BUCKEYEAMPS Hypex NCx500 Amplifier 2channel Review

[Sokel]

NAD would never do this. No company who gets their products UL or ETL certified would ever do this.

Nad's Purifi version with it's custom PSU hits about 30 more watt than the reference design with a tiny noise penalty:

 

[Apollon Audio]

Where did you read that Hypex said their 1200w supply is adequate to allow both of these modules to output their full rated power? Do you think Hypex puts current limiters in the amp modules for no reason? How is it possible to utilize this protection if the supply blows up before it can be triggered?

Even simple math says 700+700=1400w. The supply is rated for 1200w. And you ALWAYS want to overbuild the supply. Bottom line is the weak link needs to be the current limiters in the amp modules. Or you are offering a junk product to the marketplace. NAD would never do this. No company who gets their products UL or ETL certified would ever do this.

NAD has underpowered models as well. Look at the M28 - 7 channel. It uses the same power supply as the M23 - 2 channel.

 

[Apollon Audio]

Nad's Purifi version with it's custom PSU hits about 30 more watt than the reference design with a tiny noise penalty:

View attachment 304250 View attachment 304251

This is due to the higher DC voltage output from their custom power supply.

 

[Positivevibrations]

Once again, this is assumed by the designers. From the datasheet:
Output Power (SMPS1200A700) Connected amplifier: 2 x UcD700OEM , f = 1kHz, power sweep 0W up to Pmax. Distortion figures (THD+N) at the stated power ratings are at 1%. Parameter Conditions Symbol Unit Note Total amplifier output power at different input voltages. 240VAC Load = 4Ω Load = 8Ω Po 2x 620 2x 370 W 230VAC Load = 4Ω Load = 8Ω Po 2x 600 2x 340 W

They rate it as a 1200w supply for a reason. If it was designed to handle 1400w safely, they would call it a 1400w supply. But even 1400w isn’t enough. Because the amps are not 100% efficient. So like the reviewer said, a 1600w supply would be the way to go.

Me personally would use a 2000w supply minimum. Because I don't like to run the bag off of things. As a manufacturer you can’t assume every customer isn’t gonna test the limits of the amps. And if the customer does, you want the amp current limiters to gently trigger, and safely shut down the supplies without even a pop from the speakers. That’s the ideal way a proper amp handles an over current situation.

 

[Positivevibrations]

NAD has underpowered models as well. Look at the M28 - 7 channel. It uses the same power supply as the M23 - 2 channel.

Ya but you don’t know what kind of protection circuitry they implemented in their own custom supply. Or even if they lowered the voltage to reduce the power output.

 

[Sokel]

This is due to the higher DC voltage output from their custom power supply.

What's intresting about this review (NAD) is that the end of the graph seems to exceed the 1% mark by far!
(goes straight to -20db TDH+N! )

 

[Toni Mas]

They rate it as a 1200w supply for a reason. If it was designed to handle 1400w safely, they would call it a 1400w supply. But even 1400w isn’t enough. Because the amps are not 100% efficient. So like the reviewer said, a 1600w supply would be the way to go.

Me personally would use a 2000w supply minimum. Because I don't like to run the bag off of things. As a manufacturer you can’t assume every customer isn’t gonna test the limits of the amps. And if the customer does, you want the amp current limiters to gently trigger, and safely shut down the supplies without even a pop from the speakers. That’s the ideal way a proper amp handles an over current situation.

Audio amplifiers are not power sine wave generators... What for? Powering an electric oven?

 

[Sokel]

Audio amplifiers are not power sine wave generators... What for? Powering an electric oven?

Tell that to Genelec with it's 6KW per channel amplification of 8381A.

8381A SAM™ Adaptive Point Source Main Monitor - Genelec.com

Our 8381A empowers engineers and creators to perceive every sonic detail, offering true-to-life sound level and dynamics – with the full flexibility of free-standing monitor placement and advanced room adaption.

www.genelec.com

 

[Toni Mas]

Tell that to Genelec with it's 6KW per channel amplification of 8381A.

View attachment 304256

8381A SAM™ Adaptive Point Source Main Monitor - Genelec.com

Our 8381A empowers engineers and creators to perceive every sonic detail, offering true-to-life sound level and dynamics – with the full flexibility of free-standing monitor placement and advanced room adaption.

www.genelec.com

Question is: what's the point?

Or what's the use?

Do you need almost 130db SPL for a home hifi?

Will your loudspeakers admit that power?

 

[Apollon Audio]

Ya but you don’t know what kind of protection circuitry they implemented in their own custom supply. Or even if they lowered the voltage to reduce the power output.

I have played with the M28. Their custom power supply actually outputs higher DC voltage than the SMPS1200A400. This is why when testing only two channels you get more power out of the Purifi modules. When you load all 7 channels and push it hard, the limitations of the power supply start to show up fast. But this amplifier was intended to power small to medium surround system and not PA speakers or power hungry multi way speakers.

 

[Positivevibrations]

Audio amplifiers are not power sine wave generators... What for? Powering an electric oven?

I personally seen the overcurrent protection in a Purifi amp trigger with a pair of Magnepan 20.7’s. The amp just gently shut down without a pop or anything. And started back up without a hitch. But only because the supply was rated 300w more than the amps. That’s why it went smooth.

Soon I’m going to try the NCx500’s on the same speakers. But each module will have a dedicated supply of course. Or a stereo build with a 2000w supply from MicroAudio would work.

 

[Sokel]

Question is: what's the point?

As they say "true -to- life sound level and dynamics".

 

[Anthony LoFi]

We have a myriad of "experts" to discuss a failure.
The failure as yet does not have a proven cause.
We are speculating.
So why dont we end this thread and do a Part 2 when the assembler/manufacturer has had time to analyse the problem, simulate the fault conditions, in conjunction with the component manufacturer and determine the issue that caused the fault.
Buckeye have proven they honour any problems raised in the past and have sent the owner a replacement part.
Lets give them time to identify the problem and report back.

Then with more scientific verified information we may find further discussion is not needed.
I fear our OP has performed a test in the spirit of the ASR culture and now has all sorts of innuendos and disparaging remarks.
We are all here as a world wide community of interested enthusiasts to support each other and help "newbs" enter this new information age of how products work and perform.
Some comments I believe dont meet the basic requirement of being civil and form a constructive discussion.
For ASR to excel, we all have a part to play as forum members to treat others as we would expect to be treated.

 

[Toni Mas]

As they say "true -to- life sound level and dynamics".

Chamber music or Beyonce live ?

 

[Sokel]

Chamber music or Beyonce live ?

Have ever heard a single clarinet playing loud live?
Can easily hit 110db SLP.So... not far for truth if it truly achieves the stated 129db peaks.

 

[Positivevibrations]

We have a myriad of "experts" to discuss a failure.
The failure as yet does not have a proven cause.
We are speculating.
So why dont we end this thread and do a Part 2 when the assembler/manufacturer has had time to analyse the problem, simulate the fault conditions, in conjunction with the component manufacturer and determine the issue that caused the fault.
Buckeye have proven they honour any problems raised in the past and have sent the owner a replacement part.
Lets give them time to identify the problem and report back.

Then with more scientific verified information we may find further discussion is not needed.
I fear our OP has performed a test in the spirit of the ASR culture and now has all sorts of innuendos and disparaging remarks.
We are all here as a world wide community of interested enthusiasts to support each other and help "newbs" enter this new information age of how products work and perform.
Some comments I believe dont meet the basic requirement of being civil and form a constructive discussion.
For ASR to excel, we all have a part to play as forum members to treat others as we would expect to be treated.

It’s so blatantly obvious why the failure occurred. Any diagnostic measures are not required beyond reading the datasheets prior to the build. The only solution moving forward are the following 3 options:

1: Upgrade the amps to use dual SMPS1200A700’s
2: Use a higher current supply
3: At minimum put a disclaimer on the webstore where the amp is advertised, that must be acknowledged and a box checked that says the power supply may blow up if driven to full output. And then at least the client knows what they’re in for if they overdrive it.

 

[Rick Sykora]

Am cross posting this from another thread as seems appropriate to repeat here. I purchased a 2 channel Buckeye NCx500 (just like the one tested by the OP).

Here is a look at THD vs Power (at 1 kHz and a 4 ohm load)...

The blue trace is with both channels driven and the purple one is a single channel. For the single channel case, it does meet the Hypex spec, doing just over 700 watts at 1% THD. Driving both channels, you can see it is about 600 watts. Not sure why the OP was not able to replicate but worked just fine for me.

p.s. and sounds great too!

 

[pma]

Nice to see you learning .

 

[Positivevibrations]

Am cross posting this from another thread as seems appropriate to repeat here. I purchased a 2 channel Buckeye NCx500 (just like the one tested by the OP).

Here is a look at THD vs Power (at 1 kHz and a 4 ohm load)...
View attachment 304258

The blue trace is with both channels driven and the purple one is a single channel. For the single channel case, it does meet the Hypex spec, doing just over 700 watts at 1% THD. Driving both channels, you can see it is about 600 watts. Not sure why the OP was not able to replicate but worked just fine for me.

p.s. and sounds great too!

That poor supply was probably right on the verge of explosion. Try holding that power level for a few minutes.

 

[DS23MAN]

It’s so blatantly obvious why the failure occurred. Any diagnostic measures are not required beyond reading the datasheets prior to the build. The only solution moving forward are the following 3 options:

1: Upgrade the amps to use dual SMPS1200A700’s
2: Use a higher current supply
3: At minimum put a disclaimer on the webstore where the amp is advertised, that must be acknowledged and a box checked that says the power supply may blow up if driven to full output. And then at least the client knows what they’re in for if they overdrive it.

It's not blatently obvious. Hypex sell kits with 2 Nilay's with one smps500. Purify uses 2 modules with one smps1200. And these type of configurations are no problem because all Hypex smps have current protection build in. What is bloody obvious is that this smps was faulty from the start.