Good Afternoon,

This is the situation: I wish to mod my SX-1010 by adding an IEC port, and remove the aux outlets. From what I see, and have gleaned from searching the forum threads, the flat disk cap from the main fuse holder, and the small resistor from the aux outlets constitute the floating ground. The second fuse, wired from the main fuse holder to the switched aux out serves that outlet. With the removal of the aux outlets and the installation of the IEC port, I would assume that those items ( the resistor and flat disk cap, along with the second fuse) would not be necessary, and can be eliminated. Are these assumptions correct?
I have not found a thread (to this point) that indicates what the orientation should be of the wires to the IEC port (white wire to the transformer & green wire to the switch), and what would be the best point to ground the IEC port to the chassis. Can anyone point me to the proper search query to find these answers, or provide me with this info?

The whole idea is that with a non-polarized cord, the side that is connected to the chassis throught the 2.2 meg resistor or death cap can be swapped depending upon both hum and chance errors in the building supply wiring.

Actually grounding the chassis (to the green wire) would introduce ground loops iiac.

you could wire the thing with an IEC, skip the green ground wire (shudder, leaves open assumptions for whoever comes afterwards) and add a switch to choose which side of the chassis is connected through the resistor and/or the death cap.

To be completely correct the grounding of all the exposed metal would be to the green wire, while having ABSOLUTELY no connection to the actual amplifier signal or power grounds.

All this is a can of worms best left unopened.

I just looked at the schematic for a panasonic dmr-ez27p dvd recorder, and the primary circuit is COMPLETELY isolated from the ground and ALL exposed metal. There IS NO ground wire, it is a 2 wire cord, and is expected with both pins of the ac plug shorted together, supposed to have between 1 to 5 million ohms of resistance to ANY exposed metal. When the cord is plugged in, ANY exposed metal should have no more than 0.75v rms measured across a 1500 ohm resistor to a cold water pipe ground. A live tester (simpson model 229 or equivalent) should show LESS than 500 microamps of leakage current.

The 1010 (and just about all vintage Japanese electronics) use the chassis for signal return paths internally. Grounding it is a bad idea.

So aside from the grounding issue, the IEC installation process itself is OK? I still want to be able to upgrade my power cord

If you don't mind hacking up the back panel, knock yourself out. Personally, I've passed on otherwise desirable gear because someone had added an IEC setup. I want nothing to do with mods that included someone I don't know using a hacksaw/jigsaw. And I'm far from a believer that there's anything to gain. :no:

I am only going by my experiences with various power cords on my main rig. I have tried at least 15 different types and brands of power cords that go from DIY Chris VH cords, and lower level Monster, up to Purist Audio Design Dominus cords, both cryo and non-cryo versions. They almost all changed the performance in some manner, some better, some not so. The most common change on the better cords was a lower noise floor, and a tightening of the bass (like the difference between being hit with a 1 gal pail of water Vs. a water balloon of 1 gal size). Another change I have heard, although not with all upgraded power cords, is a greater sense of 'air' or space around the individual elements within the soundstage.
I really like my SX-1010. My foot taps when I listen to music through it. The unit I am considering the mods for is a second one. I am just interested in seeing how much more performance can be obtained through small changes. I had not planned to cut or hack up the rear plate - I had intended to have a new back plate made, and install my changes there. Besides the IEC port, I want to upgrade the RCA jacks and replace the current speaker connections with something like Edison-Price binding posts.
I both respect and admire EchoWars and MarktheFixer for their level of knowledge, and their willingness to help and share that knowledge with individuals like myself. That is one of the things that makes this site all that it is.
If anyone is curious about my power cord experiences, you can read about them here:
http://newaudiosociety.com/cgi-bin/yabb/YaBB.cgi?board=reviewsequipment;action=display;num =1122138804

http://newaudiosociety.com/cgi-bin/yabb/YaBB.cgi?board=reviewsequipment;action=display;num =1182802380

http://newaudiosociety.com/cgi-bin/yabb/YaBB.cgi?board=cables;action=display;num=111068474 9

Well then, I guess I won't go into my own opinions on what I think is audio-silliness (and yes, there are quite a number of others who disagree). But I will say that, on a 35-year-old piece of electronics, the power cord is the least of your worries.

Whatever small performance boot you could possibly get from changing a power cord (and I'm a long way from believing that there's anything at all to this), it would pale next to the gains that can be easily heard and measured from a proper restoration of the receiver (new electrolytic caps, weak transistors replaced, switches and pots cleaned, new relay installed, offset and bias adjusted).

IF there's anything to be gained with a power cord swap, I'd think it would be with a new piece of gear already running at its full potential, or with an older piece which has been thoroughly restored (and not many techs understand the real meaning of that word). I'd think that a cord swap would make a lot more sense when trying to squeeze that last bit of performace out of a receiver once everything else has been attended to. Otherwise it's kinda like putting 109 octane gas in your '66 Dodge Dart that hasn't had anyone look under the hood in the last 25 years and expecting hit the dragstrip & turn low 12's in the quarter.

The changes I would like to implement would be in addition to a proper restoration. The last e-mail I received from you (outside of communication through the board, and your 'My Waiting Queue, and Philosophy of Repair in General') indicated that my SX-1010 was in your to-do queue, and you would let me know when you were ready and able to begin work on it, so my unit could be shipped to you in a timely manner.
I have no problem agreeing that there is a progression that makes sense in modifications and upgrades. I like to consider myself a thoughtful and thorough individual. To this point and to that end, all I have done is to solicit feedback and attempt to collect information regarding the direction I thought I would like to go.
I appreciate your input Glenn. You have probably forgotten more than I will ever know about servicing, restoring, and treating these old units we are interested in. The ability to dip into that pool of information is why I belong to this board.

Gotcha...

If I've told you you're in the repair queue, you certainly are. I did not recognize your AK name as one who was awaiting repair (said queue growing by the day, and I'm crappy with names anyway).

Perhaps I should have also warned you that I'm a notorious naysayer about things like expensive power cables and Über-expensive IC's. But, all that is my own opinion, and is certainly not shared by a great many other AK members. I just tend to gravitate towards tweaks that make sense to me.

But I wasn't kidding about adding the ground. It would be the cause of much grief.