Mini digital board amp inside a sealed enclosure?

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What are your thoughts on placing a digital amplifier board, say a 50x50W TPA3116 inside of a relatively small sealed speaker enclosure?
Assuming respectable SPL [levels] usage for an hour or so at a time.

1) No way, it'll burn out real fast.
2) Ehh, mebbe it'll be fine, maybe not.
3) Probably be just okay.
 
What are your thoughts on placing a digital amplifier board, say a 50x50W TPA3116 inside of a relatively small sealed speaker enclosure?
Assuming respectable SPL [levels] usage for an hour or so at a time.

1) No way, it'll burn out real fast.
2) Ehh, mebbe it'll be fine, maybe not.
3) Probably be just okay.

1. 50x50W=2500W :p
but 2 x 50W seems OK

Cheers ,

Rens
 

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  • TI TPA3116D2 datasheet scr.png
    TI TPA3116D2 datasheet scr.png
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There's a difference between a digital amplifier power stage and a digital amplifier. Please point to where you suppose the digital signal would come in or where you see an ADC in the chip block lay-out.

The TPA3116 is completely analog with an output stage that uses discrete levels (in the TPA3116 it is either binary or ternary) in the amplitude domain as most other class D amplifiers, it is still an analog amplifier though because the signal is pulse width modulated.
 
There's a difference between a digital amplifier power stage and a digital amplifier. Please point to where you suppose the digital signal would come in or where you see an ADC in the chip block lay-out.

The TPA3116 is completely analog with an output stage that uses discrete levels (in the TPA3116 it is either binary or ternary) in the amplitude domain as most other class D amplifiers, it is still an analog amplifier though because the signal is pulse width modulated.

see post #5

http://www.diyaudio.com/forums/clas...-amp-inside-sealed-enclosure.html#post4093977
 
Ok. Since you don't understand it then I'll briefly explain it. The error in the data sheet is the word amplifier. Where it says digital amplifier power stage, it should just have said digital power stage. Considering there are several quite serious factual mistakes in the data sheet, a small semantical error doesn't bother me too much.
And in a semiconductor company the marketing department writes the data sheet.

Of course the lines between digital and analog are pretty blurred in high speed circuits. Instead of using simplified logic gate models in high speed simulations, often the more accurate analog simulations are used to make sure the logic works at high speed.

That's much higher speed than a switching amp works at (GHz as opposed to maybe 10 MHz) and a great deal of the chip is devoted to the power device and gate driver which are very analog.

Some amplifiers can legitimately claim digital operation. I think Tripath has digital feedback or something. Others that are ~pure analog still have control logic that doesn't interact with the signal at all.

Without seeing an accurate block diagram its hard to make a distinction.
 
Some amplifiers can legitimately claim digital operation. I think Tripath has digital feedback or something.

A (pure) digital amplifier cannot have feedback. The very presence of feedback means it is not a (pure) digital amplifier as the feedback is taken from an analog source, ie. the output, it has to be AD converted back into the control logic which means that the amplifier is controlled by analog signal and therefore cannot claim to be a (pure) digital amplifier.
 
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A (pure) digital amplifier cannot have feedback. The very presence of feedback means it is not a (pure) digital amplifier as the feedback is taken from an analog source, ie. the output, it has to be AD converted back into the control logic which means that the amplifier is controlled by analog signal and therefore cannot claim to be a (pure) digital amplifier.

First of all - why not just answer the question (note that the question was not about digital amplifier definitions)

Second. DDFA claims the feedback to be digital

DDFA® - Direct Digital Feedback Amplifier Technology
 
Ok. Since you don't understand it then I'll briefly explain it. The error in the data sheet is the word amplifier. Where it says digital amplifier power stage, it should just have said digital power stage. Considering there are several quite serious factual mistakes in the data sheet, a small semantical error doesn't bother me too much.

Get back to me after you contact TI.
 
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