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Apollon Hypex NC2K Monoblock Amplifier Review

audioBliss

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@ audiobliss Because you used a 20db headroom . That's why. Do you know what is a 20db headroom ? that is about of 6 times the power you have available.
That is why I asked.
I would think that this would mean that the source material played has a crest factor of 20dB? I have 400W right? And playing a piece of music at 85dB average and that music happens to have 20dB crest factor I would need about 700W is what I get from the calculator(so in this scenario I would need a bigger amp). But I typically don't listen above 80dBA average and during that scenario I only need 200W. I am not sure what your point is? I was merely playing around with the thought of adding more power.
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P.s. I.e. the reason you would want that headroom is because you are listening to well mastered source material with a high crest factor.
 

audioBliss

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I have a piece of music with around 30dB crest factor and in that case peak power of 2kW would be need in my case with average 80dB listening level...If I'm understanding the calculator correctly. But yeah that would be pretty loud..110dBA at the seating position when the music peaks. A bit too loud for my taste actually and lowering the average volume to 75dB would "only" need 6-700W in this case.
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But then again most good recordings maybe only has 15dB crest factor in which case I only need 20W with 75dB average level. So maybe my nc400 are perfect as they are. Even with movies played at -10dBFS I only need 60W apparently so maybe all is good ;)
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dfuller

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andreasmaaan

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There's little to explain. Of course.
Normal is normal as normal , ie something that appears quite often . Most is something that appears more frequently than normal.
If you search, some new speakers specs , they state 90db anechoic 93db average room.
I don't rely on Stereophile"s measurements , since there isn't a term as average sensitivity in my vocabulary. As there isn't an analogue term in power amplifier"s power.
Average , I'm sure you know is a function of mathematics , just to compare some values that can not be compared otherwise.
Or anyway , a method of taking a mid point reference , for no reason.
Well it’s just getting petty now (both our faults) :)

Still, I can’t resist getting the final word in: most speakers fall below the average (the distribution is positively skewed).

Apologies in advance...
 

andreasmaaan

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I have a piece of music with around 30dB crest factor and in that case peak power of 2kW would be need in my case with average 80dB listening level...If I'm understanding the calculator correctly. But yeah that would be pretty loud..110dBA at the seating position when the music peaks. A bit too loud for my taste actually and lowering the average volume to 75dB would "only" need 6-700W in this case.
View attachment 88730 View attachment 88731

But then again most good recordings maybe only has 15dB crest factor in which case I only need 20W with 75dB average level. So maybe my nc400 are perfect as they are. Even with movies played at -10dBFS I only need 60W apparently so maybe all is good ;)
View attachment 88732 View attachment 88733
Keep in mind that the critical distance in most living rooms is 1 to 1.5m. So if you enter this distance into the calculator, it will give you a more accurate approximation of the power required to reach a given SPL at any distance greater than the critical distance.
 

617

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Keep in mind that the critical distance in most living rooms is 1 to 1.5m. So if you enter this distance into the calculator, it will give you a more accurate approximation of the power required to reach a given SPL at any distance greater than the critical distance.
Perhaps I'm missing something but can you explain this in greater detail?
 

PeteL

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I would think that this would mean that the source material played has a crest factor of 20dB? I have 400W right? And playing a piece of music at 85dB average and that music happens to have 20dB crest factor I would need about 700W is what I get from the calculator(so in this scenario I would need a bigger amp). But I typically don't listen above 80dBA average and during that scenario I only need 200W. I am not sure what your point is? I was merely playing around with the thought of adding more power.
View attachment 88728

P.s. I.e. the reason you would want that headroom is because you are listening to well mastered source material with a high crest factor.
May I ask where to find this calculator? Looks handy.
 

andreasmaaan

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Perhaps I'm missing something but can you explain this in greater detail?
Once you exceed the critical distance (distance at which SPL of the direct sound = SPL of reflections), moving further away from the speakers has little effect on the total SPL.

Imagine your critical distance is 1m. Let’s say you measure 90dB here, where (by definition) the contribution from the direct sound will be 50% and the contribution from reflections also 50%. These two are mostly uncorrelated, so let’s oversimplify a bit and say that direct sound is contributing 87dB and reflected sound 87dB (SPL[direct] + SPL[reflected] = 10log10(10^(SPL[direct]/10)+10^(SPL[reflected])/10))).

The calculator does not account for reflections, so even at the critical distance we already have a gap of 3dB, that is, the calculator predicts 87dB, whereas the (closer to) reality is that we will get 87dB from the direct sound + 87dB from reflections = 90dB.

Now imagine moving back to 2m. The contribution from the direct sound will drop to 81dB (slightly oversimplifying by assuming the inverse square law perfectly applies, which is true only if the speakers are omnidirectional), while the contribution from reflected sound remains at 87dB (slightly oversimplifying by assuming a reverberant field - which is true only on average).

81dB + 87dB = 88dB (vs 81dB using the simple inverse square law used by the calculator).

Now do the same calculation at 4m, and:

75dB + 87dB = 87.3dB (vs 75dB using the simple inverse square law).

And so on..

Indeed, no matter how far one listens/measures from the sound source, the total SPL will (on average) never drop more than 3dB below the level it is at the critical distance, which is already going to be around 3dB above what the calculator predicts (give or take, depending on whether the critical distance is more or less than 1m).
 
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Vasr

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Internally it looks quite respectable for sure. The exterior leaves a bit to be desired. Panels gaps and bends visible on the rear. Certainly not remotely good enough for a multi thousand dollar amplifier...


View attachment 88628

There's no bracing for the rear panel at all and no central screws for the top or bottom panels. It wouldn't pass muster at a Japanese manufacturer.
Sheesh, you are like the dude who goes to a NASCAR event and points out that the doors of the cars are misaligned that would never be acceptable to a German/Japanese manufacturer. ;)

This is the redneck, hilly-billy, male bro looking for sheer power (to compensate for what is open to debate) equivalent of audio. Vibrates a bit more at 350hp output? Who cares.
 

dfuller

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Sheesh, you are like the dude who goes to a NASCAR event and points out that the doors of the cars are misaligned that would never be acceptable to a German/Japanese manufacturer. ;)

This is the redneck, hilly-billy, male bro looking for sheer power (to compensate for what is open to debate) equivalent of audio. Vibrates a bit more at 350hp output? Who cares.
Not really... These amps cost $2000+ for a monoblock. I expect better than this kind of build quality for that kind of scratch.
 
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