Buckeye Hypex Nc502mp Multichannel Amp Teardown

[sam_adams]

Speaking of #1, I also like to see the anodization sanded off until bare metal shows. Here they are just scuffed:

That grounding post is implemented incorrectly. At the bottom of the post there should be a nut with a 'toothed' star washer underneath it to cut through any anodizing or surface finish. Then there should be—in this order—'toothed' star washer, circular lug, 'toothed' star washer, nut. The 'toothed' star washers cut throught any oxide or coating and when properly sized, create a low resistance, solid, gas-tight joint to the chassis, ground lug, and wire.

 

[sam_adams]

@Doodski, those are great burnishers. The stainless wire will cut through any anodize or surface finish in a flash and produce a bright, bare metal finish. Much better than mild steel wire burnishers. Still need to do the correct "nutstack" for the ground lead though.

 

[Buckeye Amps]

That grounding post is implemented incorrectly. At the bottom of the post there should be a nut with a 'toothed' star washer underneath it to cut through any anodizing or surface finish. Then there should be—in this order—'toothed' star washer, circular lug, 'toothed' star washer, nut. The 'toothed' star washers cut throught any oxide or coating and when properly sized, create a low resistance, solid, gas-tight joint to the chassis, ground lug, and wire.

I used to use a washer underneath the lug, but after the first tear down back in 2020 it was suggested to have the lug directly contacting the bare case metal as a washer can affect grounding performance (I think Amir pointed to an article at the time discussing this). I will look back through that tear down thread.

 

[Buckeye Amps]

@Buckeye Amps In this picture the sanding looks amateur and poorly finished as well it might not be into the bare metal. When I was assembling the electrical systems of oil drilling rigs I provided my own tools and found some very nice stuff and this is one that you will maybe like a lot after you use it. It is for burnishing surfaces for a proper electrical connection. It is meant to be used in a drill. It will fix the appearance and the integrity of the connection in this pic.

Apologies, I missed this!

Thank you, this seems like a perfect tool to implement. Much appreciated!

 

[sarumbear]

May I ask whats the block I highlighted is for?

 

[Jdunk54nl]

May I ask whats the block I highlighted is for?

That looks like the trigger relay to me, he uses automotive grade relays.

 

[Dmitri]

Buckeye,

I firmly believe there are a lot of mass market and far more expensive amps out there that don’t have the build quality you provide.

I’ve said this in a previous Buckeye thread, but it deserves repeating:
I admire your desire to improve your product and take advantage...with a very open mind, of the many positive suggestions and experience available to you here at ASR.

Kudos to you!

Maybe I’ll get lucky and my venerable old Rotel 1095 will blow up. If so, I’ll be placing an order for sure...and trying to figure out what to do with all that extra space left over in my audio cabinet. ; )

 

[sam_adams]

I used to use a washer underneath the lug, but after the first tear down back in 2020 it was suggested to have the lug directly contacting the bare case metal as a washer can affect grounding performance (I think Amir pointed to an article at the time discussing this). I will look back through that tear down thread.

A properly hardened toothed washer will cut into both the nut and the underlying metal exposing bright, clean metal. If the washer flattens out when tightened down, it's crap. You can tell if it's good if you remove the nut after tightening and it's scored by the teeth of the washer you know it's working properly.

 

[sam_adams]

he uses automotive grade relays.

I sincerely hope they're not Lucas relays . . .

 

[Buckeye Amps]

I sincerely hope they're not Lucas relays . . .

Can confirm they are not

 

[Buckeye Amps]

May I ask whats the block I highlighted is for?

The relay for the 12v trigger

 

[TLEDDY]

I sincerely hope they're not Lucas relays . . .

Ah yes: “Lucas…Prince of Darkness”

 

[sam_adams]

Can confirm they are not

Thank goodness!

 

[001]

Ah yes: “Lucas…Prince of Darkness”

View attachment 161904

Ah, yes, and that reminds of 'Phil', close enough to the prince of darkness

 

[Bruce Morgen]

With regard to "spades can come loose," I can recall only one incident where an industrial-grade (as opposed to the cheap stuff you get in a Harbor Freight assortment) "FastOn" connector in a speaker circuit actually failed, and that was on one terminal an old JBL's tweeter, from corrosion due to the speaker having been stored in a damp basement literally for years.

 

[sam_adams]

Ah yes: “Lucas…Prince of Darkness”

View attachment 161904

That's not enough:

 

[restorer-john]

1. I checked the grounding screw on the Hypex amplifiers and two get routed to the safety ground of the IEC outlet but the top module does not. The resistance was under 1 ohm for the two modules but a few hundred ohms for the top module. Assuming this is recommended practice from Hypex, the case anodization needs to be sanded off underneath.

The Hypex modules have the screws marked with a white ring/line around them and they not connected to the chassis/spreader plate and are insulated. SMPS primary side. All the other mounting screws are connected to the plate using plated through vias with an RC pair on each screw going to the module 0V.

The capacitors are 10n and the resistors 1R in series on each screw.

Like these:

 

[pma]

What is the size/AWG of the wires from PCBs to speaker binding posts?

 

[IVX]

Capacitor brand complaints incoming in 3, 2, 1....

not sure if I understand that but let me please say about Suscon alcaps, it is high quality and isn't cheap stuff. As OEM/ODM they have produced Rubicon's alcaps 15 years ago. If you'll ask me for the decent Chinese caps that name would be the first I call.

 

[DS23MAN]

"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."

These modules are also used in loudspeakers, the more goop the better!