Help with Decision: Purifi, Nilai, NC502MP or ?

[ambd]

Hi really nice and honest review.
I am also trying getting used to the same amp, i guess the packaging is as it is, but seems to be stable enough.

We also seem to have a similar setup, though i do have the miniDSP flex balanced (4V output). So i only use the 20.5dB gain setting.
This info below is what i took from another thread here.

12.8dB = 11.5Vrms
20,5dB = 4Vrms
27,5dB = 2,4Vrms
29dB = 2Vrms

Regarding your pros I probably couldn´t have said it better myself. It´s definitely a solid amp plus there is no noise coming out of the speakers at all, even if I get real close.

But regarding the cons, even though i don´t know what the weak link in my chain is, my room, my speakers, the Wiim Streamer or my own preference?
It kind of sounds (exaggerated a bit) like the instruments are being played in a sound chamber or a black hole.
Plus there is some area - not sure what frequency range, that sounds kind of mushy. I do have some room modes though, in the area between 80 and 275Hz but these didn´t just appear with the new amp, so ...

I mean i bought the amp to have something different, something smaller, more efficient, more powerfull, less noise, an improvement overall... and i do get all these improvements. But the musical satisfaction just isn´t at 100%. So i might experiment with another pre-amp as well, might be difficult to find something suitable as i am not a big fan of ending up with four devices in my chain. streamer, pre-amp, dsp and amp. It just get´s too complicated for everyone else to use.

Hi, I am happy that the review helped you somehow. I have news about my experience with the Apollon that may help you further. I was about to send the Apollon back when I decided to make a last test. So, before packing the amplifier. I decided to reset my whole speaker position to zero and turn off the subwoofer and reposition the speakers from zero.

I followed the Sumiko method with Jennifer Warnes ¨Ballad of the Runaway Horse¨, as I have done several times. You can follow the steps here - https://www.thesoundapprentice.com/2019/11/sumiko-speaker-placement-guide.html

And after spending almost 3 hours, I was like wow, what a difference. Surely, some of that harsh edge is still there, but the center image is solid like a brick, and more importantly the midrange is not recessed anymore, it is very present. Due to the midrange being more present, in comparison to the extremes of the frequency spectrum, the harshness is not that easy to perceive. It is incredible how much change pays to properly position the speakers.

Surely, there is still much to improve to give a more 3d character to the center image and to smooth out a bit more those high frequencies, but having a solid center midrange at the right level is a very good starting point for an amplifier, like the Apollon, that does many amazing things.

So, after that and still trying to get to the sound I like, I got an Aiyima T8 tube preamplifier, and I inserted in the chain right after the Mini DSP Flex, so one pair of RCAs, for the main speakers with high pass filter and a bit of PEQ go from Mini DSP Flex to Aiyima and then to the Apollon and to the speakers. And a second pair of RCA goes from Mini DSP Flex directly to subwoofer.

With the Aiyima in, even with the stock tube, the harshness was a bit gone. But the sound became a bit muddy, the frequency extremes loss a bit in dbs, and the soundstage lost its accuracy. So, I got an NOS tube, the Western Electric 396A tube, I placed it in the tiny Aiyima T8 and the improvement in sound was nothing short of dramatic, all in all very positive. I still lost significant focus in imaging, mainly in instrument separation and soundstage accuracy, but the sound became very pleasant. I also lost some dbs from 12Khz up, but I gain some dbs in the bass region although probably the bass became a bit loser. The soundstage did not shrink horizontally, just lost some focus, but it gain a lot of depth. I am amazed by this tube.

The midrange, with that tube in, was the best I have been able to extract from the Apollon NCx500 and that may be enough to close the deal. I listened to some of my classic jazz favorites, (Hawkins, Webster, Quebec, Peterson, etc) and it was very a pleasant and long session. Long is important because I did not develop any sound fatigue.

Now, that I am starting to see the real sound of this amplifier, I think it really needs a good tube preamplifier that does not color a lot the sound, just softens the edges, gives presence, and leans a bit on the side of neutral (as opposed as super warm). I am still considering what would be a clear better option than the Aiyima T8. The Schiit Freeya name is everywhere but I am not sure that is going to be much better.

 

[dom_st]

I followed the Sumiko method with Jennifer Warnes ¨Ballad of the Runaway Horse¨, as I have done several times. You can follow the steps here - https://www.thesoundapprentice.com/2019/11/sumiko-speaker-placement-guide.html

And after spending almost 3 hours, I was like wow, what a difference. Surely, some of that harsh edge is still there, but the center image is solid like a brick, and more importantly the midrange is not recessed anymore, it is very present. Due to the midrange being more present, in comparison to the extremes of the frequency spectrum, the harshness is not that easy to perceive. It is incredible how much change pays to properly position the speakers.

interesting approach, thanks for sharing, will see where i end up with my speakers sounding the best, hopefully not in another room :-D
Glad you´re happy with your setup now!

 

[ambd]

interesting approach, thanks for sharing, will see where i end up with my speakers sounding the best, hopefully not in another room :-D
Glad you´re happy with your setup now!

I read another post in this forum where somebody chose the Purifi over the NCx500 in their system. I have not listened to a Purifi amplifier in my system but I have exchanged emails with many of the companies that build these amplifiers and many of them say that the difference between Purifi and Hypex NCx500 is so small that most people will have a hard time even noticing it. Furthermore, as much as some people that listened to both (Purifi and Hypex) in their systems preferred Purifi, others preferred Hypex NCx500. And this would be the same if we add to the mix some GAN based amps like the Starkrimson from Orchard Audio, some people prefer this amplifier and others do not.

Just in case it helps you, there is a tour or the Starkrimson where you keep the amplifier for a week and you only pay the shipping to the next person in the tour, all in exchange for an honest review at another forum. It is an interesting option, just google ¨Orchard Audio Starkrimson Stereo Ultra Amp Tour¨.

From what I have read in many forums, whatever you and I have been experiencing in our system regarding that sort of harsh sound and, somehow, the lack of a full body sound, with the NCx500, is a common experience among users of amplifiers with all these modules.

And yes, I know it is too much to have two preamplifiers in the mix. I agree with that.

I am not fully happy with the NCx500, even after repositioning the speakers. But, having said that, I felt so bad when I noticed the midrange disappeared that when it got back, it was a huge positive change. I come from tubes. I used to have a Conrad Johnson MV50, a 300B SET amplifier, a 45 SET amplifier, etc, so I like that sound. But I believe in Class D and I am sure that with the right tube preamplifier the NCx500 will sound amazing.

As I mentioned, with that WE396A tube in the Aiyima pre, the soundstage is much more 3D than without the Aiyima in the chain. At some point, I was considering the VTV Purifi or NCx500 amplifiers with a tube module already included. But, and this a huge but and the reason why I did not like it - what would happen if you cannot live with the sound that that particular tube stage is adding to the mix? to remove it properly it will not be as easy as just unplugging it. And different tubes have different sounds, so there is that risk always. And, on the other side, what if you change your speakers, and your new speakers have a warm and sort of dark sound? in that case, I would prefer to have the NCx500 as it is now, without any tubes. So, tubes there, inside the amplifier, did not make much sense to me.

All in all, I could still return the Apollon, but I would lose $300 because I have to pay shipping back (around $135), the refund will not include the shipping to me ($95) and the refund will deduct also 3% from total price ($40) due to credit card fees. But, even if I send it back, and then I get a Purifi, or a Nilai, the issue I have with the sound now will most likely remain the same. I am sure that there will be nuances between the sound of these different modules, but the issue with the sound I have now will probably be present with all of them. And there is always the possibility of, being totally subjective and thanks to our inability to remember correctly differences in sound (among other biases), that after I listen to the Purifi I may decide that the NCx500 sounded better! And that would be a disaster in every sense. So, I thought that it is better to work on fixing the issue with the harsh sound I have now, instead of changing amplifiers. Also, I truly believe that the portray of instruments of the NCx500, and the soundstage it presents is amazing.

I had a long exchange with the amazing people of Apollon, and they told me that in order to address the issue (I described it to them) I should change, ¨upgrade¨, the op amps. I am quoting from our exchange:

¨I would strongly recommend the Sonic Imagery 994 op amps for a more musical class A character or Sparkos SS2590 for a warmer tube like character. Sonic Imagery measures the best with this amplifier, even better than with standard OPA1656 . By musical, I mean that the music just sounds more dynamic and impactful. The sound is more 3D and you get better soundstage. The highs are smoother and richer sounding, it seems like you get more detail.¨

According to many online reviews, the Sonic Imagery 994 increases the level of detail to a very high standard, as if you were a professional recording engineer or producer that needs to hear every single detail on your mix. I do not think I need that. The Sparkos SS2590, on the other side, according to Sparkos, is an improved version of the Sparkos SS3602 and provides a warmer sound without losing much detail. So, I think I will buy the SS2590 and test them in the Apollon.

According to Apollon in the same exchange, the difference in sound (in the Apollon amplifiers) when using discrete op amps, such as those mentioned above, (and not with IC op amps) is measurable and also easy to spot when listening.

 

[pogo]

Try a T+A A200 (purifi) with switchable DF:
'A high damping factor tends to produce a more clearly defined, very precise and analytical sound image, whereas a reduced damping factor produces a more warm and softer sound image.' <- extract from the manual

 

[Rover]

I read another post in this forum where somebody chose the Purifi over the NCx500 in their system. I have not listened to a Purifi amplifier in my system but I have exchanged emails with many of the companies that build these amplifiers and many of them say that the difference between Purifi and Hypex NCx500 is so small that most people will have a hard time even noticing it. Furthermore, as much as some people that listened to both (Purifi and Hypex) in their systems preferred Purifi, others preferred Hypex NCx500. And this would be the same if we add to the mix some GAN based amps like the Starkrimson from Orchard Audio, some people prefer this amplifier and others do not.

Just in case it helps you, there is a tour or the Starkrimson where you keep the amplifier for a week and you only pay the shipping to the next person in the tour, all in exchange for an honest review at another forum. It is an interesting option, just google ¨Orchard Audio Starkrimson Stereo Ultra Amp Tour¨.

From what I have read in many forums, whatever you and I have been experiencing in our system regarding that sort of harsh sound and, somehow, the lack of a full body sound, with the NCx500, is a common experience among users of amplifiers with all these modules.

And yes, I know it is too much to have two preamplifiers in the mix. I agree with that.

I am not fully happy with the NCx500, even after repositioning the speakers. But, having said that, I felt so bad when I noticed the midrange disappeared that when it got back, it was a huge positive change. I come from tubes. I used to have a Conrad Johnson MV50, a 300B SET amplifier, a 45 SET amplifier, etc, so I like that sound. But I believe in Class D and I am sure that with the right tube preamplifier the NCx500 will sound amazing.

As I mentioned, with that WE396A tube in the Aiyima pre, the soundstage is much more 3D than without the Aiyima in the chain. At some point, I was considering the VTV Purifi or NCx500 amplifiers with a tube module already included. But, and this a huge but and the reason why I did not like it - what would happen if you cannot live with the sound that that particular tube stage is adding to the mix? to remove it properly it will not be as easy as just unplugging it. And different tubes have different sounds, so there is that risk always. And, on the other side, what if you change your speakers, and your new speakers have a warm and sort of dark sound? in that case, I would prefer to have the NCx500 as it is now, without any tubes. So, tubes there, inside the amplifier, did not make much sense to me.

All in all, I could still return the Apollon, but I would lose $300 because I have to pay shipping back (around $135), the refund will not include the shipping to me ($95) and the refund will deduct also 3% from total price ($40) due to credit card fees. But, even if I send it back, and then I get a Purifi, or a Nilai, the issue I have with the sound now will most likely remain the same. I am sure that there will be nuances between the sound of these different modules, but the issue with the sound I have now will probably be present with all of them. And there is always the possibility of, being totally subjective and thanks to our inability to remember correctly differences in sound (among other biases), that after I listen to the Purifi I may decide that the NCx500 sounded better! And that would be a disaster in every sense. So, I thought that it is better to work on fixing the issue with the harsh sound I have now, instead of changing amplifiers. Also, I truly believe that the portray of instruments of the NCx500, and the soundstage it presents is amazing.

I had a long exchange with the amazing people of Apollon, and they told me that in order to address the issue (I described it to them) I should change, ¨upgrade¨, the op amps. I am quoting from our exchange:

¨I would strongly recommend the Sonic Imagery 994 op amps for a more musical class A character or Sparkos SS2590 for a warmer tube like character. Sonic Imagery measures the best with this amplifier, even better than with standard OPA1656 . By musical, I mean that the music just sounds more dynamic and impactful. The sound is more 3D and you get better soundstage. The highs are smoother and richer sounding, it seems like you get more detail.¨

According to many online reviews, the Sonic Imagery 994 increases the level of detail to a very high standard, as if you were a professional recording engineer or producer that needs to hear every single detail on your mix. I do not think I need that. The Sparkos SS2590, on the other side, according to Sparkos, is an improved version of the Sparkos SS3602 and provides a warmer sound without losing much detail. So, I think I will buy the SS2590 and test them in the Apollon.

According to Apollon in the same exchange, the difference in sound (in the Apollon amplifiers) when using discrete op amps, such as those mentioned above, (and not with IC op amps) is measurable and also easy to spot when listening.

Greetings.
We replaced the buffer with another type of OPA 1656 or Sparco SS3602 .
What is the result?Are you satisfied with the NCx500 now?

 

[ambd]

Greetings.
We replaced the buffer with another type of OPA 1656 or Sparco SS3602 .
What is the result?Are you satisfied with the NCx500 now?

Hi!

What follows is purely subjective to my personal experience with this amplifier in my system and in my room.

The Apollon NCx500 has around 100 hours of use and I feel that it has become a bit smoother. In few words, its sound is a bit more full body and less harsh. This is hard to quantify and I could be biased in how dramatic is this change, but in my experience, this change is noticeable.

My regular speaker cables are Duelund DCA16GA, they have a particular sound that I can easily spot in a blind test against my two other speaker cables (a regular OFC 16ga from Crutchfield, and a Duelund DCA12GA 600V). I changed the Duelund DCA16GA which produces a very wide soundstage and clear imaging and it is a bit lean in the mid bass, for the Duelund DCA12GA 600V that produces a less wide soundstage and less define images but has a more pronounced mid bass.

As a consequence of all that, the sound became much less fatiguing. If I want an analytical sound I go for the Duelund DCA16GA, if I want less clear images but more musical and warm sound, I go for the Duelund DCA12GA 600V.

I was already happy there and clearly decided to keep this amplifier, as I am sure I would have to spend much more to get this sort of performance from any amplifier.

Two days ago, I received a pair of dual Sonic Imagery 994. I have been listening, on and off, for the last couple of days, with both speaker cables.

In general, with the Sonic Imagery op amps, this amplifier is in another level of low detail retrieval. With the new op amps in place, the soundstage became a bit wider (easy to notice for me at least), the midrange became a bit more airy as it lost a bit (just a bit) of mid bass energy. The most dramatic change with the Sonic Imagery op amps was the low detail retrieval. There are many songs where I am discovering sounds that I did not know were there before because I never was able to spot them. Unfortunately, this new level of low detail retrieval could be bad for bad recordings if the sound of the system due to the whole combination of elements is too bright. But, having said that, if you manage to balance this super low detail retrieval with another component in the system that smoothens a bit the sound, then it is a winning combination.

The sound is so good now that I am wondering if I really need a tube preamplifier in the mix.

Audio is the journey of tiny wins or improvements, and yes, some of those wins or improvements are relevant only to your own experience listening. So, I am still wondering if a tube preamplifier would make the sound a bit more holographic. I could easily test that hypothesis ordering the Aiyima T8 tube preamplifier that I returned and see how it goes. The Aiyima made the sound of the Apollon (with the stock op amps) lose a lot in the imaging department. But, now with the extra detail of the Sonic Imagerys, the Aiyima T8 with a Western Electric W396A tube may be the perfect balance.

I am also very curious about the Sparkos SS2590, and I may order them in the next months and see what they bring.

All in all, I believe that the subjective side of the audio journey, meaning the personal experience, is what makes it a real hobby, and allow that journey to be a quest, a search for, rather than a direct line to the best sound you can ever get...