Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
i have never had my transporter 'play nice' with ANY preamp i have used. i always get a hum when i add in a pre. it disappears when i go straight into my amps. -- ratso Martin Logan Vantages - Wyred for Sound SX-1000 monoblocks - Blue Circle BC-21 preamp - Slim Devices Transporter - APC H10 power conditioner - Cables by Me! ratso's Profile: http://forums.slimdevices.com/member.php?userid=11493 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
mmg_fan;307180 Wrote: Phil ok, it seems that I should get my amp serviced. Or perhaps simply hang onto my Lavry...when I go digital out from the TP to my Lavry(and XLR out from the Lavry to amp)...all 3 devices plugged into the same power bar..the problem also disappears. From what you say, am I wrong in supposing shoddy workmanship in the case of my Jolida hybrid amp? On a related subject, do you think 'power conditioners' are snake oil, or a worthwhile investment? I invested in one of the Monster Power boxes,(yeah i know not a popular brand)mainly for protection for my audio and plasma screen. Part of it was a sale of about half price but it turned out to be quite a nice piece of equipment. Not a power regulator but has separated filters for audio and video. I didn't expect much other than it probably would save me from huge power gains (ie lightning). Any audio gains are probably due to wishing but the video gains actually were very nice. I used to have pixelating (sp?) quite often but now I never seem to. So all in all it does give me some comfort plus improved tv. -- Nonreality *-If the rule you followed brought you to this, what good is the rule.-* Nonreality's Profile: http://forums.slimdevices.com/member.php?userid=15723 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
Phil ok, it seems that I should get my amp serviced. Or perhaps simply hang onto my Lavry...when I go digital out from the TP to my Lavry(and XLR out from the Lavry to amp)...all 3 devices plugged into the same power bar..the problem also disappears. From what you say, am I wrong in supposing shoddy workmanship in the case of my Jolida hybrid amp? On a related subject, do you think 'power conditioners' are snake oil, or a worthwhile investment? -- mmg_fan mmg_fan's Profile: http://forums.slimdevices.com/member.php?userid=9157 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
Noise from grounding problems can almost always be solved by judicious use of transformers. However, the root of the problem is often the ground topology inside the audio equipment itself. There are some ways to reduce the potential for grounding problems when designing audio equipment: 1. Use a low value resistor (I use a 4.7 ohm 1/2 watt carbon resistor) between the protective AC grounds and the signal grounds. This is a very high resistance when compared to the resistance of the ground wires, so practically all of the voltage from the stray AC currents which cause grounding noise builds up across this resistor, rather than the ground wires. 2. In some cases, an audio ground can be actively driven by a unity gain op-amp stage. This allows it to provide a ground reference, but it moves the noise polution caused by the stray AC currents to the DC supply rails, rather than the audio ground. Usually noise rejection is much better in the supply rails. 3. Star ground topology is a time honored way of reducing the common resistance across which grounding noise can build up. 4. Use components and circuits in the power supply which reduce the stray capacitance which causes stray AC currents in the first place. For instance, a power transformer with non-concentric windings or Faraday shields. -- Timothy Stockman Timothy Stockman's Profile: http://forums.slimdevices.com/member.php?userid=8867 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
mmg_fan;307180 Wrote: Phil ok, it seems that I should get my amp serviced. Or perhaps simply hang onto my Lavry...when I go digital out from the TP to my Lavry(and XLR out from the Lavry to amp)...all 3 devices plugged into the same power bar..the problem also disappears. From what you say, am I wrong in supposing shoddy workmanship in the case of my Jolida hybrid amp? On a related subject, do you think 'power conditioners' are snake oil, or a worthwhile investment? Hi there! Power Conditioners...well. it all depends on the quality of your mains supply in the first place. I suggest you find a sympathetic dealer or a sale/return arrangement and try it. However, IME you need to spend a few days with these devices - the quality of the mains can be very time dependant - it all revolves around what else is on your supply (nearby industry for example). I find my system sounds slightly more engaging at 3am... (unfortunately, the rest of the household disagrees!) I didn't know that the ground loop disappears with the DAC in the chain... that opens a whole new can of worms. That might exonerate the amp, in which case I'm lost (these things are very hard to diagnose by remote!) -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal...SB3+Stontronics PSU - Altmann JISCO/UPCI - TACT RCS 2.2X with Good Vibrations S/W - MF X-DAC V3/X-PSU/X-10 buffer (Audiocomm full mods)- Linn 5103 - Linn Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Townsend Supertweeters, Kimber Chord cables Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
I also am having ground loop issues with my Transporter but NOT due to cable inputs...I don't currently have cable installed. Using a 'cheater' resolves the issue but I assume that is not recommended. Any recommednations? -- mmg_fan mmg_fan's Profile: http://forums.slimdevices.com/member.php?userid=9157 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
mmg_fan wrote: Using a 'cheater' resolves the issue but I assume that is not recommended. Smart call. Cheaters are very much not recommended, and in some places violate the electrical code, which is illegal. Any recommednations? I assume you've done the obvious stuff like plugging all of the electronics into a single electrical outlet. You should do a bit of problem isolation. for example: unplug everything. Plug in just the amp/preamp and transporter. listen. Got loop? Bad, but you know its in those three. No loop? good, add something else, when loop shows up, you know the bad guy. Can you run balanced? The pro-audio world has isolation transformers, not cheap for ones with any prayer of being linear in 20-20kHz -- Pat Farrell http://www.pfarrell.com/ ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
Yes, I seem to recall I get the problem with the amplifier(Jolida hybrid 1501a) plugged in the same time as the Transporter. So does this mean the problem lies with the amplifier? And will 'noise filtering' solve this, as is offered in the mid level Monster 'power bars' , or do I need something more specialized and expensive(ie the aformentioned isolation transformer)? -- mmg_fan mmg_fan's Profile: http://forums.slimdevices.com/member.php?userid=9157 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
mmg_fan wrote: So does this mean the problem lies with the amplifier? ground loops are typically caused by a party, not one. Are you using RCA or XLR? And will 'noise filtering' solve this, as is offered in the mid level Monster 'power bars' , or do I need something more specialized and expensive(ie the aformentioned isolation transformer)? Not likely. A ground loop is caused by unequal ground voltages between two pieces of gear. No filter before the two pieces can do anything. -- Pat Farrell http://www.pfarrell.com/ ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
using XLR for analog out on the Transporter -- mmg_fan mmg_fan's Profile: http://forums.slimdevices.com/member.php?userid=9157 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
would a product like this be sufficient to eliminate ground loop? http://www.stereotimes.com/acc072707.shtml -- mmg_fan mmg_fan's Profile: http://forums.slimdevices.com/member.php?userid=9157 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
mmg_fan wrote: would a product like this be sufficient to eliminate ground loop? http://www.stereotimes.com/acc072707.shtml No it addresses a different problem. You need something to break the loop between your Transporter and the amp/pre Its not much different than a cheap computer power strip. If you have one of those, go ahead and try it, plug the TP and the amp/preamp into a common power strip. -- Pat Farrell http://www.pfarrell.com/ ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
mmg_fan;307011 Wrote: Yes, I seem to recall I get the problem with the amplifier(Jolida hybrid 1501a) plugged in the same time as the Transporter. So does this mean the problem lies with the amplifier? And will 'noise filtering' solve this, as is offered in the mid level Monster 'power bars' , or do I need something more specialized and expensive(ie the aformentioned isolation transformer)? OK let's see. If you have a ground loop with just a TP+amp connected via 2 xlr-xlr cables, then: 1) disconnect each xlr-xlr cable in turn - does the hum go away? 2) if the hum goes away when only one xlr is connected then the other cable is faulty 3) if the hum goes away only with both cables disconnected and the amp and tp are connected to the same mains socket then you should get the amp serviced. -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal...SB3+Stontronics PSU - Altmann JISCO/UPCI - TACT RCS 2.2X with Good Vibrations S/W - MF X-DAC V3/X-PSU/X-10 buffer (Audiocomm full mods)- Linn 5103 - Linn Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Townsend Supertweeters, Kimber Chord cables Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
Timothy/tcutting. I think you're both correct. It's not a low freq component (or I would have heard 50Hz from the sub) and if it's high freq then it must be at a level to pass through the amp get cut off by the speaker cross over filters. The Denon is about 3 above the Rotel...this 3 being made up of supports at the front and 3 3x3 fans at the rear. Even with the fans on, the amp sometimes cuts out. Of course, it could be that I'm going deaf ;) -- chinablues chinablues's Profile: http://forums.slimdevices.com/member.php?userid=7955 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
I've seen faulty amps do this with instabilty causing high frequency oscillation that you can't hear... Thing to do is to get a power meter that measures the current on the mains and see what current is drawn with NO input signal and with speakers connected/not connected - see what differences there are. I'd get the amp checked out. It shouldn't cut out unless you are seriously over-heating it (which sounds unlikely from what you've said) or driving it into clipping (again - it would have to be running flat out for that to make it cut-out regularly). -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal...SB3+Stontronics PSU - Altmann JISCO/UPCI - TACT RCS 2.2X with Good Vibrations S/W - MF X-DAC V3/X-PSU/X-10 buffer (Audiocomm full mods)- Linn 5103 - Linn Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Townsend Supertweeters, Kimber Chord cables Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
Sometimes those old chinese dresses are outdated beyond repair Borrow a relatives 'chinese dress' (http://www.prettyladygirl.com/). Sometimes those old chinese dresses are outdated beyond repair, but then again, sometimes theyre not. If you have an (aunt, mom, cousin, sister) who got married in a strapless sheath that would be perfect, theres no reason you couldnt too, assuming theyre open to loaning it out. You can still make the look your own with the veil, jewelry, shoes, a pretty sash. And youll have that #8220;something borrowed#8221; checked off the list. What about the modern cheongsam? With more exchange with the outside world, todays 'cheongsam' (http://www.prettyladygirl.com/) combines both Chinese and western characteristics, traditional and modern features. There are bold changes and innovations. Whatever it is, cheongsam on one hand can still create an impression of simple and quite charm, elegance and neatness. On the other hand, blended with modern features, they can also show peoples individuality and distinctiveness. No wonder cheongsam enjoys a growing popularity in the international world of high fashion. It is a conventional belief that 'silk clothes' (http://www.prettyladygirl.com/) should invariably be present in the wardrobe of everyone who claims to be a connoisseur, when it comes to clothes. The fascination of silk fabric dates back to the ancient times. Silk production was already present at the earliest stages of development of human civilization, and silk trade was a very important part of the economy in ancient China. It was the place where the first silkworm breeding and silk manufacturing traditions were established. Literature, History and Philosophy have covered, and occasionally love to popular movies, but not limited to, circumstances eyeball, and can 'cheongsam wholesale' (http://www.prettyladygirl.com/) seen from different things. Perhaps, she will learn English,calligraphy, tea ceremony learning, learning flower arranging,yoga. A wide range of hobbies, and accumulation of introversion her soul. Can be with their own inherent temperament is focused woman, a woman is the most flavored woman. On the other hand, Tang chinese jackets have also been blended with western designs to please the diversified tastes of modern Chinese. Jin Yonglin, assistant to the general manager of Gege, a famous Tang 'chinese jacket' (http://www.prettyladygirl.com/) manufacturer in Beijing, said, It is wonderful to name Chinese-style costumes Tang chinese jackets, because Tang Dynasty ( 418 A.D.- 907 A.D.) is the most prosperous period in ancient China and China towns throughout the world are also called Tang streets. -- geekguoji 'chinese jacket' (http://www.prettyladygirl.com/) geekguoji's Profile: http://forums.slimdevices.com/member.php?userid=17677 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
DCtoDaylight;241582 Wrote: An Isolation transformer like the one riffer mentions will fix the problem, but in the meantime Is the TV cable ground connected to your household ground? For example, in my house, the incoming cable goes to a connection block, which has a heavy wire from the cable ground to the same ground line as the fuse panel uses. That will kill any loop to the box down the street. Dave All utility service (power, phone, cable) should use the SAME ground rod, but for a different reason, lightning protection. While it is possible this might hum in audio equipment, the more likely cause leakage from the AC power injected into the cable to power the line amplifiers. The subscriber taps remove most of the 60 Hz AC, but as was pointed out by the previous posters, an RF isolation transformer will fix the problem. -- Timothy Stockman Timothy Stockman's Profile: http://forums.slimdevices.com/member.php?userid=8867 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
I had the same issue solved it the same way, i.e., with an RF isolator in the TV signal cable. Solved, insofar as the audible hum was eliminated. However, I am left with a suspicion that all is not totally fixed. I have a Denon 3805 AVR used as a 'pre-amp/mixer' feeding a Rotal RMB 1095 5 channel amplifier. Speakers are BW 804 805s. My remaining problem is that when playing loudly, the Rotel cuts out due presumeably to overheating. My living space is not that huge so I have this nagging suspicion that there remains some non-audible component that is overheating the amp at high volume levels. I have a sub-woofer that goes down to 20Hz, hear nothing from that, so if there is any remaining ground loop component, I suspect its in the higher non audible range. (the amp has a -3db freq response up to 100kHz way beyond my hearing levels) I'd be interested to know if anyone else has this problem, or any suggestions. Dan -- chinablues chinablues's Profile: http://forums.slimdevices.com/member.php?userid=7955 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
Club1820;242103 Wrote: I also had a NASTY ground loop hum in my system caused by the cable connection. I purchased and installed the jensen transformer and it completely went away. Paid $49.99 for it. Parts Express also sells one for way less but I figured I would go with the one that received the best reviews and it has a money back guarantee. I too had a hum problem with my Transporter due to the cable TV connection. I bought a Calrad RF isolation transformer for $12.00 from Blue Jeans Cable, inserted it in the CATV cable path, and the hum went away. Recommended as a viable alternative to the $49.99 Jensen transformer. http://www.bluejeanscable.com/store/rf/index.htm -- Ron Olsen Ron Olsen's Profile: http://forums.slimdevices.com/member.php?userid=9233 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
riffer;241579 Wrote: All you need is an isolation transformer like the one manufactured by Jensen: http://www.jensen-transformers.com/datashts/vrd1ff.pdf I also had a NASTY ground loop hum in my system caused by the cable connection. I purchased and installed the jensen transformer and it completely went away. Paid $49.99 for it. Parts Express also sells one for way less but I figured I would go with the one that received the best reviews and it has a money back guarantee. -- Club1820 Club1820's Profile: http://forums.slimdevices.com/member.php?userid=10999 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
All you need is an isolation transformer like the one manufactured by Jensen: http://www.jensen-transformers.com/datashts/vrd1ff.pdf -- riffer riffer's Profile: http://forums.slimdevices.com/member.php?userid=13459 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Ground Loop and Transporter
An Isolation transformer like the one riffer mentions will fix the problem, but in the meantime Is the TV cable ground connected to your household ground? For example, in my house, the incoming cable goes to a connection block, which has a heavy wire from the cable ground to the same ground line as the fuse panel uses. That will kill any loop to the box down the street. Dave -- DCtoDaylight DCtoDaylight's Profile: http://forums.slimdevices.com/member.php?userid=7284 View this thread: http://forums.slimdevices.com/showthread.php?t=40112 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
