Something else came to mind. In some of the pictures of the D-06, I see the AC inlet and it is a standard IEC 3 prong inlet with 3 legs. The power cable has the regular iec for the amp side but the plug is a 2 prong plug. In my D-06, the ground leg has been removed on the amp ac inlet.
Having lived in Japan, I know 3 prong ac receptacles are not standard. Just thinking out loud if any of this has any reason why Luxman might have disabled the line phase sensor...
Having lived in Japan, I know 3 prong ac receptacles are not standard. Just thinking out loud if any of this has any reason why Luxman might have disabled the line phase sensor...
They use such sockets not to render expensive IEC power cords unusable with their product and disappoint prospective buyers I would think. But they had probably pulled the ground prong because they decided they want their particular machine ground lifted? They have had their afterthought sessions with best grounding/lifting the model it rather shows.
I suppose so. I think it is time now to just enjoy the music. The CD player sounds really great. I might shoot for the D-08 eventually.
I can think of one. With a 2 wire plug, how do you 'check' line phase? Your only reference is the signal ground and even that may not be 'grounded'. The current from the neon lamp would have to return through the signal system - an intentional ground loop AND given the threshold nature of neon lamps could create quite a buzz in the audio.
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My understading is that the sensor tells you if the hot and neutral is swapped when plugged in. I installed a 150k ohm resistor and the lamp does now work and lights up when you plug the plug in the "wrong" way. What I don't understand is why would this matter to the audio with AC? I have many gear that has just a 2 prong and I really can't hear any difference whether it is plugged in one way or another. And I've read some theory papers stating that the polarity has no effect on functionality of the gear whatsoever written by APC.
I am thinking that at one point, Luxman did have the D-06 with a 3 prong power cable and it was grounded. Then somewhere along the line, they decided to float the ground. The power cable that comes with the unit has a 2 blade plug although the unit side has a standard iec plug. But as I mentioned earlier, on the unit, the ground blade in the iec receptacle is not there. Perhaps at this point, they decided to disable this sensor as well?
I see your point. The return of the neon lamp goes through the XLR audio cable ground? And this has a potential to cause noise. I haven't experienced any noise with the sensor enabled but I will keep note. Thanks for your reply.
I thought I had mentioned in the power transformer one side of the input coil goes to the neutral the other the hot lead. If the winding closest to the core goes to the hot lead more noise will transfer via stray capacitance to the chassis. So the sensor makes sure that the neutral wire is the start of the cores primary windings.
You did. It sounds like a great feature but I think I've only seen this on the current Luxman gear. I wonder why others don't do this if it really makes a difference. Esoteric and Audio Note machines don't have this which I was also considering before getting the Luxman...
I suspect there may be a patent involved.
The hot wire has voltage with respect to the neutral which is grounded. Connecting a neon lamp from the hot to a capacitor to earth will cause it to light. Any stray metal or human body will do.
Well, I tried it with just the unit plugged in as well as it being hooked up to my linestage using balanced cables.
The D-06 comes with a 2 prong power cable. A nice one at that.
LUXMAN | PRODUCTS | REFERENCE LINE CABLE JPR/JPC, REFERENCE POWER CABLE JPA-15000
It is the JPA-15000 model power cable.
You have to touch the metal plate on the sensor to test the phase. I suppose your finger becomes the ground??
If I look at the circuit, the neutral coming in from the ac inlet goes straight to a resistor (which was missing) and then straight to the sensor unit. I don't see any connection with the hot leg.
I got to the bottom of this. Luxman did indeed disable this sensor. The reason being it did not meet CE qualifications. As to which specific qualifications, I don't know but Luxman is going to eliminate this feature going forward.
Some U.S. models including D-06 have this sensor disabled. Hence, it is not in the manual and erased from the diagram picture.
However, I wish Luxman would make this info more public because a customer who is detailed can be confused as to why the sensor is there but does not work (like me)...
Some U.S. models including D-06 have this sensor disabled. Hence, it is not in the manual and erased from the diagram picture.
However, I wish Luxman would make this info more public because a customer who is detailed can be confused as to why the sensor is there but does not work (like me)...
Ok to clear a few things up:
The sensor indeed determines if the phase is "correct". The idea is to have all your equipment connected the same way.
It has nothing to do with grounding or whatever.
In large parts of Europe it's common to have reversible plugs, even if they are grounded. So there is no real way of knowing if all your equipment is in the same phase, unless you check it.
(It's kinda moot because it all gets converted to DC anyway, but whatever)
About the pulled plug in the IEC socket. The device is double-isolated which means that it's not connected to ground. It will have a logo of a square with a smaller square inside on the back signifying this.
Double-isolated devices are NOT grounded. You can use a grounded lead if you want, but it won't make any difference.
edit: http://en.wikipedia.org/wiki/Appliance_classes#Class_II
The sensor indeed determines if the phase is "correct". The idea is to have all your equipment connected the same way.
It has nothing to do with grounding or whatever.
In large parts of Europe it's common to have reversible plugs, even if they are grounded. So there is no real way of knowing if all your equipment is in the same phase, unless you check it.
(It's kinda moot because it all gets converted to DC anyway, but whatever)
About the pulled plug in the IEC socket. The device is double-isolated which means that it's not connected to ground. It will have a logo of a square with a smaller square inside on the back signifying this.
Double-isolated devices are NOT grounded. You can use a grounded lead if you want, but it won't make any difference.
edit: http://en.wikipedia.org/wiki/Appliance_classes#Class_II
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Hi
My Luxman SQ38 use a 2,2M resistor in series with lamp...
Thanks. European voltage is 220v so I think it would be different in a U.S. model. But I think anything above 100k ohm will be fine.
I wonder what CE qualifications this sensor not qualify for.
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