Hypex Ncore

[Julf]

It is connected to the shield of the input cable, which is connected to pin1, which jumps to the outer metal tab of the xlr connector and jumps to my chassis which is also connected to earth. So pin1 shield is common to nampon and the entire chassis.

Just as a test I might consider disconnecting the connection to the xlr connector ground (and thus isolating NAMPON/signal ground from the chassis ground).

 

[robbbby]

will try that after work, thanks Julf.

 

[mangew]

Mabye a really stupid question but still have to ask.

How to connect a power on switch? i have this one: High Current 40A 125V 10A 250V Power Switch | eBay and an IEC inlet: New Sonar Gold Plated IEC Inlet Fuseholder Sonarquest | eBay

Have never built an amp or something like ncore.

 

[ajst2duk]

That IEC inlet looks nice - the switch not so much. You will just need to wire the switch in series from the live terminal from the IEC (the one that comes after the fuse).
I warn you need to be VERY careful if you have not much electrical experience.

 

[Julf]

i have this one: High Current 40A 125V 10A 250V Power Switch | eBay

Ah, another audiophile willing to die for his hobby

I suggest you get a proper switch that satisfies western safety standards, instead of that less-than-safe piece of audiophoolery. That narrow gap between the poles is an accident waiting to happen. Do you feel the power switch will affect sound quality?

 

[mangew]

I have decided to go for a regular not so "fancy" black switch from a local seller.

 

[Julf]

I have decided to go for a regular not so "fancy" black switch from a local seller.

Good call! Maybe donate the fancy one to somebody doing a steampunk installation?

 

[Erlend Sæterdal]

NCORE VERSUS L 7 MOSFET

Hi I made this amp for 2 friends. One for the guy I made a NCORE for. Afterwards I made it for the One who bought the NCORE . Everbody think it is a much better amp Class AB MOSFET L7 Audio Power Amplifier Boards Kit Dual Channel 300 350W X2 New | eBay

 

[ro9397]

Hi I made this amp for 2 friends. One for the guy I made a NCORE for. Afterwards I made it for the One who bought the NCORE . Everbody think it is a much better amp

"Everybody" is sure a lot of people! I'm sure all Ncore owners will dump their amp based on this post...not.

 

[Julf]

Hi I made this amp for 2 friends. One for the guy I made a NCORE for. Afterwards I made it for the One who bought the NCORE . Everbody think it is a much better amp Class AB MOSFET L7 Audio Power Amplifier Boards Kit Dual Channel 300 350W X2 New | eBay

I guess it proves you are better at 1980's technology than at 2010's technology...

 

[Erlend Sæterdal]

I guess it proves you are better at 1980's technology than at 2010's technology...

You do not need to prove anything for me Julf. You have done more then enough.

 

[DeJ]

Hey everyone, can someone clear this up? In the NC400 guide, figure number 2 for an xlr connection: #1 on the xlr goes to the chassis, #2 and 3 are the pos and neg. And the other wire in the diagram is shown connecting to the chassis…is that the braided shield wire or the nAMPON wire? If it’s the braided shield wire, where does the nAMPON wire attach too?

Question 2, Is the nc400/smps600 grounded to earth? Can someone explain why the nc400 xlr is grounded to the chassis but thesmps600 ice is not?

And finally  question 3, The smps600 has one standoff touching the chassis for EMI reduction. How does that create a drain if the smps600 is not grounded to the ice? Wouldn’t that make the chassis radiate EMI?

Thanks everyone! Looking forward to getting these built!

 

[Julf]

Hey everyone, can someone clear this up? In the NC400 guide, figure number 2 for an xlr connection: #1 on the xlr goes to the chassis, #2 and 3 are the pos and neg. And the other wire in the diagram is shown connecting to the chassis…is that the braided shield wire or the nAMPON wire? If it’s the braided shield wire, where does the nAMPON wire attach too?

It is the braided shield, but you can connect nAMPON to it too, if you don't use nAMPON to swithch the amp off/on.

Question 2, Is the nc400/smps600 grounded to earth? Can someone explain why the nc400 xlr is grounded to the chassis but thesmps600 ice is not?

Depends on your definition of "earth". There is a ground plane on the nc400, connected to power supply ground. It can, but does not need to be, connected to chassis, and the chassis can be connected to mains earth, or not. The recommended way is to not connect the chassis to mains earth - but make sure you understand the class II construction implications - otherwise connect safety earth (for safety, not signal use).

And finally  question 3, The smps600 has one standoff touching the chassis for EMI reduction. How does that create a drain if the smps600 is not grounded to the ice? Wouldn’t that make the chassis radiate EMI?

I am not sure what "ice" refers to. Why would connecting the smps600 earth to the chassis cause EMI radiation?

 

[DeJ]

oops, ice is a typo. I meant to write, IEC Power Inlet. The thing the power cord attaches too. If the power cord is not grounded then the smps600 is not grounded and the chassis can radiate EMI because there is no ground drain. Right?

 

[Julf]

oops, ice is a typo. I meant to write, IEC Power Inlet. The thing the power cord attaches too. If the power cord is not grounded then the smps600 is not grounded and the chassis can radiate EMI because there is no ground drain. Right?

The smps600 is still grounded to the chassis, and the chassis contains the radiation (not that there is much in the first place). The mains earth connection is there only for electrical safety reasons.

 

[DeJ]

Doesn't the IEC that attaches to the power cord have to be grounded for the smpa600 to be grounded? Thanks.

 

[Julf]

Doesn't the IEC that attaches to the power cord have to be grounded for the smpa600 to be grounded? Thanks.

Depends on your definition of "grounded". There is a common signal ground reference between the boards inside the chassis. That common ground can be connected to mains earth for safety reasons, but it doesn't need to be.

The nc400 input circuit is a differential input, so it doesn't care about ground (OK, to be very precise, it doesn't care about ground very much - the common mode rejection ratio is 55 dB).

 

[DeJ]

Thanks Julf!

 

[mangew]

A question when i assemble a nc400 amp, shall i groun the XLR connector to the chassi. I see on pictures some seems to do and some doesn´t. And shall the XLR and IEC share grounding point. Some seems to do and some not.

What is to prefer?

 

[Speedskater]

For those of us who don't have Class II safety tested components. The IEC Safety Ground should be connected to the chassis near the IEC connector. The XLR Pin 1 should be connected to the chassis at the XLR jack. Typically these connectors are in different areas of the chassis.