BUCKEYEAMPS Hypex NCx500 Amplifier 2channel Review

[Rick Sykora]

Doesn't the original supplier (Hypex) cover the cost of failed units?

No, only if they determine the module was defective.

I believe they sell the same unit in their diy shop,wouldn't they cover it for me if it failed?

not sure, as have not bought or sold from diyclassd.com

So,it only comes down to shipping cost.

shipping is often a large portion of the cost, but could be more (notably relative to the module cost).

 

[Sokel]

No, only if they determine the module was defective.

As @Buckeye Amps said in an earlier post that's probably the reason of failure:

BUCKEYEAMPS Hypex NCx500 Amplifier 2channel Review

Its intended use is 700w. Whether it drives PA speakers or your home computer speakers is completely irrelevant. I’m not sure what your point is. I can’t imagine anything being so black and white as this situation. 700W? If this is your point you are the typical rma generator! And you should...

www.audiosciencereview.com

I believe they must have more clues than us all as they must have some internal communication with the owner/reviewer and I have no reason to doubt any of them three.

 

[peng]

Perhaps, but suggest he found good middle ground in this case. Unless it is clear the tester is credible and is not intending to do destructive testing, could simply have denied warranty coverage.

Agree on replacing the entire amp versus just the supply. However, like comparable audio vendors, he runs a lean shop and diagnosing means either shipping modules back to the supplier or to a repair shop. Doing this very often either translates into higher prices or potentially going out of business.

Agreed on the lean shop consideration. I bought my NC500MP (you suggested it as an good alternative to the Purifi equivalent at the time) from him, knowing full well the advertized 350/500 W 8/4 ohms was not a continuous (literally) rating. At that low price point, I am very happy with the amp and I know if I want a continuously rated 350/500w amp I would have to pay at least 2X or 3X, and would have been for no reasons because I use my amp for music listening, not test tone listening, let alone "continuous". I don't know why people would think amps need to be rated "continuous" and want it to mean continuous indefinitely. It would be an impressive spec though.

Perhaps buckeye should rate his 300/500 W 8/4 ohm amp a) 180/300 W 8/4 ohms, phase angle <=60 deg 20-20,000 Hz "continuous (indefinitely)",1% THD, 25 deg C ambient, 6 inches clearances on all sides, relative humidity 50% and also provide the more useful spec such as b) 250/400W, 1 kHz, 0.1%THD, ambient temperature 25 deg C average, for use with typical music contents. There are many ways, hard to satisfy everyone. I would definitely prefer an amp that provide the spec for music program use instead of the spec based on continuous indefinitely, then there is a better chance I have the info to choose based on my need.

 

[peng]

I think everybody agrees on that,

I doubt it, I, for one, do not agree on that. If I need to get a power amp, I would want to have as detail spec as possible, not something like 180W 8ohms, 300 W 4 ohms continuous, indefinitely. So I would prefer the spec to read 300 W 8 ohms, 500 W 4 ohms for typical music contents and 150 W/250W continuous indefinitely. Hard to please everyone!

 

[PeteL]

I doubt it, I, for one, do not agree on that. If I need to get a power amp, I would want to have as detail spec as possible, not something like 180W 8ohms, 300 W 4 ohms continuous, indefinitely. So I would prefer the spec to read 300 W 8 ohms, 500 W 4 ohms for typical music contents and 150 W/250W continuous indefinitely. Hard to please everyone!

Well, I agree with you, but you did not say you disagree of the definition of continuous, which was my point, not everybody agree on how amp should be specced, which was also my point.

 

[Rick Sykora]

As @Buckeye Amps said in an earlier post that's probably the reason of failure:

BUCKEYEAMPS Hypex NCx500 Amplifier 2channel Review

Its intended use is 700w. Whether it drives PA speakers or your home computer speakers is completely irrelevant. I’m not sure what your point is. I can’t imagine anything being so black and white as this situation. 700W? If this is your point you are the typical rma generator! And you should...

www.audiosciencereview.com

I believe they must have more clues than us all as they must have some internal communication with the owner/reviewer and I have no reason to doubt any of them three.

Very sure Buckeye’s call was a commercial one as he is savvy and is customer responsive. I will check with him on the technical aspects, but know he would send to Hypex for repair. As part of repair, Hypex would diagnose it.

 

[Buckeye Amps]

As @Buckeye Amps said in an earlier post that's probably the reason of failure:

BUCKEYEAMPS Hypex NCx500 Amplifier 2channel Review

Its intended use is 700w. Whether it drives PA speakers or your home computer speakers is completely irrelevant. I’m not sure what your point is. I can’t imagine anything being so black and white as this situation. 700W? If this is your point you are the typical rma generator! And you should...

www.audiosciencereview.com

I believe they must have more clues than us all as they must have some internal communication with the owner/reviewer and I have no reason to doubt any of them three.

Very detailed photos were sent of both the NCx modules and the SMPS and the owner + reviewer both noted swelling of one or more capacitors and the smell of burnt plastic. This, along with the behavior of the SMPS continuously clicking (endless cycle), it was easy to determine the SMPS failed. If it was the NCx modules, the MCU of our buffer board would have reported a fault via Red LED on the front.

Regarding sending out replacement parts vs. whole replacement amps: I leave this to the discretion of each customer. Whenever an issue is reported, I always offer a return/replacement procedure OR ask the customer if they are comfortable enough replacing a the defective part on their own. One of the benefits of a more modular build system.

 

[Worth Davis]

Just wanted to throw Buckeyeamps a cookie, I have 3 amps and everything has been fast, personal, and professional with tech and discussions. I’m sure this will be handled the same. I got caught up in the purifi issue and I had the replacement parts in a week. Try getting that service from a big box vendor.

 

[peng]

Well, I agree with you, but you did not say you disagree of the definition of continuous, which was my point, not everybody agree on how amp should be specced, which was also my point.

I did not say anything about that part because I know some reviewers, probably Amir included but would like to hear from him, seem to use the continuous term to indicate the test signal it a continuous sine wave signal, not some kind of a pulsating signal. It may be too generalized to say the term "continuous" in the audio spec/testing world should mean continuous indefinitely. Wouldn't it be better to include terms such as continuous indefinitely, continuous for x seconds (or minutes, hours)? Or is it really necessary to say, unless otherwise specified, "continuous" shall mean literally continuous indefinitely.

Below is an example of how sometimes the term continuous is used, where it obviously did not mean "indefinitely", that is the "literal" meaning by definition.

Federal Register :: Request Access

Rated power shall be obtainable at all frequencies within the rated power band without exceeding the rated maximum percentage of total harmonic distortion after input signals at said frequencies have been continuously applied at full rated power for not less than five (5) minutes at the amplifier's auxiliary input, or if not provided, at the phono input.

 

[AdamG]

Very sure Buckeye’s call was a commercial one as he is savvy and is customer responsive. I will check with him on the technical aspects, but know he would send to Hypex for repair. As part of repair, Hypex would diagnose it.

If you run everything balls to the wall, hair dryer, air compressor, car/motorcycle engine, computer, power drill, Sander you name it. With no active cooling it will all blow up, melt and fail. If you want continuous max power out of something you had better install active cooling. How long did OP maintain full power until failure? Did he provide any additional cooling functionality? You can put a Car on the Dyno and discover Max HP, but you can’t keep it pegged for long before piston rods start launching.

We are getting far afield from the actual review yes. But this conversation is productive and educational. Unless OP @thin bLue has objections we are inclined to let this conversation continue? Please remain Civil and it’s all good

 

[PeteL]

I did not say anything about that part because I know some reviewers, probably Amir included but would like to hear from him, seem to use the continuous term to indicate the test signal it a continuous sine wave signal, not some kind of a pulsating signal. It may be too generalized to say the term "continuous" in the audio spec/testing world should mean continuous indefinitely. Wouldn't it be better to include terms such as continuous indefinitely, continuous for x seconds (or minutes, hours)? Or is it really necessary to say, unless otherwise specified, "continuous" shall mean literally continuous indefinitely.

Below is an example of how sometimes the term continuous is used, where it obviously did not mean "indefinitely", that is the "literal" meaning by definition.

Federal Register :: Request Access

Great, Come on I did not mean it to be literally infinite, In the litteral sense. You kinda prove my point about the semantics debate. I will also think that If the amp can do 5 minutes on a test signal at full power, most people here will agree that it can be specced at continuous, I think anyway. Even the post I was replying to did bring 5 minutes as reasonable. I honestly think we are saying the same thing.

 

[pma]

If you run everything balls to the wall, hair dryer, air compressor, car/motorcycle engine, computer, power drill, Sander you name it. With no active cooling it will all blow up, melt and fail. If you want continuous max power out of something you had better install active cooling. How long did OP maintain full power until failure? Did he provide any additional cooling functionality? You can put a Car on the Dyno and discover Max HP, but you can’t keep it pegged for long before piston rods start launching.

We are getting far afield from the actual review yes. But this conversation is productive and educational. Unless OP @thin bLue has objections we are inclined to let this conversation continue? Please remain Civil and it’s all good

I understand, but with a proper, even passive cooling with a proper heatsink, you can run the amp at full power continuously, unlimited time. The situation is changed when you want to make it small, which is the case nowadays. But then be honest and put it into specs.

 

[peng]

Great, Come on I did not mean it to be literally infinite, In the litteral sense. You kinda prove my point about the semantics debate. I will also think that If the amp can do 5 minutes on a test signal at full power, most people here will agree that it can be specced at continuous, I think anyway. Even the post I was replying to did bring 5 minutes as reasonable. I honestly think we are saying the same thing.

We are in agreement.

 

[GXAlan]

I credit @thin bLue for being the “Amir” of Korea. Just as Amirm showed us that high end gear can perform poorly on SINAD, @thin bLue has shown us “pretty good gear” can have “pretty poor protection circuitry”.

The reason this deserves to be part of the thread is that it is meeting to some degree the readership standard.

If I tried to showcase amp protection by slowly increasing humidity and then complained that the amp failed because it broke when I simulated rain at the level of one inch/2.54 cm per hour, people would say that was unfair/unrealistic.

Here, the readership recognizes that we are definitely in a gray zone at the very least, and many are supportive of the idea that you should be able to do what you advertise you can do.

The whole idea of reporting THD+N at 15 or 20 kHz when also talking about 20-20 kHz bandwidth is rightfully questioned by restorer-John, albeit it can be done with less finger pointing. Those measurements are just noise measurements. After all, if 15 kHz is your fundamental, then the first harmonic is at 30 kHz and the harmonics are measured only up to 20 kHd so the THD isn’t being measured.

For me, I have personal bias which I recognize. I bought the expensive PM-10 which is attractive and I believed in the reliability based upon brand and an interview where the engineers apologized for the launch delay. But looking at the service manual, there indeed is a lot of additional protection circuitry! Maybe this isn’t worth doubling the price and customers have to decide how much to spend on performance and how much to spend on reliability, and it turns out asking for both is expensive.

But this is a discussion that is science based. We already saw this with the Topping PA5, which failed under normal conditions and is acknowledged by Topping and led to the potted circuitry being reverse engineered. We are now seeing that “impossibly high output power” is too good to be true.

All we need to do is come to some agreement about ideal levels of transparency in advertising…

 

[Deleted member 48726]

If you run everything balls to the wall, hair dryer, air compressor, car/motorcycle engine, computer, power drill, Sander you name it. With no active cooling it will all blow up, melt and fail. If you want continuous max power out of something you had better install active cooling. How long did OP maintain full power until failure? Did he provide any additional cooling functionality? You can put a Car on the Dyno and discover Max HP, but you can’t keep it pegged for long before piston rods start launching.

We are getting far afield from the actual review yes. But this conversation is productive and educational. Unless OP @thin bLue has objections we are inclined to let this conversation continue? Please remain Civil and it’s all good

I would rather not my BMW motorcycle blew up on the German Autobahn with full throttle. Same with my car. They should last or otherwise they are faulty.

IR to tools there are some things like duty cycles and running time to consider which mostly is why there is "Pro" and "Hobby" models.

CPU / GPU in my PC should also be able to run 24/7 folding or mining at 100 % load. Otherwise they are faulty.

If I buy an amp that says 100 W continous power I would expect it to do so. Continously. Without interruption. If it lacks the cooling means to do so it is not built for 100 W continously. Then they should have sold the same amp as a 75 W amp.

 

[NTK]

CPU / GPU in my PC should also be able to run 24/7 folding or mining at 100 % load. Otherwise they are faulty.

If I buy an amp that says 100 W continous power I would expect it to do so. Continously. Without interruption. If it lacks the cooling means to do so it is not built for 100 W continously. Then they should have sold the same amp as a 75 W amp.

Why? They don't represent mine and just about anybody's use cases. The only situation I can think of that an amplifier will run at full rated power with a single frequency sine wave is on a test bench, which isn't the intended use case for an audio amplifier. The capabilities you mentioned don't come for free. Why should everyone be burdened with the extra cost for capabilities practically no one will use?

 

[tmtomh]

I would rather not my BMW motorcycle blew up on the German Autobahn with full throttle. Same with my car. They should last or otherwise they are faulty.

IR to tools there are some things like duty cycles and running time to consider which mostly is why there is "Pro" and "Hobby" models.

CPU / GPU in my PC should also be able to run 24/7 folding or mining at 100 % load. Otherwise they are faulty.

If I buy an amp that says 100 W continous power I would expect it to do so. Continously. Without interruption. If it lacks the cooling means to do so it is not built for 100 W continously. Then they should have sold the same amp as a 75 W amp.

I don't disagree with this, but I think some qualification is in order. (EDIT: as I was typing this, @NTK made a more forceful and concise version of this point just above.)

Your bike needs to be rock-solid dependable because if it's not you are likely to get seriously injured or die. Your stereo amp should not catch on fire or have its metal case be live of course, but aside from those scenarios there's nothing life threatening about an amp shutting down or its PSU dying.

I mention this not to make a general point, but rather for a very specific reason: the FTC standard for continuous power is not indefinite but rather a minimum of 5 minutes.

And since the FTC standard is a stick that some of our members regularly use to beat Class D amps with, it seems to me that we have to acknowledge that "continuous = indefinite" represents a moving of the goal posts just as Hypex's wattage rating is a moving of the goal posts compared to FTC. Just because "continuous now equals indefinite" moves the goal posts to a more rigorous standard does not automatically make it necessary, proper, or appropriate for determining whether an amp is "fit for purpose."

And in this narrow respect, I think @AdamG247 makes a good point: you can run many devices at the limit of their spec and they will eventually break down or stop working without a rest or without increased thermal management - and to my knowledge this has been true for at least some A/B amps for decades. We just don't necessarily know which A/B amps because there aren't (to my knowledge) a lot of systematic measurements and records of what happens if you run a 100wpc A/B amp at 100 watts for, say, two hours straight.

Again, I am not arguing that Hypex et al's topline power ratings are accurate as continuous power ratings, and I'm not arguing that they should get a free pass. And I'm definitely not arguing that vendors of complete amps should simply cut and paste specs for a module or PSU - they need to be providing accurate specs based on actual tests of their fully assembled models.

But we also know that Class D amps and Class A/B amps provide different types of extra power in different ways - Class A/B provides burst power, while Class D appears to provide extra continuous power from 20Hz up to somewhere around 5kHz. The only reason Class D's extra power is not seen as a benefit is because the modules' power ratings are spec'd too high.

 

[GXAlan]

CPU / GPU in my PC should also be able to run 24/7 folding or mining at 100 % load. Otherwise they are faulty.

If I buy an amp that says 100 W continous power I would expect it to do so. Continously. Without interruption. If it lacks the cooling means to do so it is not built for 100 W continously. Then they should have sold the same amp as a 75 W amp.

100%.

Again, I think the standard put in by the FTC needs to be voluntarily re adopted.

Why? They don't represent mine and just about anybody's use cases. The only situation I can think of that an amplifier will run at full rated power with a single frequency sine wave is on a test bench, which isn't the intended use case for an audio amplifier. The capabilities you mentioned don't come for free. Why should everyone be burdened with the extra cost for capabilities practically no one will use?

You don’t have to be burdened. You can get the Nc252mp, a used NC400 or NC500. There are tiered options for sure.

The analogy is a DAC with 120 dB SINAD versus 100 dB SINAD. Why pay extra when practically no one will use the extra THD+N? You’re right that you don’t need the power being advertised — but you really should not be advertising something that isn’t true.

 

[tmtomh]

100%.

Again, I think the standard put in by the FTC needs to be voluntarily re adopted.

The comment you are expressing 100% agreement with says an amp needs to be able to run at full power indefinitely. The FTC standard you are advocating for says an amp needs to be able to run at full power for 5 minutes.

 

[Sokel]

How all this ended up to power needs?
And if so the only condition that I would need to choose after determining my needs would be 20-20.000Hz continuous power (that means to me before shutting or lowering the output for thermal/current limiting/X reasons ) at a reasonable TDH+N under8/4/2 ohms load.
High peaks,headroom,"dynamic power" and such would be nice but I consider those as extreme conditions.

As some of my friends tease me about having "high" power output on my lows I always argue that I choose (along with my installer) a 2 X 280 watt power amp (out of the 2 X 680 watts stated for 90 seconds).And that makes things simple.

The main issue here is not that though.Issue is the protections should anything happens,from a high power demand to a power grid shutdown,etc.
In tested amp that failed.
That's what must concern us and how to solve it,thankfully we have members here with decades of experience.