ML's With Audio Prism Ground Control

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As they say Bernard, some things are worth the wait.

Cheers, Greg
 
You pay only $750 rent for your ranch ? I'm moving to Indy ! :cool:

There you go everything is relative, I thought $750 a day was a lot of money, but obviously in the Great White North it is a deal.:D
 
I had thought about the reference ground control, but held off after reading that you may have the soundstage shrink in size a bit but get better detail retrival with the reference models over the standard ground control. I found the soundstage increased in every which way with the standard units along with all the other benefits.

I am totally impressed with the standard units.I have never heard my Martin Logans sound this good before. There is a review by user Ozzy in the Audiogon thread I have attached at the bottom of this post. It's an interesting read. Let us know how the reference models sound in your system.Bud Purvine said in some systems the reference will close down the soundstage slightly, althouh in his system he has 2 reference GC's on the speakers and a standard set on the amp. I would suggest anyone interested to read the whole audiogon thread.

Remember, if you have any questions, Bud Purvine , the inventer of ground control will be more than happy to answer them on the provided audiogon link.http://forum.audiogon.com/cgi-bin/fr.pl?htech&1265474015&&&/Did-anyone-experience-Audio-Prism-s-Grou

Ozzy's audiogon ground control review of both standard and reference http://forum.audiogon.com/cgi-bin/frr.pl?raccs&1280171827&&&/AudioPrism-Ground-Control-Tweak

Cheers,Greg

Since I am putting them in to the 5.1 surround sound system, soundstage is not an issue, but we shall see.
 
There you go everything is relative, I thought $750 a day was a lot of money, but obviously in the Great White North it is a deal.:D
My sympathies - I did not realize that you were living from day to day :(........................:D
 
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Interesting that the Six Moons guy couldn't hear any difference. They are the kings of snake oil tweeks, so now I'm really skeptical. Going to have to get a pair to cut em open and see what's inside.

The Transparent and MIT cables use somewhat of an RC network to (according to them) optimize the impedance match between amp and speaker, so in some cases they can work, depending on the amp and speaker involved.

But I'm really curious how just attaching a piece of wire or even a network to just one post of your speaker can have any effect. The guys at MD are dying for me to try these, so looks like it's time to jump in.
 
Got a notice from MD that these finally shipped. They should be at the house tonight.

I got enough to do CLXs and Stage. What I thought I would try would be to play Beatles Love without Prisms and then immediately attach them and play Beatles Love again. Hopefully there is a nice effect, if not I will be sending them back or selling them here at MLC:D
 
Do please spend about 4 hours with them. You should hear a difference in some qualities of playback within one minute, but it does take a few hours for the things to fully charge and provide all they are going to provide.
 
Do please spend about 4 hours with them. You should hear a difference in some qualities of playback within one minute, but it does take a few hours for the things to fully charge and provide all they are going to provide.
What is there to be charged ?
 
There is a small triboelectric effect that helps to accumulate the electrons that jitter into these things. Causes more of the vacant orbits to become useful for the support of ever smaller signal events. The charge buildup between wire and dielectric additions are what needs to be charged.

The GC are there only for the back half of the wave form, what has already passed through the load and thereby becomes susceptible to all of the dielectrics and metal to metal contacts between your system and wherever lowest ground potential happens to be in your system. Thus GC acts as a very low RAC and RDC unterminated wave guide, with significant momentary storage and because of this provides signal with a choice of wave guides.

At least, this is the current postulate.

For tonepup, just look again at the six moons review. They have already cut one apart, to see what spills out. What you see there is all there is, no beryllia, no crystals, no dirt. If you want to read a huge argument about their usefulness go here. A pretty excellent peer review.
http://www.diyaudio.com/forums/showthread.php?postid=1213239#post1213239

Bud
 
Jeff,

If you take a look at the 6 moons review again, Steve Marsh is the 2nd reviewer and said he wouldn't want to go without them after having them in his system. Read the second review.There are many other positive reviews, Stereo Times, etc

How Stephen , the 1st reviewer couldn't hear a difference is beyond me. It is quite apparent. I am getting ready to order my other sets for the bass and amp very shortly. I would agree with Bud that the effects are noticible right away but do improve with a little more time on them.

If you want to hear your ML stators as never before, these are the ticket!!
 
Well I listened to the Ground Control Prisms tonight.

They don't seem to do any harm, and I think there are some neat effects but I only had a half hour to test them so I will have to work on it some more in the coming days.

I am using the Refence GC Prisms, and I only listened to Beatles Love DVD Audio so I will have to pick some more of my reference pieces and see what happens.

Color me undecided until then:D
 
I've talked to three friends of mine that design audio gear and they've all said this is snake oil, but I've ordered a pair in the interest of investigation.
 
There is a small triboelectric effect that helps to accumulate the electrons that jitter into these things. Causes more of the vacant orbits to become useful for the support of ever smaller signal events. The charge buildup between wire and dielectric additions are what needs to be charged.

The GC are there only for the back half of the wave form, what has already passed through the load and thereby becomes susceptible to all of the dielectrics and metal to metal contacts between your system and wherever lowest ground potential happens to be in your system. Thus GC acts as a very low RAC and RDC unterminated wave guide, with significant momentary storage and because of this provides signal with a choice of wave guides.

At least, this is the current postulate.
I am having a tremendous amount of difficulty understanding your explanation, but what puzzles me even more is your last sentence, "At least, this is the current postulate", which implies that the explanation may in fact be proven wrong at a later date.
 
Bernard,

"What is there to be charged ? "


You mean besides your credit card.........just kidding Bud.

These things are kind of interesting. It seems that the Ground Control is charged with electrons as the current goes through it.

Now I am not sure what that means, but on purpose I did not review the Ground Control stuff, just so I would not be influenced as to what to listen for. I did not read anything about them other than what Moon said at the beginning of this thread and that was read so many moons:D ago that I did not remember what I was suppose to listen for.

I went in to the test session literally blind or maybe deaf. I listened to the beginning of Beatles Love and there is a lot going on there, bees and birds, and outdoors ambiance as well as all four Beatles singing. My goal was to see if I could hear a difference, any difference. And the first thing that popped in to my mind is that there definitely seemed to be more air around each type of sound. There was more separation when multiple voices or sounds were generated at the same time. There was less of a hard edge and more of a natural flow..................And then the wife yelled downstairs and said for me to turn it down so Projector upstairs wouldn't shake and mess up her favorite TV show Top Gear..........okay it was Dancing with the Stars, but you gotta admit Top Gear sounds better.:D

Anyway after a half-hour I decided the Ground Control definitely does not do any harm and if I can replicate this air around intruments, voices and sounds on my other reference discs, well then the Audio Prism Ground Controls are staying and I will probably look into adding them to the preamp, amp, Disc player, turntable, DAC, sub, vibrator.........wait how did that get down here.

Anyway, this is definitely fun using Ground Control, although I can't figure out how to hook one up to the vibrator cause I am thinking........:D
 
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There is a small triboelectric effect that helps to accumulate the electrons that jitter into these things. Causes more of the vacant orbits to become useful for the support of ever smaller signal events. The charge buildup between wire and dielectric additions are what needs to be charged.

The GC are there only for the back half of the wave form, what has already passed through the load and thereby becomes susceptible to all of the dielectrics and metal to metal contacts between your system and wherever lowest ground potential happens to be in your system. Thus GC acts as a very low RAC and RDC unterminated wave guide, with significant momentary storage and because of this provides signal with a choice of wave guides.

At least, this is the current postulate.

For tonepup, just look again at the six moons review. They have already cut one apart, to see what spills out. What you see there is all there is, no beryllia, no crystals, no dirt. If you want to read a huge argument about their usefulness go here. A pretty excellent peer review.
http://www.diyaudio.com/forums/showthread.php?postid=1213239#post1213239

Bud

Bud,

I am going to keep an open mind and see what the the others have to say.

BUT I am an avid SF reader and fan; your explanation is top notch SF material. :D
 
Just ordered 4 RCA Ground Controls, they will be here tomorrow.

I will put them on the equipment and see what happens there.
 
I've talked to three friends of mine that design audio gear and they've all said this is snake oil, but I've ordered a pair in the interest of investigation.
Jeff, I too think this is snake oil, but can't discount what Greg is hearing.
 
BUT I am an avid SF reader and fan; your explanation is top notch SF material.

Couldn't agree more. If there was a well documented, straight forward, first approximation derivation that covered the audible results, I would be MORE than happy to utilize it.

These GC's come from investigations into speaker cables, as I was zeroing in on what I needed to do to audio transformers to obtain more performance from them. I am shoving the Q pretty hard with the transformers and different speaker cables, when listened to through full range drivers with EnABL eliminating the effects of non minimum phase behavior, were noticeably colored in a number of different ways. I ended up developing my own neutral cables that, at least to my ears and those of a number of others, were not really audible, from 6 inches long to 9 feet.

What I learned about different dielectric materials, the audible effects from their characteristics, especially on the return cable set, and wave guides led me to wonder about grounds. Reading Ralph Morrison's book on grounding and shielding led me to experiment with poured ground planes in a pre amp I was building up. Changing from a solid core to a massively multi stranded wire, from a smaller than optimal poured ground, to IEC ground pin, introduced me to some things that truly did seem like Sci Fi.

The GC's are just an extension from that, one of those "hmmmm I wonder what would happen if you did that" moments. Audio Prism's owner, Byron Collett got a pair of early models and here we are today.

Things we have learned, in a general sense, are:

If you need stage width, but have a satisfactory amount of information, use the Standars GC lugs on your speakers.

If you then need more information (air, space and note specific internals) then add a pair of Reference GC's to your amp, on the out put speaker lugs, minus terminals.

If you have harshness or grain in SS equipment, start adding RCA GC's, with the standard RCA's first. Most equipment seems to work best with one of each, a standard and a reference, assuming a common ground connection between channels and input and output plugs. The RCA's can go in either under those circumstances.
 
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