Apollon NCx500ST Stereo Amplifier Review

[kchap]

Placed my order last night for the ST version. I am going to pair with Topping D90III Sabre. https://www.toppingaudio.com/product-item/d90-iii-sabre

Can anyone suggest if I should be choosing XLR 4V out on the Topping and Lowest gain on the Apollon to achieve the best technical outcome?

Topping says: "In addition to the more universal XLR 4V and RCA 2V outputs, the D90 III
SABRE also adds XLR 5V and RCA 2.5V.
When XLR 4V and RCA 2V are selected, more devices can be adapted. When XLR 5V and RCA 2.5V are selected, the performance will be
pushed from extreme to more extreme."

What happens if I select XLR 5V on topping , should the Apollon be set to medium gain settings?

Speakers are M&K sound S300 - max rated power 500w @ 4ohms.

I assume you have a volume control somewhere in the playback chain. If that is the case I would select a setting that can overdrive the amp by 6 to 15 dB. There is a wide variation in in he original recording levels. For newer recordings the volume control will set to lower gain while older recordings will more gain.

With D90 set for 5V out you need a voltage gain of 19dB for an output of 500W @ 4Ω. Based on my previous paragraph I would set the amp gain to 29dB

 

[sandeep_s300]

I assume you have a volume control somewhere in the playback chain. If that is the case I would select a setting that can overdrive the amp by 6 to 15 dB. There is a wide variation in in he original recording levels. For newer recordings the volume control will set to lower gain while older recordings will more gain.

With D90 set for 5V out you need a voltage gain of 19dB for an output of 500W @ 4Ω. Based on my previous paragraph I would set the amp gain to 29dB

Apollon audio replied to me - they said to set the XRL volt to 5v for maximum dynamics from the DAC and set the hypex ncx500 at medium gain 20.5 for the best outcome .

 

[Matias]

I would choose a low level song as a worst case, like some classical music, use the lowest gain on the amp, highest output voltage on the DAC, and start increasing the volume the loudest I can stand. If the DAC maxes out the volume, then I would use the 2nd lowest gain on the amp, etc. This way only the minimum gain needed is used on the amp.

 

[sandeep_s300]

I would choose a low level song as a worst case, like some classical music, use the lowest gain on the amp, highest output voltage on the DAC, and start increasing the volume the loudest I can stand. If the DAC maxes out the volume, then I would use the 2nd lowest gain on the amp, etc. This way only the minimum gain needed is used on the amp.

I would choose a low level song as a worst case, like some classical music, use the lowest gain on the amp, highest output voltage on the DAC, and start increasing the volume the loudest I can stand. If the DAC maxes out the volume, then I would use the 2nd lowest gain on the amp, etc. This way only the minimum gain needed is used on the amp.

Confused with the measurements of the hypex amp. Lowest gain had better SND whereas medium gain had better dynamic bit range. Amir I believe was also recommending the lowest.

 

[kchap]

"There is now such thing as a free lunch". I am quoting wildly out of context but what I am suggesting is setting the gain to min gives the best SINAD figure, but moves the problem down stream. The DAC/pre-amplifer must be capable of delivering 10~12V RMS. That may give an overall improvement of 2~3dB in SINAD but it's like the old theological discussion of how many angels can dance on the head of a pin. To us mortals it makes no difference.

I have a pair of March Audio P451 amps containing Purifi modules, gain fixed at 26.5dB driven by a Topping D10 balanced DAC. My sister has a pair of Apollon NCx500Ms, gain set to 29dB driven by a Wiim Amp PRO+ (unbalanced). On my slightly older March Audio amps I hear a faint hiss if I place my ear next to the tweeters. The Apollons are "quiet as the grave".

 

[mike70]

Somebody have the packaging size of this amplifier ?

 

[kchap]

Somebody have the packaging size of this amplifier ?

I can't remember the dimensions, but the UPS documents the weight of 2 x NCx500M was 4kG. They were shipped from Apollon.

 

[mike70]

I can't remember the dimensions, but the UPS documents the weight of 2 x NCx500M was 4kG. They were shipped from Apollon.

ok, but the package is far bigger than the amp or something with some foam and a box just a little bigger? (maybe i can take it on board in a flight?)

 

[kchap]

I took delivery of some other gear at the same time so I can't be sure. I would suggest you E-mail Apollon. I'm sure they would help you.

 

[mike70]

I took delivery of some other gear at the same time so I can't be sure. I would suggest you E-mail Apollon. I'm sure they would help you.

is what i have done ... but since some days ... no reply.

 

[sandeep_s300]

Finally it’s here . Topping d90 iii sabre dac with preamp Connected directly to Apollon ncx500 stereo power amp. Stealth audio hybrid mlt speaker cables , qed ref subwoofer rca , qed optical input , Tellurium Q silver diamond XLR, Shunyata Venom v12 NR Power cord , Speakers M&K sound s300 with X10 subwoofer.

 

[sandeep_s300]

Have noticed that when I turn on the amp, it adds back emi noise to my isotek Aquarius board, even though the amp is powered by shunyata theta NR power cable from Aquarius . EMI analyser reading goes up from 5-6 to 25-26

 

[Labjr]

Have noticed that when I turn on the amp, it adds back emi noise to my isotek Aquarius board, even though the amp is powered by shunyata theta NR power cable from Aquarius . EMI analyser reading goes up from 5-6 to 25-26

I guess the power cable isn't doing it's job.

 

[sandeep_s300]

I guess the power cable isn't doing it's job.

Not really or may be it’s not enough. I tested the cables for emi reduction capability and they do real good job . The NR cables are used from medical devices to audio visual and are proven cable that shunyata makes. I have a Sunfire 7ch 400w @ 4ohms per channel amp which doesn’t add back anything back to the power conditioner.
I have ordered a seperate surge protected emi reducer board made by brand called Thor. Will try seperate the amp onto it and see how it behaves .

 

[antcollinet]

Not really or may be it’s not enough. I tested the cables for emi reduction capability and they do real good job . The NR cables are used from medical devices to audio visual and are proven cable that shunyata makes. I have a Sunfire 7ch 400w @ 4ohms per channel amp which doesn’t add back anything back to the power conditioner.
I have ordered a seperate surge protected emi reducer board made by brand called Thor. Will try seperate the amp onto it and see how it behaves .

Power cables can't influence conduced interference - which is where most audible interference sits. Question is - does this measured interference result in anything audible. It is only poorly designed kit that passes EMI from the power port to anything on the audio side of the kit.

 

[sandeep_s300]

Power cables can't influence conduced interference - which is where most audible interference sits. Question is - does this measured interference result in anything audible. It is only poorly designed kit that passes EMI from the power port to anything on the audio side of the kit.

It does - it’s audible . Which is why I recently spent on a new shunyata theta NR that just got released after trying a used venom v12 NR cable . There is a power cable with active noise reducer , names, ifi supanova . That cable by itself adds noise that my noise analyser red light comes on - means it went beyond its measurement capabilities lol.

 

[antcollinet]

It does - it’s audible . Which is why I recently spent on a new shunyata theta NR that just got released after trying a used venom v12 NR cable . There is a power cable with active noise reducer , names, ifi supanova . That cable by itself adds noise that my noise analyser red light comes on - means it went beyond its measurement capabilities lol.

Are you sure it is the same noise that is audible. Most audible noise is conduced through ground loops - in which case a much better solution is balanced analogue interconnect, or galvanic isolation upstream of the analogue interconnect - rather than expensive and needless power conditioners that don't solve the ground noise in any case.

 

[Javierfr_arg]

Hello, everyone ! I want to ask you a question, I am from Argentina and I bought this excellent amplifier which I have connected to the pre out xlr output of a yamaha rxa6 whose output values according to yamaha are 2 to 4v and according to Audioholics 4 to 8v. My question is, should I use the amplifier gain at 29 dB or use the 20 dB gain and raise the level of the front speakers in the Yamaha level settings? Which one would work better? Thank you very much and sorry for the text errors! greetings to all !

 

[goryu]

Why don't you try it and find out?

 

[antcollinet]

Hello, everyone ! I want to ask you a question, I am from Argentina and I bought this excellent amplifier which I have connected to the pre out xlr output of a yamaha rxa6 whose output values according to yamaha are 2 to 4v and according to Audioholics 4 to 8v. My question is, should I use the amplifier gain at 29 dB or use the 20 dB gain and raise the level of the front speakers in the Yamaha level settings? Which one would work better? Thank you very much and sorry for the text errors! greetings to all !

I doubt very much that there will be any audible difference between the two options.