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Apollon NCx500ST Stereo Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 3 0.8%
  • 2. Not terrible (postman panther)

    Votes: 4 1.0%
  • 3. Fine (happy panther)

    Votes: 30 7.6%
  • 4. Great (golfing panther)

    Votes: 357 90.6%

  • Total voters
    394

wavetrade

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Have wondered if I was losing some fidelity having the dac volume control under -30db. Your question gives me some optimism that maybe not.

I was also a little worried about accidentally changing my dac from preamp mode to dac mode mid song with the remote. The remote would of allowed this with one wrong click when toggling through the settings. Thankfully the DO300 I just got does not make it as easy to change modes using the remote.
 

AkodoGilador

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Because of these graphs, right?

1700551320661.png


Alex
 

antcollinet

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Because of these graphs, right?

View attachment 328207

Alex
Right, but this is the simple result of fixed noise level in reducing signal. 20dB reduction in signal= aprox 20dB loss in Sinad (actually SNR)

So if noise is inaudible when no music is playing, (or even when music is playing at the -30dB volume reduction) - it is inaudible, and reduction in volume doesn't matter.
 

antcollinet

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Have wondered if I was losing some fidelity having the dac volume control under -30db. Your question gives me some optimism that maybe not.

I was also a little worried about accidentally changing my dac from preamp mode to dac mode mid song with the remote. The remote would of allowed this with one wrong click when toggling through the settings. Thankfully the DO300 I just got does not make it as easy to change modes using the remote.
1 - See my reply to @AkodoGilador above.

2 - If you are hearing audible noise from the DAC with no music playing, and the gain steps of the amp are too large, you could put a passive attenuator pad on the input of the amp, slected to still allow the maximum volume you will ever want to play with the DAC at 0dB.
 

Julf

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So if noise is inaudible when no music is playing, (or even when music is playing at the -30dB volume reduction) - it is inaudible, and reduction in volume doesn't matter.
This.
 

AkodoGilador

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Ok, that leads to two reasons to desire the use of a lower gain level in the amplifier, right?
  1. The DAC's noise will be amplified more by a higher gain.
  2. The amplifier itself generates more noise at higher gain levels.
Alex
 

Julf

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Ok, that leads to two reasons to desire the use of a lower gain level in the amplifier, right?
  1. The DAC's noise will be amplified more by a higher gain.
  2. The amplifier itself generates more noise at higher gain levels.
Alex
Indeed. If neither causes audible noise, there is no issue.
 

antcollinet

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Ok, that leads to two reasons to desire the use of a lower gain level in the amplifier, right?
  1. The DAC's noise will be amplified more by a higher gain.
  2. The amplifier itself generates more noise at higher gain levels.
Alex
Correct.

But both of these are answerd by the question:

"Can you hear the noise at the listening position with music silenced, with your desired gain?"

If not, then reducing the gain is not necessary.

The less stringent question: "Does the noise bother you when listeing to music at your normal listening level?" can also be used.


Anecdote alert.

In my system which is combined audio from PC and Home Theater, there is a slight audible whine from the speakers when nothing is playing.

It bothers me that it is not perfectly silent. I could probably spend a day or two tracking down the reason and eliminating it.

But since I cannot detect that at all when even quiet audio is playing, I am pragmatic enough to accept that it is un-necessary to fix.
 

Overseas

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Usually I listen at night, when - at this time of the year - my wood heating installation produces a clearly audible noise (the electrical pumps). Plus the fridge, the damn' invertor that squeeks at times. So, what would be the motivation to pay for a performant system with zero noise...

Agreed, at the same price, I will prefer the best engineering.
 

Julf

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antcollinet

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Don't amps with high power and this distortion level sound better at low volume listening levels?

The amp doesn't care.


If the speakers or room or your ears can't take the power, then yes, it is going to sound better at lower volumes.
 

soerenssen

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Is it possible to connect one side of this stereo amp to the HF and the other side to the LF terminal of one speaker?
I'm considering this because in the LS60 (which is very similar to mine) KEF decided to use 3 separate amps for tweeter/mid/woofers, but I'm not sure what one would gain with this. The other option would be to bridge the same amp and just connect it to the lower terminals.
 

Julf

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KEF decided to use 3 separate amps for tweeter/mid/woofers, but I'm not sure what one would gain with this.
It only makes sense if you can use an active crossover (and avoid the traditional passive crossover).
 
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