Jolida JD-100 New unit with bad HUM.....hum

Just a thought I forgot until now, when I bought my JD100 it replaced a 15 year old Philips CD carousel. The Philips only had a 2-pronged plug, the JD100 of course has a 3 prongged plug (ground). When I first hooked up the JD100, I had a tremendous humm. I e-mailed my dealer and he told me I may have a ground loop. I put a cheeter plug on the Jolida cord at the outlet and problem solved. I have since installed dedicated lines and no humm at all even with the grounded plug. I guesss I'm asking if the cdp that you replaced had a 2-pronged plug? You may be experiencing the same thing? Let me know.

Thanks Mijknarf,
My old cdp is indeed a 2-pronged plug (Yamaha carousel). Although I am not positive that the hum is not a problem of the supply power on my end and not an internal problem with the unit I don’t think it’s on my end. I have tried both standard utility power (110v) and a power system that incorporatea a 5 kva copper wound isolation transformer 230v primary and 110v secondary witch feeds a 125amp sub panel. The center tap of the transformer derives the neutral and ground and does not have a physical tie to the utility company, rather a grounding electrode system made of (4) 3/8” 8’ driven ground rods and develops the ground reference from that (no grounding or grounded tie no utility “noise”) 4 separate dedicated 20amp circuits serve my components each with #10 grounding conductor using #10 stranded wire from sub panel, terminated with sta-con spades connectors to Leviton hospital grade 20amp receptacles. The transformer is active and pulls almost 8 amps at idle so I installed a contactor ahead of the transformer with a 120-volt coil wired to a single pole switch to turn the system off when not in use. Although this system is not NEC compliant (don’t try this at home) is has worked wonders in terms of power quality and got rid of a nasty ground loop I had on my turntable for years. Nonetheless the Jolida when powered by the utility company or the transformer hums like…. er……. well it hums. Any problems with the reverse on your unit??? I did try removing the video connections to my HTR with no success. Thanks again!! T. J.

Call Chris at Parts Connexion and describe your problem. He is enormously helpful and friendly. I had to send back the first JD-100 I had modded from him because there was a problem with the volume in one channel. He had me Express mail it to him (at his expense) and replaced it with another express mailed to me the next day.

Holy cow! My degree is in Mechanical engineering so naturally, if I can't see it I can't understand it! My head is still spinning after reading your detailed response. I'll just let it go and assume that my little 3-pronged vs. 2 pronged response was as helpful to you as my wife asking me if a sharper pencil would help me with a particular difficult kitchen remodel last year! I'm sure the rest of us are curious to know what your dealer has to say tomorrow. It really is too bad because the Jolida is one fine player in it's price range. Good luck.

The Chili came out great. Needless to say I ate to much. I doubt they will boot us for Chili recipes, although if it gives the powers that be indigestion.....Hehe.

If you're like me, I have neat and tidy little boxes with all my leftover goodies. See if you have a powercord without a ground (the original Yamaha PC) and give it a try. Essentially lifting the ground. Of course if you have chased a ground loop off from your turntable you will be well able to track this one down. The AC setup BTW, is much better than mine, I can understand your frustration after such painstaking preparation.

I assume both channels are humming, which rules out a tube failure. Unless they both failed (what are the odds) or a catastrophic failure effects both outputs (I dont know, maybe). You could try out different tubes. I presume with the Mod package that you got upgraded tubes, so you probably have the stock tubes.

After RF hum from the cable, ground loops, and fragged tubes, I begin to run out of ideas. I am sorry you're having this trouble. I agree with Mijknarf, once you get the ghost out of this machine, I think you will be very pleased.

As far as the Chili, its pretty much standard fare chunky style. I dice a couple of Jalepenos and saute them in olive oil in the bottom of the pot. Open a window if you try this. The fumes are distressful to say the least.