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Post by me262 on Jun 17, 2014 16:56:25 GMT -5
Hi guys,
Let me tell you all what is going on.
I have a marantz 7701 -> XSP-1 (HTB) -> XPA-2, the marantz also sends the center, and surround channels to a UPA-500. Every piece of equipment that plugs into this system all plug into a Furman Linear Power Conditioner. Other things plugged into this system include a panasonic plasma via hdmi into the 7701, a Schitt Gungnir dac into the XSP-1, and an apple tv that plugs into the 7701.
I have always had interference whenever I run anything through the XSP-1's home theater bypass. I always assumed this was a ground loop, but even when using a cheater plug this only reduces the noise slightly. I recently re-setup my rack and ran wires a slightly different way and now have more buzz. I also at one point was picking up a radio station.
These recent occurrences seem to lead me to believe that this might not be a ground loop issue but rather electrical and rf interference on my interconnects. So what cables am I using? Mono-price XLR's for the XSP-1 portion of the signal chain and mono price rca's for the rest.
I am thinking about taking the plunge and ordering some BJC cables (Blue Jean cables) to redo the entire analog signal path of my system, any chance this could finally solve my problem or most likely not?
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Post by aud on Jun 17, 2014 17:30:29 GMT -5
Do you already own other XLR cables from different manufacturers that you can try first?
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Post by me262 on Jun 17, 2014 17:31:35 GMT -5
I do not sadly.
Let me also clarify, I have buzz coming from all of my speakers including the UPA-500's but it is not as bad as the xsp-1 HTB.
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Post by aud on Jun 17, 2014 17:34:54 GMT -5
I had to make sure. Monoprice had some problems awhile back with soldering the correct wires in the cable to the correct terminals on the connectors. Do you have a multi meter or a continuity tester?
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Post by redog on Jun 17, 2014 17:44:35 GMT -5
It is entirely possible that it could be a manufacturer defect. Just today I had to re-wire a gold line system that was wired wrong from the plant.
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Post by aud on Jun 17, 2014 17:45:07 GMT -5
Do you have a cable or satellite converter box hooked up. Didn't see one in your sig.
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Post by aud on Jun 17, 2014 17:47:49 GMT -5
It is entirely possible that it could be a manufacturer defect. Just today I had to re-wire a gold line system that was wired wrong from the plant. Unfortunately, I'm running into this problem more often. Now when I purchase new cables the first thing I do is a continuity test of the cable terminals. |
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Post by redog on Jun 17, 2014 17:51:54 GMT -5
It is entirely possible that it could be a manufacturer defect. Just today I had to re-wire a gold line system that was wired wrong from the plant. Unfortunately, I'm running into this problem more often. Now when I purchase new cables the first thing I do is a continuity test of the cable terminals. May or may not have something to do with outsourcing. |
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Post by aud on Jun 17, 2014 18:08:06 GMT -5
If you're pretty sure it's a ground loop you will have to turn your system completely off. Unplug the system or switch off from the Furman. Disconnect one wire and turn on system. Keep doing this sequence until the hum disappears. Hopefully it will. The last disconnect where the hum goes away is the offender.
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jlafrenz
Global Moderator 
I don't want to jump in, unless this music's thumping
Posts: 7,722
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Post by jlafrenz on Jun 17, 2014 18:40:16 GMT -5
I am a believer in BJC. I have had similar issues and the BJC took care of it. They are great cables.
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Post by DavidR on Jun 17, 2014 19:35:20 GMT -5
I had that problem after putting a groundwire to the digital coxial cable splitter outside the house. I also had audio and video components mixed on the same electrical outlet. Solution: electrically separated all the audio and video. Gave the audio its own dedicated circuit. Removed the ground wire from the cable splitter.
Problem solved.
It could also be a bad interconnect. I had that on my TT but only had the hum when using the TT.
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Post by hcsunshine90 on Jun 19, 2014 12:33:34 GMT -5
Hi guys, Let me tell you all what is going on. I have a marantz 7701 -> XSP-1 (HTB) -> XPA-2, the marantz also sends the center, and surround channels to a UPA-500. Every piece of equipment that plugs into this system all plug into a Furman Linear Power Conditioner. Other things plugged into this system include a panasonic plasma via hdmi into the 7701, a Schitt Gungnir dac into the XSP-1, and an apple tv that plugs into the 7701. I have always had interference whenever I run anything through the XSP-1's home theater bypass. I always assumed this was a ground loop, but even when using a cheater plug this only reduces the noise slightly. I recently re-setup my rack and ran wires a slightly different way and now have more buzz. I also at one point was picking up a radio station. These recent occurrences seem to lead me to believe that this might not be a ground loop issue but rather electrical and rf interference on my interconnects. So what cables am I using? Mono-price XLR's for the XSP-1 portion of the signal chain and mono price rca's for the rest. I am thinking about taking the plunge and ordering some BJC cables (Blue Jean cables) to redo the entire analog signal path of my system, any chance this could finally solve my problem or most likely not? |
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Post by hcsunshine90 on Jun 19, 2014 12:37:51 GMT -5
hey me262, I notice you have the music hall mmf-2.2 turntable. I also have that turntable. how do you like the ortofon blue cartridge? I just have the cartridge that the turntable came with, (the music hall tracker). also did you ever listen to your TT with the music hall tracker cartridge, or did you have the ortofon blue cartridge from the beginning?
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Post by me262 on Jun 19, 2014 12:53:19 GMT -5
I really like the ortofon blue, I did have the original cartridge and found it a bit lacking in comparison to the blue. I highly suggest that you go with the blue if you can.
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Post by hcsunshine90 on Jun 19, 2014 12:56:10 GMT -5
thanks for the quick reply, me262. this is consistent with what just one other reviewer said: the cartridge that comes with the mmf-2.2 is just so so. happy listening, john
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Post by hcsunshine90 on Jun 19, 2014 13:01:13 GMT -5
I really like the ortofon blue, I did have the original cartridge and found it a bit lacking in comparison to the blue. I highly suggest that you go with the blue if you can. hey , by the way: do you know the exact model name of the ortofon blue? on amazon they have one that is "ortofon stylus DJ E blue elliptical stylus phono cartridge stylus" for $52.99. is this the one? (how much did yours cost?) |
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Post by me262 on Jun 19, 2014 13:08:59 GMT -5
I really like the ortofon blue, I did have the original cartridge and found it a bit lacking in comparison to the blue. I highly suggest that you go with the blue if you can. hey , by the way: do you know the exact model name of the ortofon blue? on amazon they have one that is "ortofon stylus DJ E blue elliptical stylus phono cartridge stylus" for $52.99. is this the one? (how much did yours cost?) You want the audiophile ones, check out needle doctor, they are about $225 |
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KeithL
Administrator
Posts: 10,074
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Post by KeithL on Jun 19, 2014 14:57:33 GMT -5
The fact that the buzz got worse when you "re-ran the wires" suggests a few things:
1) Make sure that all your connectors are clean, and fit tightly in their jacks. (Oxidized or dirty connections will make you more susceptible to noise.) Likewise, if you do have a bad wire, or one with a bad solder connection inside, pulling on the wires can make it worse (or better).
2) Try and figure out how your wires are routed differently than before. Also try moving them around and seeing if the hum changes when you do. If the hum varies depending on where the wires are positioned, then that suggests that it's simply your interconnects picking up hum. There's no such thing as a perfect shield, so even perfectly good interconnects can pick up hum if you run them near power cables. Interconnects should always cross power cables at right angles, and should never run next to power cables if at all possible.
Hum picked up by wiring will almost always change when you handle and/or move the wires around. In contrast, if it's a ground loop, it should remain pretty much the same when you move the wires.
3) The change could be because of the relationship between two pieces of equipment - or cabling.... perhaps a preamp sitting on top of a power amp, or cables running over a power amp.
4) Check the details of what's plugged into what else (moving the power cables around, even to different outlets on the same power strip, can change grounding - and so could make hum worse (or better).
Note that Plasma TVs are notorious for generating electrical noise of various types... which could leak into the power lines, or interconnects. Also note that the sort of signals that run through HDMI cables tend to generate noise. it would be good to avoid having HDMI cables run near (or especially next to) interconnects.
Picking up radio stations suggests that either something is very poorly shielded, or something is prone to picking up interference through the air (an interconnect can act as an antenna).
It would also be VERY helpful to know if this happens to all channels, all of the time, with all sources - or just with certain combinations. For example, phono preamps are very sensitive, and so prone to picking up interference - and the wiring in turntables, as well as the cartridge itself, can all contribute to this problem (but, of course, this would only happen when playing records).
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Post by frenchyfranky on Jun 21, 2014 10:50:13 GMT -5
In many case the hum came from an input source, if it's the case you can just unplug one by one the source to identify the wrong one.
I had experience a bad soldering contact inside a RCA cable.
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Post by me262 on Jun 29, 2014 18:02:45 GMT -5
Hey Keith,
Thanks for your response, we have actually talked on the phone about my XSP-1 Home theater bypass hum. I am planning to re-arrand my audio rack, and when I do I will move all power cables to the left side the rack and all interconnects to the right, I guess I will then run the HDMI cables down the center of the rack. I use a Ferman 15 pfi, so everything should be grounded at about the same ground point, and my plasma screen is plugged into that unit in the video block.
So to try and give some help:
When just using the XSP-1. Balanced from my dac through the asp-1, to the sub and xpa-2 is more or less fine. At full volume I get a slight bit more noise then at any other volume level but this happened when I moved my cables around so I feel like if I re-cable that will go away.
On the phono pre, I get noise at about -30 with nothing playing, and it is noticeable from my listening seat at -25. With music playing it is fine to about -22, though I never have an erg to play louder.
When I run the dac into the xsp-1 and then out via processor loop to my headphone amp, I get no noise as long as the amp is plugged in via a cheater plug (bad practice I know, but I have no choice it seems).
The problem really sits in my Home theater portion. I have slight noise coming through all speakers that run from the 7701 to the UPA-500, but that is not audible till about +2 on the volume scale from the listening position. I then when switching my XSP-1 to HTB mode, have noise from the 7701->XSP-1->XPA-2 that is much louder by comparison to the noise coming from all other speakers. I still cannot here this noise from my listening seat until +2 and the noise does not seem to vary with volume till we get to +2. This noise has what sounds like a 60hz hum as a part of the overall noise coming out of it. Things going into the 7701 is a PC via HDMI (3 prong), apple tv via HDMI(3 prong), att cable box via HDMI (2 prong). All connectors from the 7701 are RCA for the pre-outs.
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