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Discussion Starter · #1 ·
Remember that old David Bowie song which goes "Major Tom to Ground Control"?

http://www.musicdirect.com/product/8...mpaign=sb_405h


Now we've got a "Ground Control" for home theater.


I recall Granite Audio's "Ground Zero" which provided a substitute for real star grounding between your comonents. It works. And a demo using test equipment showed this.


But this new "Ground Control" doesn't connect to anything but I guess the speaker binding posts.


Amir, what are your thoughts?
 

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This is post-modern art.


Really really REALLY subtle but still amazing post-modern art.


That's the only way I can handle this without subjecting myself to involuntary self-defenestration.
 

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It will go well with my Tice clock...
 

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Quote:
Originally Posted by Steve Bruzonsky /forum/post/18258211


Amir, what are your thoughts?

I can't think as I am having one of those "electrostatic moments."



Seriously, where does the other end go? Just dangling in the air?
 

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Discussion Starter · #6 ·

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Originally Posted by amirm /forum/post/18260558


I can't think as I am having one of those "electrostatic moments."



Seriously, where does the other end go? Just dangling in the air?

Thats what kills me about [email protected]@@


Granite Audio's Ground Zero actually substitutes as if you had star grounding, and doesn't hang in the air:

http://www.graniteaudio.com/zero/index.html
 

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Steve. Obviously hanging wires terminated with something or orther cannot replace using star grounds in lower level electronic circuits. . What I suspect is going onis the device being hung on the speaker binding posts is sinking some of the backwave reflections which otherwise would travel back to the amp and be sunk on chassis ground and ultimately be grounded to the 120V electrical supply for the amplification system.This might indeed have the same audible effects of a star ground but would in no way obviate the need for proper grounding design of an amp or preamp. At the risk of being rediculed here I do suspect that the devices under discussion would result in significant audible improvements. The concept was validated some years ago by Tara Labs which used an ungrounded conductor going from the positive speaker binding post. Some here might experiment by simply hooking up a length of wire from each positive post and leaving the other end unconnected. We found that doing the same for the negative didn`t help much but it might have resulted in a slight improvement. One must remember that often there is a significant impedence mismatch between the amplifier output and the speaker input. This will indeed cause reflections and getting rid of them by sinking them somewhere before thay travel back to the amps output stage will improve the sound. Particularly at low levels because no matter how good the design such audio AC will not be entirely isolated from the amplifier circuit and will be measurable as low level modulations. Low level grunge.
 

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Discussion Starter · #9 ·

Quote:
Originally Posted by mark haflich /forum/post/18260920


Steve. Obviously hanging wires terminated with something or orther cannot replace using star grounds in lower level electronic circuits. . What I suspect is going onis the device being hung on the speaker binding posts is sinking some of the backwave reflections which otherwise would travel back to the amp and be sunk on chassis ground and ultimately be grounded to the 120V electrical supply for the amplification system.This might indeed have the same audible effects of a star ground but would in no way obviate the need for proper grounding design of an amp or preamp. At the risk of being rediculed here I do suspect that the devices under discussion would result in significant audible improvements. The concept was validated some years ago by Tara Labs which used an ungrounded conductor going from the positive speaker binding post. Some here might experiment by simply hooking up a length of wire from each positive post and leaving the other end unconnected. We found that doing the same for the negative didn`t help much but it might have resulted in a slight improvement. One must remember that often there is a significant impedence mismatch between the amplifier output and the speaker input. This will indeed cause reflections and getting rid of them by sinking them somewhere before thay travel back to the amps output stage will improve the sound. Particularly at low levels because no matter how good the design such audio AC will not be entirely isolated from the amplifier circuit and will be measurable as low level modulations. Low level grunge.

Mark, good explanation. Interesting. But wouldn't using a product like Granite Audio's Ground Zero, where these thingamagics connect to the star ground rather than float "in the air", even be objectively and subjectively (to those of us who listen,not to those of us still in college with boom boxes like our friend HD_Newbie) better?
 

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Steve.I really don`t know.i belive the idea behind usinga star ground is to eliminate slightly different ground potentials in an electronic circuit. Varying ground potentials can cause a low level signal riding at a lower potential than the signal desired to be amplified by the amplifier circuit.These robs the ampof some of its intended power and can be measured if not heard. What the Granite module does or evenwhat itis,Ihave noidea.But measurements could be made before or after itsadditiontothe circuit and I assume audiophiles could hear the difference as a cleaner more punghy or dynamic sound.
 

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"Backwave reflections"? If we assume the speaker line is pretty lossy and slow so maybe the wave travels at only 0.7c, then at 100 kHz (far above audible but bear with me) a wavelength is 0.7 * 3e8 / 100e3 = 2100 m. A quarter wavelength, which could cause signal inversion if the amp and load were completely opposite impedances (short vs. open), is 525 m (1,722.4 feet). You'd have to have some pretty long lines for reflections to be a significant problem even assuming the amp itself didn't have low enough output impedance to deal with them. I suppose you could argue it acts as a stub filter for some particular RF frequency known to wreak havoc on all things audio, but...


A star ground will help equalize the system ground potential, but the main thing it's good for is breaking up ground loops and preventing different signals from mixing. A signal always has a return; positive and negative current flow in a pair of wires (or planes, etc.) A star ground gives signal currents a place to "dump" instead of (potentially) routing around and mixing with some other signals' returns (leading to distortion and perhaps instability).


Whatever - Don
 

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Discussion Starter · #12 ·

Quote:
Originally Posted by mark haflich /forum/post/18263814


Steve.I really don`t know.i belive the idea behind usinga star ground is to eliminate slightly different ground potentials in an electronic circuit. Varying ground potentials can cause a low level signal riding at a lower potential than the signal desired to be amplified by the amplifier circuit.These robs the ampof some of its intended power and can be measured if not heard. What the Granite module does or evenwhat itis,Ihave noidea.But measurements could be made before or after itsadditiontothe circuit and I assume audiophiles could hear the difference as a cleaner more punghy or dynamic sound.

Mark, when Granite Audio first came out with the Ground Zero, its proprietor Don Hoglund came over with a Ground Zero AND test gear.

I then had five Bryston 7B monoblocks (now Theta Enterprise monoblocks). Don measured the noise objectively I believe coming out of the amps, with the Ground Zero engaged and disengaged. Objectively using the Ground Zero was about t 3 dB improvement. I had the amp ground lifts not engaged. When we engaged the ground lifts, the Ground Zero no longer made a significant objective improvement. I elected not to use a Ground Zero and the extra cabling and simply engaged the ground lift switches with the Bryston amps.
 

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Don. I don`t quarrel with your theory but try a piece of solid copper wire attached only to the positive connector on your speakers the same approxiate length as yours peaker wire and tell us if you hear an improvement at low kevels.
 

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Quote:
Originally Posted by mark haflich /forum/post/18264147


Don. I don`t quarrel with your theory but try a piece of solid copper wire attached only to the positive connector on your speakers the same approxiate length as yours peaker wire and tell us if you hear an improvement at low kevels.

Hi Mark,


Seems like it would act more like an antenna for hum and noise, but I could try, I suppose. Does it have to be solid, or will stranded do? Should it be routed along with the speaker lines or elsewhere? And, why so long, especially since the item in question appears to be rather short (6 inches or so)? Do you have a theory on why it would improve things?


I am willing to be proven wrong (have in the past and shall in the future), but I'd like some rational for why such a thing would help.


Thanks - Don (ever curious)
 

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Don. My expeprience was with pieces of Tara labs wire long ago. My store used to terminate it and the termination was with a number of wires surrounded by some sort ofouter sheeting which if I remember correctly, one wire in the positive run not being terminated or connected at the positive amp end. If I remember, the wire conductors were solid but I just dont remember. The unterminated wire was bundled in the wrap and was the same length less a 1\\4 inch or so. I don`t know what the termination is in the device Steve brings to subject in this thread.
 
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