[jtwrace]

That should be fine. DPST would probably be appropriate if you ever intend to use balanced AC power.

So I'm wrong?

[TomS]

Balanced power puts 60 volts on the neutral and 60 on the hot with respect to ground so you should switch both legs.

[TomS]

...and I'm not an AC power expert, but it seems logical to me to do that.

[jtwrace]

Balanced power puts 60 volts on the neutral and 60 on the hot with respect to ground so you should switch both legs.

...and I'm not an AC power expert, but it seems logical to me to do that.

I must be missing something then.  Where does Balanced Power come in with the Hypex units?

[TomS]

For example, if you plug them into a BPT 3.5 like mine.

[jtwrace]

For example, if you plug them into a BPT 3.5 like mine.

OHHHHHHH.

[mkcarnut]

Ahhh...got it...so if I am just running A/C in from my wall, I use SPST breaking the hot line with the switch (just as I would wiring a light in my house which I have done hundreds of times).  If I am using something like the BPT 3.5 I would worry about "balanced A/C power".

Thanks much gents!

FYI, I am working on a layout for an unusual setup...a wall-mounted aluminum/wood case combo.  Please watch for my sketches to appear in another thread.  I think that would fit in the "build" thread with this being step #1 of my build...planning the layout and case...so watch for it there over the next couple days.  I'd love input on the approach I am thinking of.  I've been looking at cases and nothing is really what I want...so with prompting from rclark, I've been getting creative in my solution.

Mark

[srb]

While the balanced power of units like BPT, Equi=Tech and others sounds like a good idea for common mode noise rejection, a safety concern arises if the power is not switched and/or fused in both legs, which would be easy to implement in DIY but would not be present in most factory built components.

Article 647 of the National Electrical Code, which outlines the use of 120V line-to-line / 60V to ground power, further states that it is only permitted for "commercial or industrial occupancies" and "restricted to areas under close supervision by qualified personnel".

?

Steve

[bhakti]

I would always recommend using a DPST switch on the mains regardless of your implementation.  The circuit it is plugged into can be wired incorrectly or as I just found out recently, your power cable can have the polarity reversed.  So, why take a chance with the SPST?  It is not that much more in work or expense.

[6rs]

Hi
I purchased two NCore 400 modules along with the corresponding power supplies and Siliconray cases.
My plan is to use a Metrum Octave Dac as source. Now, instead of using XLR sockets, would it be possible to  attach RCA plugs to the supplied input cable? Or, even more directly, to solder the wires of the cable to the Octave board? What would I do with the shield and that extra black wire? Any advice would be appreciated. Thanks, Bruno

[Phil]

someone who knows a thing or two about thermodynamics told me that aluminum is great at dissipating heat if it is painted or dyed black.

Any comments on the relative dissipation capacity of black vs. natural?

[genjamon]

I suspect what is being assumed with the black thing is that it will be more effective at long wave reradiation. Black color is black because it absorbs all wavelengths of visible light, but this usually means the substance reradiates light at a lower frequency, longer wavelength in the IR band or further.

If coating aluminum enhanced the thermal radiation, this effect would add to heat dissipation by merely conductivity between the metal and the surrounding air.  It seems plausible to me there is some effect to what you're suggesting, but I have no idea to what degree. It could be quite minor.  It would depend greatly on how warm the material gets as to how much energy might be reradiated.

Of course, this is kind of speculation on my part. Others on here may know more about the physics.

[*Scotty*]

The increase in efficiency available from painting heat-sink radiator assemblies black is valuable when you are trying to remove heat from a space vehicle or satellite in a vacuum where radiation is the only way that a body can loose excess thermal energy. Of course radiative cooling only works in the absence of solar radiation impinging on the black heat-sink assembly.
 Cooling by convection is not possible in a vacuum.
Scotty

[cab]

radiative heat transfer depends on the emissivity of the object that is hot. A black object has a higher emissivity and will radiate heat better. How much better depends on several factors, temperature difference being the largest. It is a 4th order effect.

[mkcarnut]

Just confirming my understanding of grounding and wiring to the XLR connector...it looks like there's been quite a lot on that already, but I want to make sure I understand what was previous written...please let me know if I have it right or not (my modules should be here to install next week!).

First, on the Amp's J9 to the XLR, from what I hear, the drawing provided by nCore in Figure 2 on Page 12 of their instructions is a bit confusing as to "which is pin 1, 2, 3, or 4" relative to how the J9 really looks (as viewed from page 10's "11.2 Front view/pin numbering").  But, if I follow J9 pin definitions from Page 10, the J9 pin 1 goes to XLR pin 2, J9 #2 to XLR #3, J9 #3 goes to nothing (unless I am using nampon), J9 #4 to chassis ground.

Second, XLR pin #1 goes to chassis ground.

and finally, the ground on the power in goes to chassis ground.

Did I get that all correct?  Many thanks for confirming or correcting!

Thanks,

Mark

[cab]

nampon has to be connected to chassis ground to take the amp module out of standby.

[mkcarnut]

Now I'm confused...just to confirm:  The nampon is J9's pin 3, per section 7.3 Page 5, and Figure 2/page 12 shows J9's pin 3 not connected to anything but J9's pin 4 connected to chassis.  Do both Pin 3 (nampon) & 4 (ground) of J9 go to chassis - or do I have something else incorrect in my head?

Thanks,
Mark

[cab]

one of the 3 signal wires to the xlr is the shield wire that goes to pin 1 which is also connected to ground. The nampon connection needs to be connected to ground in order for the amp to come out of standby. Most people put a switch between the nampon pin and ground so they can put the amp into standby by lifting it from ground.

[Atlplasma]

Now I'm confused...just to confirm:  The nampon is J9's pin 3, per section 7.3 Page 5, and Figure 2/page 12 shows J9's pin 3 not connected to anything but J9's pin 4 connected to chassis.  Do both Pin 3 (nampon) & 4 (ground) of J9 go to chassis - or do I have something else incorrect in my head?

Thanks,
Mark

There are a couple of videos on YouTube that can clarify how you solder an xlr connection. One of those might be helpful.

[mkcarnut]

Thx - I will look for the videos, and I will also e-mail Hypex w/the question.  But, if anyone has a link to the video or a direct answer to my question, I would appreciate it.

Back to cab...per your response, "one of the 3 signal wires to the xlr is the shield wire that goes to pin 1 which is also connected to ground. The nampon connection needs to be connected to ground in order for the amp to come out of standby."...can you explain?  I see nothing from Hypex which says this.  Are you saying that the wire I say goes to ground (J9, pin #4) should go to ground AND the nampon connection (J9, pin #3) ALSO goes to ground?  Maybe their drawing in Figure 2/page 12 is wrong...but they do not show that.  They show J9/pin #4 going to ground & J9/pin #3 (nampon) not connected to anything, and this is where I am confused on what they show vs. what you say.  If you can clarify, that would be great.

Thanks!

Mark