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OK, so everyone seems to be at a loss to explain how the BGT does what it does because there is no complete circuit formed. However, electrostatics may provide an explanation. An entity with a large excess of negative charge such as the negative plate of a capacitor is packed with excess negative charges, which repel each other. Even without a complete circuit, if the charged entity comes into contact with a neutral object then the negative charges will seek to spread out as far from each other as possible in order to minimize their repulsion; in other words the negative charges will flow into the neutral object anyway to achieve as much distance as possible between them. See the attached physics educational link for more complete explanations.So, are we seeing a charging of the component chassis causing the audible effects of the BGT? It seems logical that a chassis ground with more available electrons packed into it's surface might result in more dynamic, punchy sound than a chassis without such extra electrons.
Thoughts?
Edits: 12/12/15Follow Ups:
My Furman REF20i power conditioner has a 'stiffening' capacitor. To keep the voltage from dipping at transients.
My guess is the battery device is doing the same to some small extent.
Well, I finally tried it out you bunch of lunatics! - on both my monoblocks, noticeable in a decent but subtle way, then on my dac - same thing but now accumulative and not so subtle and starting to render some spatial effects. Then finally a week later on my front end (flac streamer) Logitech Transporter - Now I'm thinking maybe the Transporter has a crappy ground plane because Holy Mother of Jesus, what a difference. The combination of all three is equal to a substantial capacitor upgrade.
Never ever heard my system quite like this before!
I'm running 9v little batteries on the amps, and big 6v lantern batteries on the dac and Transporter, 10,000uf Generic bypassed with Multicap film cap 5uf and a mundorf silver in oil 0.1uf on each.(all in my stash)
Sounds great - lightened the bass a little, used 4700uf at first but then 10,000uf (I think this helped with the bass but will have to compare again later) The BGT has really opened up the midrange and extended the top, but now I have spatial effects like nobodys business, quite incredible! Had given up that hi-fi could ever sound like this thought that was just a pipedream.
Has anyone managed to nail a special combo on the caps? mine are amazing as is but the tilt upwards, I can deal with but would love to be able to fill in the lower end too?
Maybe try the Raspberry Pi, and even my Router next?
Hard Drive
Raspberry Pi
Logitech Transporter
Audio Gd Ref7 Dac (AN dac 4.1x out for repair)
Audio Note P4 Monos
Quad Esl 63's
I'm embarrassed to tell my friends, I'm just going to let them hear this
I have also used big 6v/12v lantern batteries but finally settled with standard 9V battery that is also very compact.
There are no additional benefits with lanterns.
After some experimentation, regarding the capacitors, I have settled with Rubycon electrolytics http://www.ebay.com/itm/1pcs-RUBYCON-16V-47000UF-L-ESR-Motherboard-Capacitor-30X50mm-NEW-m-/170753288169?hash=item27c1b067e9
and WIMA MKP 10 polypropylene capacitors that are very compact and very fast.
Silver wire, from the battery onward is also benefitial, IMHO.
I think it is better to keep it as compact as possible.
All of this led to even greater effect.
Believe Stu's website blog discussed the cap values that worked best.
For digital and video, around 100,000uf plus film bypass, along with silver wire.
Analog; around 30,000uf with film bypass.
The type (brand) of film bypass cap will affect the top end; warm sound signature cap will have less top end.
If I recall correctly,around .22uf was suggested for bypass.
This came up earlier in this thread; the effect of the BGT will be nil with a dead battery.
"Believe Stu's website blog discussed the cap values that worked best"
Please post a link to Unclestus blog, thanks...
http://www.audiodirectionltd.com/
go to his Blog section that is to the right end of the screen...
sorry, under the MORE section is his sub-screen blog...
So I removed them. Just a 47,000uF cap and a 9V battery works best in my system, wwhich already has plenty of high end. I notice a fuller bass/lower midrange and a little more dynamics, but no effect on the treble with this arrangement.
You wrote, "It seems logical that a chassis ground with more available electrons packed into it's surface might result in more dynamic, punchy sound than a chassis without such extra electrons."
Why?
Electrons are charge carriers, and the flow of charge is current. Having more charge carriers available to respond to current demands certainly seems like it would help with dynamics, no?
I don't claim to know what the heck is going on with the BGT, but the gospel says that charge "moves" when it is in a circuit. Ok, so the electrons that can flow to the positive side of the circuit from ground can only exactly equal the electrons that can flow FROM the positive side of the circuit TO ground. Somebody's Law of Conservation must say that better. In this simplistic view (I admit), the electrons sitting at ground potential at any point in time would not move (do no good for the sound) unless they were replaced by electrons flowing to ground potential. If indeed they were there in the first place (see the other guy's comment), they would sit there, and ground would have a net negative charge over and above its negative difference from the positive rail. I don't mean to be antagonistic; I learn something from making myself think about it.
Where is the complete circuit when charges move from a Vandegraff generator to a person on an insulated platform?
The other thing to think about are all the "unseen circuits" in any system, the ones that don't appear on the schematics, formed from all the parasitic capacitances and inductances that litter any real system. They can make complete circuits exist where the schematics say they don't, especially when you talk about transient events.
Also not being argumentative, just looking for a discussion.
I do enjoy the discussion, too. Do you perceive that any such "unseen circuits" are at work in the BGT? Anyway, you previously posited a pool of electrons sitting at ground potential as a consequence of their being no circuit with respect to the BGT and the component being affected by the BGT. This is what I responded to. Can you have it both ways? (Typical logical argument says no you can't, but my knowledge base is weak when it comes to electronics and certainly to quantum mechanics.) It seems that if there were an unseen circuit between the BGT and the component, then those electrons would not sit around in excess at ground potential.
I'm trying to stimulate discussion of the various possibilities, not trying to have it both ways. I haven't decided which if any of these I believe.
Is the BGT interacting with/charging hidden parasitic circuits?
Is the BGT a steady state subcircuit that resonates with the AC of the music signal to cause perception of enhanced dynamics?
Does the BGT somehow pump electrons into the ground plane, more than would normally be present, allowing the circuit to react to transients more quickly?
Is there no effect at all and all of us who hear something are suffering from expectation bias?
I made a bunch of the newest versions for the stereo and TV and, on a lark, gave one to a co-worker who plays electric guitar. He plugged the BGT into a parallel input of his amp and, over the space of several days, tried a number of different guitars. His main comments were that it seemed the amp picked up more drive with added detail and that the midrange, always being a little weak, was suddenly filled in. (Like an EQ shaped like a smile is now a flat line.) He even forgot it was plugged in one time and wondered why his axe sounded different. And he likes the change in sound - or at least, I haven't gotten the BGT back after about 2 months!
Now, here's the clinker: the BGT did this on all of his guitars but one and with that one he could not tell any sound difference, with or without. I had built up a pet theory that it was acting on the equipment it was plugged into, but if it shows no difference on one sample, the BGT is not filling in a deficiency of the guitar amp but would seem to be heading upstream to influence either the signal or the guitar producing that sound. And what is it that makes that one guitar immune, so to speak?
Others are free to ponder and suggest ideas; I find the whole thing fascinating, even though I haven't a concrete clue how it works - but it does. On some things.
Interesting. Same thing I hear - fuller mid-bass and more impactful bass.
Now if we can only figure out why...
My favorite physicist Richard Feneyman once said if anybody tells you the understand electricity they are lying. This from the creator of quantum electrodynamics, a theory that has been proved by experiment over and over again
Alan
I thought that the static charge on the chassis might act as a Farraday cage and create a field that repels RFI.
A normal grounded chassis is already a Faraday cage if it completely encloses the electronics, is thicker then the skin depth of the RF and doesn't have large openings relative to the RF frequency. Not sure that the BGT would change that.
Max, I think the situation where you have, say, a charged ball and connect to ground, then electrons can move from the ball to earth. (This basically happens because the ball is charged with respect to earth).
But in a charged capacitor, whether a battery is connected or not, the situation is different. The negative pole of the capacitor has an excess of electrons, sure, but they are being held there by the 'positive charge' (to simplify things) on the other plate. In other words, a charged cap, connected to nothing (or a battery) is in equilibrium.
If you connect the - to earth then nothing will flow into the earth - if any current (ie electrons) *did* flow then this would disturb the equilibrium on the cap, which would immediately suck the electrons back to the plate. (Which is precisely why they won't flow).
Good points and I believe I did mention the effect of the positive plate in pulling the charge back, somewhere in this thread. Perhaps, though, just disturbing the equilibrium temporarily is enough. Remember that the ground is part of the AC (music) circuit, and the music signal is continually "disturbing the equilibrium". Could it be that the disturbance of the equilibrium with the 9V of potential pulling it back to equilibrium is what we perceive as enhanced dynamics? In other words a dynamic resonance effect?
Edits: 12/14/15
No, as I explained, there is no reason for the equilibrium to be disturbed so it won't be.
A fluctuating AC voltage connected to the negative plate is certainly a reason for equilibrium to be disturbed. Equilibrium is simply a mental construct to represent the time-averaged behavior; in reality things are much more dynamic than that.
https://en.wikipedia.org/wiki/List_of_types_of_equilibrium
I don't see equilibrium as merely a mental construct - it has clear meaning in physics. And this thread started out being about the physics.
So, I disagree, but won't argue any more.
Rather at best it achieves steady state conditions, as there is always a leakage current flowing. Steady state is only steady until the system changes in some way. Connecting a fluctuating audio ground qualifies as a change to the system, no?
According to the link here, when the negative of a charged cap is connected to ground, some charge is expected to redistribute itself into the ground, since attaching the ground changes the system (it adds the large equipment chassis surface area to the negative plate and also connects the plate to the stray capacitances in the system), even though there is not a complete circuit formed. So a continuous current will not flow but charge may indeed redistribute itself to the equipment chassis and ground, especially if there is a dynamic perturbation of the ground (such as a music signal?). This will be limited because the attractive force of the positive plate to the electrons on the negative plate will eventually balance out the repulsive forces pushing the electrons out of the negative plate.Enough to affect the sound? Perhaps. It seems plausible.
Edits: 12/13/15 12/13/15
My thoughts on the matter are that the battery and circuit are an antenna, picking up on the ever increasing array of electromagnetic noise that's in the air.The sound is modulating on top of the noise, making a change that can be perceived. The effect of the charge from the battery would be much smaller and swamped by the noise.
A practical test would be to use a dead battery and see what happens.
Regards,
-reub
Edits: 12/13/15
If you can reliably hear a difference, then why bother theorizing? Conduct experiments to see what matters and what doesn't. The suggestion of a dead battery is a good start. On the other hand, if you can't conduct these experiments because you can't reliably hear a difference then why bother trying to explain the tweak?
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Edits: 12/17/15
That's a possibility, and one I thought of way back when I first read about this. Actually, that's why it took me this long to try it. I can't however reconcile RF pickup with the bass impact and dynamics I heard once I tried it; to my experience RF pickup results in harshness in the high frequencies, which is quite the opposite of what I've heard with a battery and big electrolytic - it actually sounds a bit warmer and more punchy with the BGT in my system.Interestingly, the effect of a bypass cap across the big electrolytic is readily heard as a tilt to the upper frequencies which I find unpleasant. I've tried a 4.7uF Solen and a 470uF Oscon and liked neither.
Thanks for your input!
Edits: 12/13/15
Having the chassis grounded, as most equipment does, would seem to pose a challenge to the electrostatic model here, since excess charge should continue to spread out as long as there is a conductive path to a more neutral body, such as earth. However, all real-world ground connections have resistance and inductance which impede the flow of negative charge from the ground into the circuit. So, perhaps the effect we see is a dynamic one, wherein the BGT supplies negative charge to the chassis in the brief moments where the attached circuit draws sudden pulses and the ground is unable to instantaneously provide the needed charge due to its inherent impedance. There would then be a momentary depletion of negative charge in the ground, and the excess charge in the BGT could then spread out into the ground, supplying the circuit for that brief period.
Anyone care to comment?
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