prototyping - even then real world results sometimes made up their own mind about how they would work.

Bottom line - detailed thermal testing with thermocouples on devices measuring their actual temperature (and/or thermal cameras) is the only way to verify how well cooling really works.

You certainly cannot look at a design from a picture, and state anything at all definitive regarding whether or not it is good enough.

 

[Mamocel]

You certainly cannot look at a design from a picture, and state anything at all definitive regarding whether or not it is good enough.

No... But it gives us some clues... Ah, variators, I repair quite a few of them... almost all of them forced air.

 

[antcollinet]

variators,

No, VSDs (using similar switching tech to class D amps). And the lower power models (ratings similar to an audio amp) try to avoid forced air cooling.

 

[Mamocel]

No, VSDs (using similar switching tech to class D amps). And the lower power models (ratings similar to an audio amp) try to avoid forced air cooling.

Yes, IPM module...IGBT and inductor filtering before the motor...

 

[john61ct]

I've opened hundreds of amplifiers... and I've never seen anything like it...

That doesn't mean this design will not work

 

[Mamocel]

That doesn't mean this design will not work

But it gives us some clues...

 

[antcollinet]

Clues are not enough to state

"It will require....."

In fact - all the evidence that is available to us (a released working product) is that it doesn't require.

 

[Mamocel]

In fact - all the evidence that is available to us (a released working product) is that it doesn't require.

We'll talk about it again....Let time pass.

 

[john61ct]

“It is impossible for a man to learn what he thinks he already knows”

– Epictetus

 

[Mamocel]

If you are convinced... Ignore my posts.

 

[john61ct]

No, in fact I eagerly await your points based on evidence rather than "because I am an expert, I am right" appeal to authority

 

[Roland68]

The TPA 3255 gets quite hot at 48V... So with 5 cards in the same case... A temperature-controlled fan would have been a good idea.

In TPA3255-based amplifiers, most of the heat is not generated by the TPA3255 chip itself, but by the often inefficient 12V power supply and the generation of the supply voltage for the op-amps.
This power dissipation is often many times greater than that of the highly efficient TPA3255 at idle and in the lower power range.
TPA3255-based amplifiers run significantly cooler with a lower voltage or an external 12V supply; this has been known in development circles for a long time. And this has nothing directly to do with the TPA3255 chip.

 

[john61ct]

I need every dB/watt output, have a 48V lithium power bank that I plan to convert to ~52V for my 3e amps.

I am confused by your 12V comment.

I assume converting from 12V to my desired 46V+ (no AC nor grid power involved) would not have any such impact on running cooler.

I never heard of running 12V directly into these amps.

Can you explain what you mean?

 

[Roland68]

I need every dB/watt output, have a 48V lithium power bank that I plan to convert to ~52V for my 3e amps.

I am confused by your 12V comment.

I assume converting from 12V to my desired 46V+ (no AC nor grid power involved) would not have any such impact on running cooler.

I never heard of running 12V directly into these amps.

Can you explain what you mean?

The TPA325x chips require an additional 12V supply, which is generated from the high supply voltage.
This also requires a supply voltage for the op-amps, which is somewhere in the 12-24V range (or +/- 6-12V).
Many manufacturers implement this very inefficiently, resulting in significant power loss as heat.

But you don't need to worry about that with 3E Audio; their devices are all well-designed, and it's very rare that I have nothing to complain about. They use very efficient and high-quality circuitry for their voltage generation.

 

[john61ct]

thanks for clearing that up

 

[antcollinet]

We'll talk about it again....Let time pass.

If there is new evidence, sure. But bear in mind, someone putting their hands on the case and saying "oh, it's a bit warm" (or looking inside and opining) is not that.