[Eugenio_Fen]

Some sellers are already selling the EVO STA SE stereo power amplifier, which I can't find on the official Nuprime website yet.
What's the current status? Is it in production or not, and when do you plan to officially release it?
 I can't wait to get it or try it out, since I already own the base model EVO STA.
What improvements does the SE model have?
Many thanks!

[mresseguie]

Not that I have an inside source, but the word I heard is that they will begin shipping on Feb 23rd. I'm looking forward to mine.   
Chinese New Year celebrations begin tomorrow, so I imagine everyone is taking a break.

[AllanS]

Jason may step in with a more complete description but he briefly lists changes incorporated into the EVO STA SE in this thread: https://www.audiocircle.com/index.php?topic=193240.msg2027925#msg2027925
- updated amp board (no details) and change to ANC GaN PS described here:
https://nuprimeaudio.com/product/ida-9/ https://nuprimeaudio.com/product/ida-9/
The link is to a different product and I assume different implementation but it’s reasonable to assume the characteristic improvements are the same.

[rustydoglim]

I just published the product page: https://nuprimeaudio.com/product/evolution-sta-se/
This is a beast!
The old review of Evolution STA serves as a reference: https://nuprimeaudio.com/nuprime-evolution-sta-stereo-power-amplifier/
The STA-SE upgrade is a huge improvement, not an incremental one.  Will it surpasses the 30,000 CH A1.5 this time?  I think so.

[mresseguie]

400 watts per channel combined with 40A ultra-high current and low resistance terminals. This will easily drive my low efficiency 2-way speakers.
 

Looking forward to this!

[mresseguie]

I received my EVO STA-SE a while back, but I got bogged down with 'things', so I only two hours ago unboxed my EVO STA-SE and hooked it up to my system via Kimber Kable Hero XLR cables. So...with precious little burn in, I notice it sounds very nice. Bass is more noticeable and tighter. Midrange....especially female voices is very nice and sweet.

I'm playing cello/piano/violin music now. So nice and clear with a touch of warmth.

I have not added my preamp yet. System right now is: EVO STA-SE + Holo Spring3 KTE + Fritz LS/5-R speakers (82.5dB).

I'll let it play all night and listen again in the morning.

[AllanS]

 

[mresseguie]

One thing I find very interesting is its power. The amp that it replaced is an IceEdge1200AS2 with 600w/ch into 8 Ohms. The EVO STA-SE is rated @ 400w/ch into 8 ohms - yet the EVO STA-SE seems to be more powerful. Why would that be the case, I wonder? I don't think I'm imagining it.

Vocals are clearer, more natural. Music is warmer, more natural sounding, too. The top of the amp gets mighty warm. It's been too long since I felt the top of my original EVO STA to remember if it gets equally hot or if this one runs hotter.

I've listened to multiple genre of music, and have not noticed any bad or bright sounds. I'll try some older Rock & Roll to hear if it sounds off or bright. Hopefully, I can add my Nuprime preamp tomorrow. I watched a couple hours of Netflix videos already, and everything sounds quite good. No complaints.

So far....this amp has done no harm - nothing negative to report. I'm looking forward to more listening tests.

[AllanS]

The first iteration of the main system ran IceEdge 1200AS1 based mono blocks.  There was definitely an effortlessness to these amps but I prefer the sound of the current 20 WPC Schiit Aegir over those and every higher powered amp since then playing through my Sapphire M4s. For my preferences and setup they just play well together.  The others sounded fine but nowhere near better enough to justify up to 10x difference in price.
I can understand dynamic headroom and linearity when comparing 1200W on tap to 20, but comparing 600 to 400 would seem to be inconsequential.  Maybe the SE is a better match for the Fritz impedance curve where it matters most to your ears?

[rustydoglim]

Power rating doesn't necessarily equal the ability to drive a speaker. 
Power = Current x Voltage.   Low efficiency speakers need more current to drive, and therefore two amps could be rated the same, but one with higher current is better at driving a low efficiency speaker. 
Audiophile companies typically rate the max power at 1% THD.  But other companies could use the 10% THD (typically used by home theater, car power amps, chips).

[Larsf333]

6 Weeks ago I sent my Evo sta to nuprime to get it upgraded to SE level.
Yesterday, I got it back. Right out of the box it plays very well, but as mresseguie also has reported, it runs quite hot.
The original Evo sta did not run hot.
The new manual states it has the same power consumption as the old model, 26W.
To check this out, I have now measured the power consumption in idle mode, and the meter says 80 Watts!
That is a pretty high consumption, and it explains why it runs hot.
This high usage was unexpected, and with the high energy prices it is an unexpected extra price to pay running the amplifier.
Nuprime should update the manual and specify the correct power usage, unless it is a fault in my amplifier.
So Please follow up on the power usage, and explain why.
Thank you.

[mresseguie]

I guess I am not surprised it draws more power given how warm it gets. However, I’m not complaining - quite the opposite. This amplifier sounds great in my system and I still haven’t added my preamp.

I am very happy with this new amplifier. I can’t wait to hear it powering my Daedalus Audio speakers (though it will be a few months before they arrive).

Excellent amplifier, Jason!

[rustydoglim]

6 Weeks ago I sent my Evo sta to nuprime to get it upgraded to SE level.
Yesterday, I got it back. Right out of the box it plays very well, but as mresseguie also has reported, it runs quite hot.
The original Evo sta did not run hot.
The new manual states it has the same power consumption as the old model, 26W.
To check this out, I have now measured the power consumption in idle mode, and the meter says 80 Watts!
That is a pretty high consumption, and it explains why it runs hot.
This high usage was unexpected, and with the high energy prices it is an unexpected extra price to pay running the amplifier.
Nuprime should update the manual and specify the correct power usage, unless it is a fault in my amplifier.
So Please follow up on the power usage, and explain why.
Thank you.

Please create a help desk ticket, take a photo of your idle mode power measurement. 

[Larsf333]

I also tried to measure the power consumption in stand by mode, and my power meter measured an unreasonable high value.

To make sure, that the measurement was correct, I therefore bought a new power meter.

Now, it measures stand by consumption of 1.1 W, and idle power consumption of 28.2W

That seems more reasonable, and is only slightly more than the specifications.

So there is no need to create a ticket for support.

But still, the amp gets hotter than the old version, a thermometer measures the surface temperature to be about 38 celsius.
But the amp plays very well, so I guess there is nothing to worry about.

[rustydoglim]

Your measurement seems correct, or within range.
Keep in mind that Evo STA-SE has nearly twice the power, therefore even at idle power, it will consume more than Evo STA.
Our GaN PSU was designed for audio performance, even though it consumes a lot less power that linear PS, consuming absolutely low power during idle is not its design goal.
Regarding the heat on the cover, we have this practice in all our products that we use the entire aluminum case as the heatsink (instead of letting heat traps inside!). The internal heatsinks conduct heat to the case.

Jason

[mresseguie]

Your measurement seems correct, or within range.
Keep in mind that Evo STA-SE has nearly twice the power, therefore even at idle power, it will consume more than Evo STA.
Our GaN PSU was designed for audio performance, even though it consumes a lot less power that linear PS, consuming absolutely low power during idle is not its design goal.
Regarding the heat on the cover, we have this practice in all our products that we use the entire aluminum case as the heatsink (instead of letting heat traps inside!). The internal heatsinks conduct heat to the case.

Jason

Jason,

As long as you're talking about heat dissipation on the top plate, I have a question:

<This may be my imagination> In the first couple weeks since I began using my EVO STA-SE, I felt the top right side was especially warm to the touch. However, the last couple of days it doesn't seem to be as hot as it used to be. Am I imagining this heat difference? Does it generate a bit less heat after a couple hundred hours of burn in? [I remember something similar a long time ago with my IDA-8.]

[Larsf333]

I agree with mresseguie.

When I connected my upgraded evo sta-se I also felt, that it became quite hot.

I have no exact measurements, but now after 10 days, it actually does not seem to be as hot as it was in the start?

[rustydoglim]

May be initially the amp was cold and the heat started from one area but over time as you keep using it, it evenly spread out?