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My Luxman Integrated has AC Inlet Envy

I love my Luxman 507ux, it does so many things right, so soon after I got it I built a shielded power cable as an upgrade to the relatively plain cable that came with it.

To make a long story short, after trying out a number of different cables and female IEC plugs it seems the AC inlet has prongs which seem too short. For sure, the Luxman has no ground pin. I'm sure that this means it's not required, so that’s not an issue. What is an issue is that even a Wattgate plug, which are famous for a tight grip, can’t stay in. Even a little wiggle can disconnect the amp.

It seems either or all of these are true:

  • The missing ground pin is keeping plugs from feeling very grippy
  • The pins are too short
  • The pins are too thin

If I play with a cheap power cord, it seems like the AC doesn’t connect unti lthe very last 2 mm of travel of the plug. This seems wrong.

I bought a cheap replacement inlet and it just feels so much better. Meaning, I can feel the plug grip the pins much earlier, and they all grip much better.

Anyone else have issues with Luxman inlets??

 

PS - I absolutely insist on building my own power cables. This is my hobby not yours so please stop trying to convince me my problem is that I didn’t buy your boutique brand.

 

erik_squires
erik_squires OP
15,704 posts
 

Thanks @Ryder I guess it’s possible my particular unit, the original UX, not UX II version of the 507, got a bad inlet.

It has no ground pin, so locking plugs are useless, and even if they are, the short contact distance between the plug and inlet has to change.

I am going to change this inlet. I have one from Mouser (3 pin) I can use right now or I can order a Fancy Furutech from Parts Connexion.

I just think it’s weird I’m the only one who had this problem.

It seems many who reply are missing the part about SHORT CONTACT DISTANCE. Let me try to draw this out:

=== Luxman IEC inlet

....========= Plug

====== Cheap Mouser IEC Inlet

 

In the diagram above you see the Mouser sourced inlet has much more overlap with the plug contacts. Gluing the plug or bending the contacts inwards doesn’t increase the contact distance.

This is not your normal loose plug problem. :) Again, imagine you go to plug in your coffee maker and notice the pins are half as long as they should be.  I might be able to keep it attached to the wall by tape or bending the pins but neither really solves the contact area problem.

 

imhififan's avatar
imhififan
2,122 posts
 

It seems many who reply are missing the part about SHORT CONTACT DISTANCE.

The inlet on your L-507UX is a C18 (2 prongs), the pin height should be 12mm. A C14 inlet is 3 prongs, the two pins height are 12mm and the ground pin is 15mm.

Have you measure it?

 

 

 

imhififan's avatar
imhififan
2,122 posts
 

I bought a cheap replacement inlet but it’s not yet in the Luxman. I just bought it to test fit my cables and it seems to do a lot better than what’s in the Luxman both electrically and mechanically.

Seems like replace the inlet in your Luxman is the solution. No?

 

bolong
381 posts
 

My Anticables plugs have good connectors but the stiffness of these cables can sometimes make them sag enough to affect contact. Lately, I have been making loops from tape that first wrap around the cable just behind the plug and then are brought to adhere to the top of the chassis enclosure and tensioned enough to resist gravity. Same approach with HDMI cables which often have poor contact as well.

Of course, these are not issues with pin "grip" so much as they are issues with the weight of the cables.

erik_squires OP
15,704 posts
 

@imhififan

 

Have you measure it?

 

I will after I pull it out! :)

 

Seems like replace the inlet in your Luxman is the solution. No?

 

Yes, that's why I'm about to replace it.

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