hummmmmmmm

[slowGEEZR]

Ok. I finally got around to setting up my system in my new home in San Antonio. Part of it anyway. I've connected the Pioneer Elite DVD, CD combo player, the BAT BK-P5 Phono stage, VPI Scout, Jolida JD1000RC integrated amp and the Musical Fidelity X-CAN v-3 headphone amp. The ML's are not connected, as I have new speaker cables ordered. My current biwires are too short. The X-Can is connected to the fixed preamp output of the Jolida. Everything is plugged into a Monster HTS 5100 MX II power center. Well, make that everything was plugged into the power center. I've since plugged the amp directly into the wall power, but there is no difference to the problem.

The problem? It sounds like a 60 cycle hum coming from my Sennheiser headphones. I think it is originating from the amp, as when I unplug it, the hum goes away. It doesn't seem to matter if the DVD combo player is on or off. Now, I didn't have any hum coming from the amp before I moved from Virginia and I carefully packed and moved the amp in my car for the trip down here, so I don't think there is anything different with the amp. I did make sure to ground the amp to the Scout and the Scout to the BAT, but haven't yet tried grounding it to a real Earth ground.

I am using inexpensive interconnects to the headphone amp, but they shouldn't be the problem, as I used them before. I don't think the problem could be because I have no speakers hooked up to the amp; especially since I only put the amp in standby mode in order to listen to the headphones. The next step is to hook everything up to the Krell 400xi and see if the problem disappears. If so, that should confirm the Jolida is the source, or at least has a problem with the current set up. Does anyone have any other ideas? Thanks, Steve.

 

[Nik]

Can't comment about the hhhuuuuummmmmmmmm but I can say welcome to Texas- and remember its y'all not you all.

Bob asked "Do y'all want to hear some awesome speakers?" :music:

If your new cables need a new home let me know- I am in the market!

Nik

Edit: Sry- did you hook everything up the way it was before the move?

 

[slowGEEZR]

Ok. I've hooked up the speakers using some cheap cabling while I'm waiting for the speaker wire to arrive. First, I changed out the Jolida for the Krell and still had a hum. This time, I noticed that it was only when switched to the DVD player. There was no hum when switched to the turntable. Progress! Since this was the first time I've had my system together since about the beginning of April, I took this opportunity to listen to an album. I had almost forgotten how good the Martin Logans sounded! Prior to setting up the system, I vacuumed the speakers very thouroughly and carefully for the very first time. I can't be sure that made any difference, but they sure sounded fine. Also, the room is much larger than the listening room I had back in VA.

The other reason I listened was to see how the Krell sounded in this new environment. It sounded very articulate and powerful, with lots of slam.
I then reconnected the Jolida and listened to the same album again, Joni Mitchell, "Court and Spark". I bought this album when it was first released and it is in pristine condition. It is a very dynamic and clean recording. It is also eminently more listenable via the Jolida rather than the Krell to my ears. The Krell seems to portray her voice as a little shrill at times, while the Jolida portrays her voice in a sweeter manner. Which is more accurate? I don't know. Truth probably lies somewhere in between. I know that I'll take sweet over shrill any day.

Back to the hum. My next step is to move the DVD player to another location and reroute the interconnects. If that doesn't cure the problem, I will then connect a different player via the same interconnects. If that doesn't do it, I'll swap out interconnects. I sure hope the interconnects aren't the problem. They are my favorites. Suggestions welcomed. Thanks,
Steve.

 

[MiTT]

Is the DVD player also hooked up to your cable tv in any way shape or form (even at the TV)? If so I would suspect that as the culprit. Cable tv is notorious for introducing ground loops.

 

[IWalker]

Agreed. 60 cycle hum is almost surely a ground loop...and the issues I've had with it have generally been related to cable connections. There are cheap connectors you can get that will screw into the cable connection and fix the issue.

 

[slowGEEZR]

Yes. It is due to the cable TV. I connected the cable box to the TV via component video cables and disconnected the 75ohm cable they had connected. Now I am getting true HDTV. But, I still have a hum whenever any cable (audio or video) from the DVD player touches the TV, as long as the cable box is connected. So, for now, I've left the DVD player disconnected from the TV. At least I have music now! Now to find those cheap connectors. Radio Shack, here I come! Thanks guys. - Steve

By the way, I have the bedroom TV hooked up with component video cables from a DVD player and the cable TV box and have no hum at all. Go figure.

 

[IWalker]

Yeah, some components are succeptible to ground loop hums, while others are not.

http://www.epanorama.net/documents/groundloop/video_isolation.html

That has a good explanation, I think...and should give you something to isolate the cable ground from the rest of the system. (links at the bottom) Didn't have time to look through completely...so I'm not SURE this will help!

 

[MotorToad]

Be careful, these ground issues can be some pretty significant voltages, especially if it's a bad cable box or other powered device. I had a laser disc player (yeah, the 12" monster discs! ) that I quickly found could send 60-70 Volts (guessing by the sting) through the UHF connection.

 

[slowGEEZR]

Thanks for the link and for the voltage warning. Laser disc player? Ha ha. I've still got mine, but I haven't really thought about hooking it up. I've only got about ten laser discs! -Steve

 

[Pcar928fan]

Laser disc player? Ha ha. I've still got mine, but I haven't really thought about hooking it up. I've only got about ten laser discs! -Steve

You saw mine in the rack when you were over! I have about 75 LD's I guess, so I figured I should go ahead and hook the damn thing up! Most of my discs are not repeats in my DVD collection either, which is pretty odd!

 

[JonFo]

You saw mine in the rack when you were over! I have about 75 LD's I guess, so I figured I should go ahead and hook the damn thing up! Most of my discs are not repeats in my DVD collection either, which is pretty odd!

And mine too, my trusty old CLD-97 is still going strong avert twelve or so years (I lost count). Still have about 100 discs, with strangely enough, few repeats as well.

About the Hum, the king daddy of all hum eliminators are the Jensen Transformers.

So if it's your cable TV, or your long unbalanced run to the Sub, or whatever, they have the fix for the problem.

BTW- their SUB-1RR subwoofer isolator is the ticket for runs to a sub that is on a different leg of the house wiring and suffering from hum.
The other smart move is to use an unbalanced to balanced transforer, and gain the benefits of balanced wire for the long run to a sub as well. Use a PC-2RX (R= RCA input, X=Balanced XLR output), as it will also convert to Balanced and keep the RF/EMI junk from also getting in the sub signal path.

 

[slowGEEZR]

You saw mine in the rack when you were over! I have about 75 LD's I guess, so I figured I should go ahead and hook the damn thing up! Most of my discs are not repeats in my DVD collection either, which is pretty odd!

I don't think I'm going to hook mine up at this house. When I buy a house in the Austin area and have a dedicated room I probably will. It's amazing how much gear I have that is in boxes! I've even got a 32 band per channel equalizer that I bought way back in the '70's. I guess if I ever have some room anomalies that I can't sort I'll hook it up. lol

 

[slowGEEZR]

And mine too, my trusty old CLD-97 is still going strong avert twelve or so years (I lost count). Still have about 100 discs, with strangely enough, few repeats as well.

About the Hum, the king daddy of all hum eliminators are the Jensen Transformers.

So if it's your cable TV, or your long unbalanced run to the Sub, or whatever, they have the fix for the problem.

BTW- their SUB-1RR subwoofer isolator is the ticket for runs to a sub that is on a different leg of the house wiring and suffering from hum.
The other smart move is to use an unbalanced to balanced transforer, and gain the benefits of balanced wire for the long run to a sub as well. Use a PC-2RX (R= RCA input, X=Balanced XLR output), as it will also convert to Balanced and keep the RF/EMI junk from also getting in the sub signal path.

Thanks for the info. If I get annoyed enough at not having the ability to play DVDs in the living room, I'll definitely check out the Jensen transformers. Currently, I can watch DVDs in two bedrooms. It's amazing just how much stuff there is to do when you move to a different state! I just completed getting my cars, trailer and bike safety inspected, insured and registered. For now, I'm finished messing with the audio system.