[dvw]

Quote:

Originally Posted by sejarzo /img/forum/go_quote.gif I'm an engineer who often must read technical docs for work that are not in my precise discipline or area of expertise. Without question, I've rarely read no other docs that presume little or no tech knowledge and within a few pages have conveyed so much so clearly as the papers on the Rane site.

Especially fig.4 and fig.5

 

[10068]

Quote:

Originally Posted by sejarzo /img/forum/go_quote.gif I'm an engineer who often must read technical docs for work that are not in my precise discipline or area of expertise. Without question, I've rarely read no other docs that presume little or no tech knowledge and within a few pages have conveyed so much so clearly as the papers on the Rane site.

What this sarcasm or said in seriousness? I can't tell

 

[sejarzo]

Quote:

Originally Posted by Sduibek /img/forum/go_quote.gif What this sarcasm or said in seriousness? I can't tell

Definitely serious. Their documents are very helpful in understanding the differences between pro and consumer gear. Given that line is becoming more and more blurry, with the popularity of the Benchmark DAC-1, Apogee Mini-DAC, Lavry DA-10, down to the PreSonus Central Station and E-MU 0404 USB here, anyone considering using a pro audio device for consumer listening would do well to poke around that site and learn a few things.

I just realized that I typed a word in error in that post...I meant to write that I rarely read any other docs that were as good as the Rane info, not "rarely read no other docs".

 

[earwicker7]

Quote:

Originally Posted by dvw /img/forum/go_quote.gif However, in your case, I speculate that you must be using a balanced input from the Linn to the B-52. The balanced input presents a 600 ohm input impedance and which might pick up just enough noise after amplification to be audible. Balanced connection are good in taking out differential noise but not common mode noise (the noise from the ground). The Linn actually has a chasis ground in the back for you to connect to a ground for this specific purpose (kind of like the ground pin for your phono player).

Bingo!

I'm really curious about something now... to all of the people with the dead silence on your systems, are you using a fully balanced system? Everything in my system is balanced.

 

[JohnFerrier]

Balanced v non-balanced; or, tube v solid state? Balanced may have slightly lower (common mode) noise. However, tubes have higher (even harmonic) distortion and noise (than solid state). Some people like the "euphoric coloration." Which is what "tube rolling" is about.


.

 

[Sovkiller]

Quote:

Originally Posted by earwicker7 /img/forum/go_quote.gif Bingo! I'm really curious about something now... to all of the people with the dead silence on your systems, are you using a fully balanced system? Everything in my system is balanced.

Nope mine is completelly single ended...

BTW, not sure about that Linn you are using, I'm not familiar with the Linn line at all, but the one Nik has, according to them, they reco to use SE outputs over the balanced ones, as they are better than the balanced, it seems that what they use is an internal splitter to convert the SE signal from the DAC into balanced, so you have far more parts degrading the signal in that connection over the simple straight through SE...the balanced operation most of the times in those players are just to add versatility, in case you have balanced gear, and have to use it, but they are not fully balanced from the DAC out, so using balanced output on those sometimes is worst than the SE...

 

[Uncle Erik]

I came across this article on practical solutions to killing buzz/hum in audio. He discusses balanced applications, as well, so it might be useful here.

Kill Studio Hum and Buzz at the Source

 

[sejarzo]

Quote:

Originally Posted by earwicker7 /img/forum/go_quote.gif Bingo! I'm really curious about something now... to all of the people with the dead silence on your systems, are you using a fully balanced system? Everything in my system is balanced.

You need to re-read my response to dvw's post that you quoted and my response to that. He effectively retracted the comment that you reference.

Balanced systems, connected and working properly, have lower noise than single-ended systems. That, my friend, is the only reason that balanced systems were invented--to reduce noise.

Also, it is good to note Sovkiller's response. One noted recording engineer who moderates a home recording forum says that in his studio, properly designed and wired, he uses single-ended connections whereever possible. Why? The internal signal path in a lot of recording gear is natively single-ended. In such units, there are bal-to-unbal circuits on the inputs and unbal-to-bal circuits on the outputs that exist solely to interface the units with other balanced gear. He says the extra circuitry contributes unnecessary noise and distortion, so why bother if you don't need to use balanced connections to reduce noise from interference?

On the other hand, most DAC chips put out a differential signal, and often use a circuit that combines conversion to single-ended with the required filtering between the output of the chip and the analog outputs. Sometimes players/DAC's that have balanced outputs feed the output from the DAC chip itself to true balanced output circuits designed to drive balanced lines, and a parallel circuit then derives the single-ended output from the balanced outputs. One would need a schematic to be sure of what is in any particular unit with both types of output.

 

[rsaavedra]

I´ll only post a link to an analogy submitted not too long ago:

Analogy between power cord before a regulated power supply, and a water pipe before a regulated boiler system.

 

[sejarzo]

Excellent analogy.....I've often wondered how adding anything claimed to be additional filtration upstream of a properly designed PSU should have anything to do with noise at the other end of the device.

 

[dvw]

Quote:

Originally Posted by sejarzo /img/forum/go_quote.gif You need to re-read my response to dvw's post that you quoted and my response to that. He effectively retracted the comment that you reference.

As I said before, I was less than precise, what I really mean to say in in this link.

http://users.ece.gatech.edu/~mleach/ece4391/noise_a.pdf

Zs is directly proportional to noise pickup. In this case output impedance of the Linn. The reference is only a single ended model. But I think is good enough to show the effect of Zs. If Zs is close to zero, the noise will be limited. In the case of Linn, Zs will be half in a single ended configuration.

In a balance system, there is more than one ground. An improper connection will create more noise. The most precise description is in fig. 4 and 5 of the Rane reference. For the Linn, in the back of the player there is a connector for signal ground.

I hoped this is a clearer post than my last one.

 

[sejarzo]

Quote:

Originally Posted by dvw /img/forum/go_quote.gif In a balance system, there is more than one ground. An improper connection will create more noise. The most precise description is in fig. 4 and 5 of the Rane reference. For the Linn, in the back of the player there is a connector for signal ground.

Sure, there are both chassis ground and signal ground, but as noted in the Rane info, they are generally connected at a single point somewhere inside the unit. It is important to note that Figure 4 shows what would be ideal, but most gear isn't built that way; pin 1 on most XLR outputs seems to be tied to signal ground, not chassis ground.

The connection on the back of the Linn appears to be directly to chassis ground, not signal ground, because it doesn't appear to be insulated from the chassis. As far as I know, if a piece of gear uses a three-conductor power cable, then the case/chassis is generally tied to the earth/ground pin on that cable.

In fact, this is what the Linn manual states re that connector:

"EARTH GROUND For connecting the unit to an earthing terminal if no mains earth is available"

That implies it's not meant at all to be used as a signal ground.

All of that leads me to believe that pin 1 of the XLR in the Linn is connected to signal ground--the typical situation.

 

[dvw]

Quote:

Originally Posted by sejarzo /img/forum/go_quote.gif Sure, there are both chassis ground and signal ground, but as noted in the Rane info, they are generally connected at a single point somewhere inside the unit. It is important to note that Figure 4 shows what would be ideal, but most gear isn't built that way; pin 1 on most XLR outputs seems to be tied to signal ground, not chassis ground. The connection on the back of the Linn appears to be directly to chassis ground, not signal ground, because it doesn't appear to be insulated from the chassis. As far as I know, if a piece of gear uses a three-conductor power cable, then the case/chassis is generally tied to the earth/ground pin on that cable. In fact, this is what the Linn manual states re that connector: "EARTH GROUND For connecting the unit to an earthing terminal if no mains earth is available" That implies it's not meant at all to be used as a signal ground. All of that leads me to believe that pin 1 of the XLR in the Linn is connected to signal ground--the typical situation.

If all connections are connected correctly, then the amp should be dead quiet. If the noise is picked up from the source, how would a power cord make a different. My only theory is that somehow the Shunyata ground has create a ground reference that corrected a typical balanced system connection error.

The bottom line is whatever the reason is. I'm pretty sure it's measurable and traceable.

 

[AudioCats]

Does anybody know what kind of "sand" was used to stuff the garden hose?

 

[spritzer]

Quote:

Originally Posted by AudioCats /img/forum/go_quote.gif Does anybody know what kind of "sand" was used to stuff the garden hose?

I have some older Power 3's and they had some ferrite powder in them. It's magnetic that's for sure so it isn't sand.