Buckeye Nc502mp Review (6 Channel Amplifer)

[Doodski]

2007, Hell that's a spring chicken. I've got Adcoms here that are circa 1995.

I used to provide Adcom warranty service and the stuff was a joy to work on. I had zero ideas that the stuff would last this long. There was not very much to repair and when we got a piece in it was my responsibility to service it so I got all of it. Mostly pre-amps with a broken solder joint or a pot that needed a squirt of cleaner and lube. Nothing really serious.

 

[antcollinet]

I have an old, circa 2007 Halcro MC70 Class D amp that was rated at 200 watts per channel x 7 with all channels driven. It was well reviewed at the time, and still works fine. Are these new modules a big step up from that older Class D Halcro Design? The amp still works fine but I'm tempted to update to an 8 channel NC502MP Buckeye just because it's been so many years.

Ncore is probably a step up in measurements - just from the tech. Whether you will hear any benefit though is another matter : the MC70 is already rated pretty well for THD+N.

I would try to resist that itch. If you can't it is definitely one for try before you buy - being careful not to do what I did, and believe it sounds better because you want to upgrade.

 

[ruzun]

I think I will stick with the Halcro MC70 until it starts to wear out in some noticeable way. There are new Hypex modules due out soon I think the NCx500. So maybe in a year or three I will revisit the issue. I noticed the 8 channel NC502 based Monolith just went on sale for $2149 though, which seems pretty cheap. I'm not having any issues though so I'll stick with the Halcro for now since it might not be a noticeable difference getting a newer amp.

 

[Sal1950]

I noticed the 8 channel NC502 based Monolith just went on sale for $2149 though,

That includes free shipping, a very good price!
But do you need it? Your call. LOL

 

[Angsty]

I think I will stick with the Halcro MC70 until it starts to wear out in some noticeable way. There are new Hypex modules due out soon I think the NCx500. So maybe in a year or three I will revisit the issue. I noticed the 8 channel NC502 based Monolith just went on sale for $2149 though, which seems pretty cheap. I'm not having any issues though so I'll stick with the Halcro for now since it might not be a noticeable difference getting a newer amp.

The Halcros were formidable. I think your decision to stick with it is a good call. They might outlive these Hypex modules and it’s not likely you’d hear a difference.

 

[Rottmannash]

Who made the modules in the Halcro amp?

 

[Labjr]

Who made the modules in the Halcro amp?

They were designed by Bruce Candy of Halcro.

 

[Head_Unit]

It might also be interesting to see 6x600W supplied from wall outlet plug …..

I had the same thought, but it's just not going to happen unless your speakers are quite inefficient or your neighbors really far away. Or everyone is really drunk. Even playing with a mere 6 dB of dynamic range would make the power 900W* = probably wouldn't blow a breaker.

*mmm but if the peaks...something seems off about the exact math, can't figure it due to Mexico/Colombia taking up too much mental bandwidth. Arriba coqueros! Anyway unclipped would not blow the breakers methinks.

 

[pras1011]

The measured watts are terrible compared to what hypex state they are.

 

[Jdunk54nl]

The measured watts are terrible compared to what hypex state they are.

Do you mean the 500w spec. Iirc that number is at 1% (40db line on the graph) and then this exceeds it by 100w to achieve nearly 600w. Amir looks for the “knee” and uses that for max spec where as most manufacturer amp specs are at 1% unless otherwise noted.

 

[pras1011]

I thought using 1% thd to measure watts was cheating? Just like using a 1khz instead the entire frequency from 20hz to 20khz.

 

[antcollinet]

I thought using 1% thd to measure watts was cheating? Just like using a 1khz instead the entire frequency from 20hz to 20khz.

Why - if it is stated and consistent it is fine. Just compare like with like.

And the reason is that 1%thd from clipping of peak transients is barely audible.

 

[pras1011]

OK thanks. What's the true 8 ohm figure then?

Is there any sound quality differences between the nc502mp vs nc500?

 

[peng]

OK thanks. What's the true 8 ohm figure then?

Is there any sound quality differences between the nc502mp vs nc500?

As explained by tonycollinet, and you already know, you can go with the 1% THD+N point, 1 kHz.

Or, obviously, you can choose your own from the following graphs. That's probably the main reason why people come to this site, for the much more detailed tests.

For example, if you want to see the frequency dependency test, you can refer to the NC252MP's and assume (reasonably..) the NC502MP would most likely behave similar, just at higher output levels:

So based on the info available, I would say the buckeye 6 channel NC502MP probably can do 170 W @ -80 dB 20-20,000 Hz based on the NC252MP's test shown below. This is of course just an educated test of my own. Amir has been doing such a good job testing amps, it would be even better if he makes the frequency dependence test standard for all amps (including preamps).

 

[pras1011]

I would also guess its about 170 watts at 8 ohms and therefore conclude that these amps are not as powerful as people suggest.

I think ratings at 1% thd and 1khz frequency response is very misleading so as to give a higher watt figure.

 

[peng]

I would also guess its about 170 watts at 8 ohms and therefore conclude that these amps are not as powerful as people suggest.

I think ratings at 1% thd and 1khz frequency response is very misleading so as to give a higher watt figure.

It is up to the individual to read the specs, Hypex provided the specifics for their power amp modules, manufacturers may use their own selected power supplies and heatsinks and that will affect their actual measured outputs under different test conditions:

 

[pras1011]

So NC500 can do 400 watts at 1khz and 1% thd. And therefore this figure would be substantially lower at 0.01% thd and 20hz to 20khz?

What does Continuous Output Power mean?

 

[peng]

So NC500 can do 400 watts at 1khz and 1% thd. And therefore this figure would be substantially lower at 0.01% thd and 20hz to 20khz?

Probably, you would have to see the frequency vs output curve for the actual numbers. More later..

What does Continuous Output Power mean?

Good question, this is one of those specs that frustrate people like me who are obsessed with accuracy, definitions etc.. Like "power consumption" specs, different manufacturers seem to use definitions of their own, and worse still they usually don't even tell you what their basis are.

Some of the choices, or preference you can choose from, based on my search on the internet would include but not limited to the following:

1) "continuous output power" may mean the output power measured at a specific sine wave frequency that is a continuous signal, so that could range from just a few seconds, 10 seconds, 10 minutes, or literally continuous, i.e. forever!!

2) It could also mean using a continuous sine wave signal at a specified frequency, usually 1 kHz, for a specified duration. If the duration is not specified, it could be anything, for example if the manufacturer follows the FTC rule that is not compulsory as far as I know, it will be for not less than 5 minutes.

Note that Hypex does not provide "continuous" ratings. I read it somewhere that they leave such spec to the manufacturers since the real (i.e. literally) "continuous" rating would depend on the cooling provided, such as heat sinks.

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.

Now, back to the Hypex amps, again just the Hypex amp modules based on Hypex data sheets:

For the NC400:

If you look at the red curve, it would be about 400 W, 4 ohms, 1 kHz, and a little more for 6 kHz. The 6 kHz curve is good because it would include the typically dominant 2nd and 3rd harmonics. You can find out the same about the NC502MP by looking through the downloadable data sheets.

I wish all power amp manufacturers would provide as much details as Hypex, for their midrange and up models, sadly, very few do.

 

[pras1011]

Specs are below.

So NC500 can do 400 watts at 1khz and 1% thd. And therefore this watts figure would be substantially lower at 0.01% thd and 20hz to 20khz?

Hypex figures are misleading.

 

[peng]

Specs are below.

So NC500 can do 400 watts at 1khz and 1% thd. And therefore this watts figure would be substantially lower at 0.01% thd and 20hz to 20khz?

Hypex figures are misleading.
View attachment 236316

I posted the graphs that allow you to read the distortion figures at as high as 6 kHz test signal. Which figures you find misleading, mislead to what? Not challenging your claim, you raised some interesting points and I am just trying to help if I could.