Buckeye Hypex Nc502mp Multichannel Amp Teardown

[High Power Dude]

Who is a good company to buy a Hypex amp from? Audiophonics?

Here you go:
VTV Amplifier

Nord Acoustics

March Audio

ATI Amplifiers

 

[Matias]

Who is a good company to buy a Hypex amp from? Audiophonics?

Add Apollon to that list. And if stereo only, boXem and March too.

Apollon Audio Hypex Based Class D Handbuilt Amplifiers

Hypex based Class D amplifiers handbuilt with highest precision and care. Experience sound that brings a smile to your face with Apollon Audio Class D Hypex based amplifiers combining Class A sound with Class D efficiency and precision. Choose between monoblock, true dual stereo and multichannel...

www.apollonaudio.com

boXem | audio - Index

HiFi made in Luxembourg

boxem-audio.eu

Shop - March Audio

March Audio Online Shop

www.marchaudio.com

 

[Colonel7]

Here you go:
VTV Amplifier

Nord Acoustics

March Audio

ATI Amplifiers

Don't forget Apollon
Edit: @Matias beat me to it

 

[Dmitri]

I’d wait for the Buckeye. Kinda like having gotten to know the builder.

 

[HammerSandwich]

damn i was just eying down a monolith 7 amp for the new onkyo reciever i preorderd... Now i see this amp!!! WTF do i do!!!

It's a simple decision process if you follow Hammer's Official Gear-Acquisition Checklist, already updated for your convenience:

1. See that the upcoming Monolith Ncore is 8x200 at $3000.
2. Notice that 4 channels of NC502MP cost $1049 from Buckeye while the Monolith 3x200 is $1300.
3. Compute that 1049 + 1300 = 3000 - 651
4. Rationalize ordering one of each.

 

[pseudoid]

I really like the 'upside down' XLRs, as I am too lazy to go behind the rats' nest in the rear.
Accessing them from the front would be a delight. I wonder if that was one of the reasons for putting them downside-up?
Are those heat-sink fins below the PCB_A (nearest MAINS in) and PCB_C, but not under PCB_B?
Rotating PCB_C 180degrees will possibly reduce AC wiring length by half. This heavier gauge (18awg?) left-over pair can then be used for the output (20awg?) harnesses.
The length of the green wire from PCB_C would also be reduced...

 

[Qbd]

Are those heat-sink fins below the PCB_A (nearest MAINS in) and PCB_C, but not under PCB_B?

Pretty sure they are cutouts in the case for airflow.

Rotating PCB_C 180degrees will possibly reduce AC wiring length by half.

After my adventure with hiss from a NC502MP amp, I prefer they always be oriented with the PSU towards the front. Much easier to keep signal cabling well away from noisy PSU parts that way.

 

[poopy]

I would definitely use same length wires for each PCB and shielded wires

 

[howard416]

I am sure someone has already mentioned this, but the Faston style quick disconnects are not "spades" and are quite reliable when installed properly. The issue is usually more on the side of the crimp, where if the tooling isn't good enough or there's a mismatch with wire gauge and connector, you can have a lack of proper copper "flow" and bonding/gripping of the wire strands. I'm actually quite interested in the fact that the ones used by Buckeye appear to be gold-plated, because the majority of them are usually tin-plated only.

@Buckeye Amps A washer like this https://www.mcmaster.com/90895A205/ when used between the head of a screw and the sheet metal panel, with a nut (of correct size) on the other side of the sheet metal panel, is sure to give an excellent electrical bond even if the sanding is not the best. The rated hardness is higher than almost any typical steel sheet, and higher than most types of commodity fasteners, so it will cut through the surface of the metals and give a nice air-tight "bite" when torqued to spec; plus, with the inherent spring quality of the washer, it will handle vibration and thermal cycling very well (again, when torqued properly - NOT to "flattened" condition). I like to use these, along with a fully-threaded cap screw, to give myself a fully-bonded stud for grounding purposes. Then, at any point on the stud, I can use a ring terminal with double-nut and get a foolproof grounding point. However, if you plan to keep doing this for a while, you may want to look into a stud welder that can do copper-plated steel studs. No question about these...

I suggest using zinc-plated steel fasteners (both in general as well as when using these washers for audio electronics) as there can sometimes be unwanted contact resistance from the chromium oxide layer on SS material. Note: Belleville (disc) washers are used in one direction only, so be careful.

My 2 nuts cents. Edit: phew, what a typo

 

[Astrozombie]

Wasn't there a controversy with VTV in the past? Shoddy assembly from someone who bought one ^^^^^

 

[Bruce Morgen]

Wouldn't good quality (highly conductive), tight-fitting (with respect to the hole in the case) sheet metal screws reliably cut through any powder coating or anodization without special washers, rotary grinding, or having to be careful of torque?

 

[Doodski]

Wouldn't good quality (highly conductive), tight-fitting (with respect to the hole in the case) sheet metal screws reliably cut through any powder coating or anodization without special washers, rotary grinding, or having to be careful of torque?

Nope. They come loose.

 

[Doodski]

and... One does not want a sharp protruding from the bottom of the cabinet...

 

[Bruce Morgen]

Nope. They come loose.

Sheet metal screws with blunt ends are readily available -- and I'm not sure they'd come loose any more often than washerless machine screws/nuts would in a static application like home audio gear, as contrasted to something that gets banged around like an aluminum screen door or a guitar amp.

 

[Doodski]

washerless machine screws/nuts would in a static application

The thermal cycling loosens the sheet metal screws and then a bad ground occurs or even thermal runaway if there are clamped output transistors involved. I've worked in extruded aluminum and in threaded to sheet metal screw conversions and they both never worked out long term. If there is flexing involved I doubt the sheet metal screw will hold up in sheet metal. I think for a chassis a machine screw with locking nut and washers is best or has been mentioned a threaded stud spot welded onto the chassis. It takes seconds to apply with the proper tool.

 

[Bruce Morgen]

The thermal cycling loosens the sheet metal screws and then a bad ground occurs or even thermal runaway if there are clamped output transistors involved. I've worked in extruded aluminum and in threaded to sheet metal screw conversions and they both never worked out long term. If there is flexing involved I doubt the sheet metal screw will hold up in sheet metal. I think for a chassis a machine screw with locking nut and washers is best or has been mentioned a threaded stud spot welded onto the chassis. It takes seconds to apply with the proper tool.

OK. Thanks for sharing your experience.

 

[Walter]

Wasn't there a controversy with VTV in the past? Shoddy assembly from someone who bought one ^^^^^

Yes. I have read at least one report on here that the problems have been mostly or entirely corrected, but since the manufacturer does not choose to participate in this forum, unlike Buckeye, it is impossible to know for sure. Buckeye and March Audio seem to get the highest marks for quality of workmanship of all the Hypex amps--although there may be some European brands that are just as good and I just have not read the reviews as thoroughly. (And please note that I am simply reporting what I have read. I do not have the necessary knowledge to evaluate the workmanship myself.)

 

[bravomail]

Examining the branding of the capacitors we find that the ones in the amplifier are from Aishi and those in the power supply, Sus'con:


BTW, I am always surprised by the amount of goop hypex puts on their amps. They are good to keep vibrations down and keep failure during shipping low. But I must confess I had not seen them put on transformer in that manner. I wonder if it is there to keep transformer whining down as a post measure. The goop makes repair more of a pain by the way as you can't just desolder and pull the part out.

PS capacitors r Sus
Goo reminds me of climate protection. Maybe to use in outdoor applications?

 

[DonH56]

As others have said, there should be a toothed or otherwise locking washer on the connections. I'm 100% with @Doodski on seeing sheet metal screws loosen over thermal cycles and just over time. Not always, probably due to the metals and such, but often enough...

 

[AdamG]

As others have said, there should be a toothed or otherwise locking washer on the connections. I'm 100% with @Doodski on seeing sheet metal screws loosen over thermal cycles and just over time. Not always, probably due to the metals and such, but often enough...

I believe but could be wrong, that Buckeye does use some type of locknut on the underside of the ground connector. Maybe @Buckeye Amps can confirm or correct me on this?