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BUCKEYEAMPS Hypex NCx500 Amplifier 2channel Review

Let's just say licensed electricians in the US are almost on par with doctors in pay rate/hour.
Not to demean licensed electricians, they are more than deserving of a good living wage
just like everyone here and it takes years to fully learn the craft. ;)

But compared to putting together a good stereo or multich Hi Fi, running a couple of
extra lines for outlets is easy-peasy. My god, it's only 3 wires, hot, neutral, and ground.
I did all the electrical work for my machine shop up in Chicago myself. Hardest part
was up there everything has to be run in metal conduit and it takes a bit to learn how to
use the pipe bender with inside and outside bend measurements.
Just don't forget to turn off the power before messing about. LOL
 
Not to demean licensed electricians, they are more than deserving of a good living wage
just like everyone here and it takes years to fully learn the craft. ;)

But compared to putting together a good stereo or multich Hi Fi, running a couple of
extra lines for outlets is easy-peasy. My god, it's only 3 wires, hot, neutral, and ground.
I did all the electrical work for my machine shop up in Chicago myself. Hardest part
was up there everything has to be run in metal conduit and it takes a bit to learn how to
use the pipe bender with inside and outside bend measurements.
Just don't forget to turn off the power before messing about. LOL
Our problem is where and how to run the lines inside the house even though it is usually just one covered Romex line. Code dictates fire breaks from garage to house and between floors, so you have to pull able to cut and patch drywall between floors/walls and the service panel in our garage to get through the fire walls (combination of 2"x4" horizontal "stoppers" and fireboard between studs), then deal with how and where to route the lines heading to finished basement, first, or second floor through the existing finished walls or ceilings. I am very thankful my electrician's apprenticeship decades ago was almost all new construction or industrial jobs -- much easier to run before everything is finished! Existing construction is a PITA, and drywall is not in my skill set.

When our basement was finished many years ago I tried to have them add a switch on the upper floor and they refused as getting through the fire breaks would've required major surgery and wall repairs. Last time I helped a friend with a similar situation, we ran conduit along the outside to reach his first-floor living room and add a 20-A line for his stereo. If I added a line now I'd probably sleaze my way out by running along baseboards instead of trying to get through walls.
 
Existing construction is a PITA, and drywall is not in my skill set.
OMG, existing construction is the worst!
My 1910s-early 1920 built house up in Chicago was double row brick on the outside and lathe & plaster walls inside..
Even the basement had a lathe & plaster ceiling though it was otherwise never finished???
Each room had only 1 115 outlet except for the living room which had 2. :facepalm:
And an awesome 60amp service box.
I could write a book on the electrical work I did there over the next 32 years.
Then there was the plumbing -------------------:eek:
Back on topic, sorry folks.
 
This beast can run on 120V, but even on 240 your outlet will be struggling:


No it wiil not struggle at all. As mentioned earlier, music reproduction usually draws less an 1/8 of the required power. Testing may warm up some dummy loads, but playing music is not a major strain for these power supplies. Although a 3000 watt rating would seemingly exceed a single AC service, the supply is only rated for 1000 watts continuous with a 4 ohm load.

Still considerably less than my wife’s hairdryer!
 
This is a GREAT amp at a very reasonable cost.
I'd hate to see some of the babbling and other mis-statements here
give this amp a negative impression to folks ending up here after a google search..
IMHO, Highly Recommended.
Sal1950
 
No it wiil not struggle at all. As mentioned earlier, music reproduction usually draws less an 1/8 of the required power. Testing may warm up some dummy loads, but playing music is not a major strain for these power supplies. Although a 3000 watt rating would seemingly exceed a single AC service, the supply is only rated for 1000 watts continuous with a 4 ohm load.

Still considerably less than my wife’s hairdryer!

You're wife's hairdryer has forced high velocity air cooling and this power supply would need that as well. The idle losses and efficiency means it will need a sizable heatsink even operating at low powers, letalone high.
 
You're wife's hairdryer has forced high velocity air cooling and this power supply would need that as well. The idle losses and efficiency means it will need a sizable heatsink even operating at low powers, letalone high.

According to the Hypex data sheet, the 1000 watts continuous is free air cooling. Please note, I did not say, the supply was not going get warm or need heatsinks in real world app.

I do not have this supply or any amp capable of such high output. Given this, have never seen the lights dim while using my audio system. I cannot say the same for when my wife is drying her hair!;)
 
According to the Hypex data sheet, the 1000 watts continuous is free air cooling.

1691879762318.png


If you believe you can succesfully disipate ~75W on a continuous basis at 1kW in free air with just a L shaped flat ~3mm plate of (250x145mm) aluminum, I've got a few bridges to sell you.

The simple facts are the supply needs forced air cooling even at 1kW. Put it inside a case of any type and you will rapidly exceed the ambient maximum operating temperature rating of the entire SMPS module which is 50 degrees C. Add whatever amplifiers you are powering with this supply and the internal temperatures will quickly exceed what is reasonable for reliable, long term operation.

There's way too many assemblers screwing these amplifiers and supplies into casework with little to no consideration of thermal management.
 
View attachment 305437

If you believe you can succesfully disipate ~75W on a continuous basis at 1kW in free air with just a L shaped flat ~3mm plate of (250x145mm) aluminum, I've got a few bridges to sell you.

See the Hypex datasheet. Seems to imply a heatsink but cannot say the conditions are fully stated so feel free to critique further. No dog in this fight so thanks for sharing your knowledge.

Do Aussies build good bridges?;)
 
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Seems to imply a heatsink but cannot say the conditions are fully stated so feel free to critique further.

They say this:

1691890320640.png


And this:
1691890555466.png


The implication being 1000W continuous would raise the heatsink temperature to 95 degrees C in free air. Anything more than that, will raise the temp over the thermal shutdown threshold. At 1000W, there is ~75 watts of heat going into that heatspreader in free air. 'Continuous' must be actually very short- like a minute maybe.

Even if you could keep the heatspreader under 95 degrees C, with a large heatsink the ambient air inside casework will rise above the 50 degree max operational limit. That affects all the components not thermally attached to that spreader. Ones that produce heat themselves. As the air heats up, their ability to shed heat into an already heated ambient environment is severely diminished. This is where forced air cooling comes in. Even a small fan will move the heated air out and allow the module to operate within its ratings.

Do you have a FLIR type IR imager? They are probably the most useful tool I've bought in the last few years. And a macro lens for it. Changes your life when fault finding electronics. You can look at a power amplifier with 50 output devices and see any that are dead (they are cooler). You can spot amplifiers with one channel low in bias or too high before you even touch it. You can see failed opamps, transistors, resistors etc. Caps in SMPSs running too hot due to elevated ESR.

It's often single components that reach astronomical temperatures, way outside their operational maximums. I had a strange phenomenon where a digital filter IC was glitching wildly after 4 or 5 minutes and it wasn't even running warm. I tracked the problem to a corrupted data stream. Taking the lid off provided just enough ambient air for the problem to not occur. But why? It was a nearby 7808 voltage regulator in free air/no heatsink on the PCB. It was running about 80-90 degrees C and although it was fine, the nearby optocoupler (isolating digital feed to the FIR OS IC) didn't like being heated to around 55-60 degrees C. When hot, the optocoupler sent the glitches which made their way right through to the audio after the D/A conversion. Remotely mounted the 3 term regulator to the chassis, replaced the optocoupler and fixed the problem. A heatsink on the regulator wouldn't have helped as the ambient temperature would have still been elevated (sealed casework). The problem would have occurred after perhaps 20 minutes instead of 5.
 
One sneaky caveat of many modules (not just these) is a spec stating no heat sink required in free air. The problem is that most of us put our stuff in cases... For high-current (but low-voltage) SMPS regulators in my former life a not uncommon failure mechanism was the switching inductor would overheat and fail. The manufacturer would typically spec a very low Rdc inductor, customers would substitute a cheaper one with higher resistance, and Bad Things happened. For class D amplifiers, the output filter inductor can also be problematic, along with the shunt output filter capacitor (that must absorb HF pulses that essentially look like very high ripple current to the cap).

As for Australian bridges, well, I had a vague memory from my ancient college course that discussed bridge failures, and found this with a search (West Gate Bridge collapse, Melbourne):
791a7d67386d7bab5eede631c692d17a


Here (USA), the Tacoma Narrows bridge was one we studied in classes civil and EE as an example of resonances leading to undesirable consequences:
iu


And of course, as a design engineer, some of my most successful oscillator designs began life as amplifier designs. ;)

Haven't had any such electrical or mechanical oscillation problems with my Buckeye Amps, fortunately.
 
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As for Australian bridges, well, I had a vague memory from my ancient college course that discussed bridge failures, and found this with a search (West Gate Bridge collapse, Sydney):
One of the most famous bridge failures was the Ponte Morandi in Italy 2018, which will have its 5 year anavarsery tomorrow. Sadly 43 people lost their lives when the bridge collapsed during a rain storm.
By Michele Ferraris - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=71779981
 
West Gate Bridge collapse, Sydney

The West Gate Bridge collapse was actually in Melbourne in 1970. As a young boy, I remember my Dad driving us along the road to the bridge, where you could walk/drive along the partially completed section and get quite close to the broken off part. It sat like that for about 2 years and was quite a sight up close. There had been barriers, but curious people had removed them and the braver ones drove their cars quite a distance to get closer.
 
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One sneaky caveat of many modules (not just these) is a spec stating no heat sink required in free air. The problem is that most of us put our stuff in cases... For high-current (but low-voltage) SMPS regulators in my former life a not uncommon failure mechanism was the switching inductor would overheat and fail. The manufacturer would typically spec a very low Rdc inductor, customers would substitute a cheaper one with higher resistance, and Bad Things happened. For class D amplifiers, the output filter inductor can also be problematic, along with the shunt output filter capacitor (that must absorb HF pulses that essentially look like very high ripple current to the cap).

As for Australian bridges, well, I had a vague memory from my ancient college course that discussed bridge failures, and found this with a search (West Gate Bridge collapse, Sydney):
791a7d67386d7bab5eede631c692d17a


Here (USA), the Tacoma Narrows bridge was one we studied in classes civil and EE as an example of resonances leading to undesirable consequences:
iu


And of course, as a design engineer, some of my most successful oscillator designs began life as amplifier designs. ;)

Haven't had any such electrical or mechanical oscillation problems with my Buckeye Amps, fortunately.
Regarding measuring conditions some state exactly what they use so it was easy for me too to choose a case with similar Rth (it's rather big but matches the module).


Rht.PNG


What I find -how can I say it- beautified,is the scale that they use in graphs like efficiency and dissipated power which make it seem better than it is,specially efficiency which is low in low power.
eff.PNG eff2.PNG
 
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Regarding measuring conditions some state exactly what they use so it was easy for me too to choose a case with similar Rth (it's rather big but matches the module).


View attachment 305501

What I find -how can I say it- beautified,is the scale that they use in graphs like efficiency and dissipated power which make it seem better than it is,specially efficiency which is low in low power.
View attachment 305502 View attachment 305505
Ha! Yeah, there is absolutely no reason for the X-axis to extent to 1200 W
 
Ha! Yeah, there is absolutely no reason for the X-axis to extent to 1200 W
Yep,at least for the two channel measurement who never reaches that.
If used as mono is it's rated (90 seconds only) power burst.
 
They say this:

View attachment 305467

And this:
View attachment 305468

The implication being 1000W continuous would raise the heatsink temperature to 95 degrees C in free air. Anything more than that, will raise the temp over the thermal shutdown threshold. At 1000W, there is ~75 watts of heat going into that heatspreader in free air. 'Continuous' must be actually very short- like a minute maybe.

Even if you could keep the heatspreader under 95 degrees C, with a large heatsink the ambient air inside casework will rise above the 50 degree max operational limit. That affects all the components not thermally attached to that spreader. Ones that produce heat themselves. As the air heats up, their ability to shed heat into an already heated ambient environment is severely diminished. This is where forced air cooling comes in. Even a small fan will move the heated air out and allow the module to operate within its ratings.

Have experienced this empirically as have done both liquid cooling and air cooling for my dummy loads. Still can do liquid but a spare notebook cooler with dual USB fans is really convenient my limited purposes.

Do you have a FLIR type IR imager? They are probably the most useful tool I've bought in the last few years. And a macro lens for it. Changes your life when fault finding electronics. You can look at a power amplifier with 50 output devices and see any that are dead (they are cooler). You can spot amplifiers with one channel low in bias or too high before you even touch it. You can see failed opamps, transistors, resistors etc. Caps in SMPSs running too hot due to elevated ESR.

It is on my wish list. With how fancy cell phone cameras are, was hoping that maybe IR would eventually get offered. Which do you recommend? I think it would be a great tool for someone like Dylan. Most notably to ensure multichannel amps are getting sufficient cooling.
 
It is on my wish list. With how fancy cell phone cameras are, was hoping that maybe IR would eventually get offered. Which do you recommend? I think it would be a great tool for someone like Dylan. Most notably to ensure multichannel amps are getting sufficient cooling.

FLIR used to be the only ones to get.

My first unit was a FLIR, and lasted four years. But the latest unit I bought is a UNI-T UTi-260B. Over twice the IR resolution (49,152 pixels) and much nicer to use. USB streaming/live control, onboard micro SD, inbuilt Li-Ion battery I have never been able to run flat and is drop-proof and IP65 protected.

Tripod mount and cool (free) capture software. The macro lens is very useful if you want to look at individual SMD components on a PCB (yes, it's that good for that). It costs about $40 extra.


Macro lens:

Occasionally it glitches with image lag, but that's only when you move the device quickly after taking a lot of shots and I think that's to do with writing to the SD/buffering. It has both IR and visible light cameras and a mix function, but I rarely use the visible light camera as the distance to 'mix' the two images seamlessly is too close for what I do with PCB work. The visible/IR mix is fine for things like switch panels and house wiring (>0.3M).
 
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Regarding measuring conditions some state exactly what they use so it was easy for me too to choose a case with similar Rth (it's rather big but matches the module).


View attachment 305501

1691940172343.jpeg


I presume the 100mm means that the heatsink is 300x100mm. That’s a pretty big heatsink.
 
Regarding measuring conditions some state exactly what they use so it was easy for me too to choose a case with similar Rth (it's rather big but matches the module).


View attachment 305501

What I find -how can I say it- beautified,is the scale that they use in graphs like efficiency and dissipated power which make it seem better than it is,specially efficiency which is low in low power.
View attachment 305502 View attachment 305505
Right, it is not that they are not clear, but rather that "casual" users might not understand what "free air" means.
 
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