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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
discopants
149 posts
 

fo.q ta 32 tape, it's 0.3mm thick has anti static properties too, a bit like furutech ncf. Dampens vibrations too, also comes in ta102 which is 1mm thick.

 

highly reccomended can be bought on eBay from Japanese sellers very reasonably.  

corelli
996 posts
 

Eric, re-read my post.  You're not the only one to notice this.  Your bigger problem is the poorly designed Wattgate.  If you are afraid to change the IEC on the amp(which may NOT fix the problem) , just try a better plug such as the one I listed.

erik_squires OP
16,128 posts
 

Thanks @Corelli !

I agree the Wattgate feels wonky.  After extensive testing with the Mouser inlet I agree the replacement of the inlet is the way to go.

When I first built the AC cable I used a Parts connection plug.  It was always a little loose so I thought (incorrectly) a Wattgate plug would fix the problem. It did not.  Both plugs do significantly better on the new inlet that's sitting on my workbench behind me.

erik_squires OP
16,128 posts
 

PS -

I’ve done some totally not scientific testing of the contact overlap. Using a multimeter and shorting out the plug I’ve determined that from the point that the plug reaches minimum resistance to the fully seated position is 5 mm. That is, you have to pull the plug out 5 mm before the resistance would rise above zero. That’s a lot better than what I’m experiencing on the Luxman which seems to disconnect at 1-2 mm.

erik_squires OP
16,128 posts
 

PPS -
 

Yeah, I'll use a 3 pin plug, and add a little heat shrink on the inside so it looks purty.

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