[dizzyorange]

Can someone explain what 12-0-12 means, and how it is different from a standard 24volt DC adapter?

Also, does Elpac (or anyone else) make a high quality adapter that is 12-0-12 and also 3-prong DIN? (for use with an X-Can V3).

Thanks for any responses.

 

[ericj]

12-0-12 means that the transformer has a 24-volt center-tapped secondary. You can use it as either a 24v supply or a 12v supply or with both positive and negative regulators you can use the center tap as 'ground' and have -12 and +12 out of the same trafo.

You can use a transformer with dual 12v secondaries for the same job, but you can't sub a center-tapped trafo for a dual secondaries trafo.

 

[dBel84]

It is also ( usually ) in reference to AC voltages of the secondary windings of a transformer and not the DC output of a regulated power supply, which is what ericj has, quite correctly referred to. ..dB

 

[sejarzo]

Quote:

Originally Posted by dBel84 /img/forum/go_quote.gif It is also ( usually ) in reference to AC voltages of the secondary windings of a transformer and not the DC output of a regulated power supply, which is what ericj has, quite correctly referred to. ..dB

I also presumed that the 12-0-12 voltage requirement for the X-CANv3 referred to a PSU with dual DC outputs, one +12VDC, one -12VDC, but that is not what the MF web site shows as the required supply for the X-CANv3.....

From the spec page for the X-CANv3:

"Power requirement: 12 - 0 - 12Volts AC 500mA (via mains adaptor supplied)"

That is odd, isn't it, that one would specify an AC supply that way? It's not as if there is positive AC and negative AC, right??????

But here's the respective info from the X-PSUv3 page:

"Power outputs: Four, each 12 - 0 - 12Volts AC 20VA"

The same info is shown in the pdf versions of the manuals available on the MF site for those products.

Dizzyorange, does your current MF "cheap" wallwart state that it supplies DC or AC on its faceplate?

And does anyone have an idea of why MF would use a 3 pin arrangement to provide two "different" hot 12 VAC leads?

Has anyone looked inside an X-PSU? Is it just a multitap toroidal transformer?

 

[tomb]

Quote:

Originally Posted by sejarzo /img/forum/go_quote.gif I also presumed that the 12-0-12 voltage requirement for the X-CANv3 referred to a PSU with dual DC outputs, one +12VDC, one -12VDC, but that is not what the MF web site shows as the required supply for the X-CANv3..... From the spec page for the X-CANv3: "Power requirement: 12 - 0 - 12Volts AC 500mA (via mains adaptor supplied)" That is odd, isn't it, that one would specify an AC supply that way? It's not as if there is positive AC and negative AC, right?????? But here's the respective info from the X-PSUv3 page: "Power outputs: Four, each 12 - 0 - 12Volts AC 20VA" The same info is shown in the pdf versions of the manuals available on the MF site for those products. Dizzyorange, does your current MF "cheap" wallwart state that it supplies DC or AC on its faceplate? And does anyone have an idea of why MF would use a 3 pin arrangement to provide two "different" hot 12 VAC leads? Has anyone looked inside an X-PSU? Is it just a multitap toroidal transformer?

It's not odd, per se - especially if the amp involves tubes. Often, the smaller secondary supplies are used for the lower voltage heaters, while combining the two hot legs provides a basic voltage for boosting higher for B+ tube voltages. The SOHA is only one example of an amp that does just this - if you use a separate supply. It can be fed from a walwart configured with three wires - one 15VAC, 0 (center tap), and a second 15VAC - hence, 15-0-15. (This is how I do it, anyway - much cheaper than all that AC Mains junk in the case, and the separation distance for the walwart even removes the need for a toroid.) In your case, sounds like the voltage is 12V, but nothing different other than that.

 

[mrarroyo]

Well here is the inside of the X-PSU V3. As you can see not much to it.

 

[sejarzo]

Maybe MF should just call it the "X-Toroid-in-a-Can."

Sure makes it clear that the other X-Series components must do their rectification, filtering, and regulation internally........which begs the question as to why the X-PSU should make a significant difference?