Sure, but you can't really use a single random (or hand-picked) example with arbitrary values as evidence of a general statement.
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This audio cable business is getting out of hand...
- Thread starter amirm
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Sure, but you can't really use a single random (or hand-picked) example with arbitrary values as evidence of a general statement.
digicidal
Major Contributor
The question I have, which I've seen about as much data from table designers/producers as I've seen from cable manufacturers (hence my comparison here) is how effective proportionally the table itself is at resolving them. Secondarily I would add, how proportionally detrimental they actually are. Obviously when dragging a stone through delicate vinyl, lateral motion and vibrations are potentially damaging and possibly audible contributors to the sound - although I question the extent which it appears you would place as "highly" and I would place "slightly".
Comparing, for example, the Clearaudio Performance DC (~$5000) to an Audio Technica LP1240 (~$500) - would you say the former is 10% better at damping vibrations, maintaining constant speed, etc? 5%? 1%? I totally agree that there are a number of physical and environmental factors which higher-end tables seek to better overcome... I just question whether or not the average enthusiast could tell the difference blinded (provided that the same cartridge, phono stage, platform/shelf, location, etc. was the same).
I tend to (naively perhaps) equate most of those problems with jitter in the digital domain. Sure it has a measurably deleterious effect on sound... but only when it reaches some pretty high levels and easily audible only under a few conditions before that.
Is it something to strive to reduce as much as possible? Sure. Is it worth paying thousands extra for in order to have the absolute lowest possible levels? Not at all. Maybe my 99% digital life now (haven't been "majority vinyl" since about 1986) is clouding my perspective. But I remember quite enjoying listening to LPs on some really horrible tables back then... and similarly enjoying them on a friend's father's "high-end rig" as well. Naturally I didn't do an A-B between the two... but I was perfectly happy with either. And that was factoring in the massive difference between KHorns (his) and Panasonic box speakers from Sears (mine) - not to mention the rest of the systems.
We are so off-topic here, I know that, but I don't want people here to actually think that your scenario is something normal. No way to have such a high grounding resistance in a home! Better connect Earth to Neutral than having a 100 Ohms resistance on the Earth; after all, they're already connected together down the street anyway.
I'm also posting my home earthing resistance; it was taken after 3 weeks from the last rain, so it quite acceptable.
Five Ohms is the maximum allowed Earthing resistance at the main entrance (in front of the electricity panel)! Also, the inner wiring will add less than 0.5 Ohms from one end to the other of house circuitry. Please read http://www.esgroundingsolutions.com/what-is-an-acceptable-earth-ground-resistance-value-5-ohm-or-25-ohm/#:~:targetText=In%20the%20USA%20NEC%20it,is%20on%20the%20high%20side and https://www.engineeringtoolbox.com/copper-aluminum-conductor-resistance-d_1877.html.
Whoever has a higher Earth resistance higher than 5 Ohms should definitely call the Electrician guy.
P.S.: And let's start using RCBO. Italian people call this "Salva Vita", so there must be a good reason for that.
Zog
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I have not heard either of the tables you mention. Though I did have a Marantz TT that was a clone of the Clearaudio Emotion - close to the Performance DC - perhaps a second cousin. No double blind test but 'upgrading' to a cheaper direct drive resulted in an improvement. Hard to put into words but a sense of solidity. I'll take this opportunity to plug one of my pet theories - namely that the best judge of gear is the lone audiophile. He has his listening room and his gear and he is intimately familiar with the sound. When you have been listening for a year or more to the same stuff you are uniquely qualified to detect differences.
Back to price, I think most agree that there is (1) some correlation between price and performance; and (2) diminishing returns. What I say is that the correlation is a very loose one. I mentioned the TTs. Another is my recent upgrade to to the Matrix Audio X-Sabre DAC. The Matrix is better that my previous W4S DAC but a lot cheaper. Actually this sort of thing is but one example of the service that this forum provides to the audiophile community.
blackmetalboon
Active Member
That is a slightly different issue. We don't really care about the earth rod - that is there to deal with static electricity / lightning. What we care about is resistance to the electrical neutral/common.
blackmetalboon
Active Member
In the UK one of the various earthing arrangements uses an earth rod as a means of earthing the electrical installation.
Sure, but as I wrote, that is for lighting protection and static electricity. There is a separate neutral/earth return all the way to your transformer/distribution station. In any case it doesn't matter for audio - as long as there is a common "neutral" point, the absolute potential of it doesn't matter. Voltage is the potential difference between two points, not the potential between a point and some universal reference.
blackmetalboon
Active Member
Look up TT Earthing Arrangement.
Speedskater
Major Contributor
Isolated ground rods are dangerous and illegal !!!!
All ground rods serving a building need to be bonded together.
Yes that is the connection that matters.
But 25 Ohms is way lower than most residences. It takes many rods in most locations to come close to that.
Speedskater
Major Contributor
The UK electrical system is very different from the US/CAN system in several respects.
I recall reading that the UK system now has two different earthing systems.
Is it used in any modern installations (apart from Japan)?
blackmetalboon
Active Member
We have three main earthing systems;
TN-S (Earth and Neutral - Separate)
TN-C-S (Earth and Neutral - Combined - Separate) also known as PME (protective multiple earthing)
TT (Earth is the Earth)
Still widely used in rural areas where power is supplied by overhead lines.
This channel has lots of info about the UK electrical standards.
Speedskater
Major Contributor
Jim Brown has a lot of information on these different international earthing systems. Starting at page 39:
Power and Grounding For Audio and Audio/Video Systems -- A White Paper for the Real World
http://www.audiosystemsgroup.com/SurgeXPowerGround.pdf
Power and Grounding For Audio and Audio/Video Systems -- A White Paper for the Real World
http://www.audiosystemsgroup.com/SurgeXPowerGround.pdf
Down in audio frequencies I can believe that... and being picked up by some starquad in diff mode, not an antenna in an actual RF chamber. And I'm wondering if what you're seeing in that vid of the DAC 1's is the switching noise from the DAC circuitry coupling into the linear supply - I'd have to put it in my lab to see what's up. You can use a set of these:
https://www.tequipment.net/Beehive101A.html?Source=googleshopping
on a spectrum analyzer to locate where it's really coming from...
Also note - there's a difference in conducted emissions (ie.. how noisy a power supply is on the rails themselves) vs. radiated emissions from the components/units. This is why all the certs - including Mil STD 461 have separate tests for radiated and conducted. Conducted is done using a LISN (Line Impedance Stabilization Network. - Here's the 461 pic from another post:
As to the Smart Switcher, that's rated at 150mA for the +/- 15Vrails. I know some pro audio guys that have used those and love them. They're great for power opamp circuits... note where he states:
"The +/-15V linear regulators are fed by a dual switcher, working at a high frequency, so as to minimize radiated and conducted noise. Until recently this would not have been an option, but the linear post-regulators I selected have a PSRR of over 60dB at more than 1MHz! Absolutely incredible and exacty what is needed to clench what little ripple remains from the switcher. The 6/5/3.3 V source uses another dedicated high-frequeny switcher. It works in constant current mode into a relatively high decoupling cap and has low residual ripple. "
So at audio frequencies I can see it being fairly quiet... but talk to anyone that's had to do Part 15 or any other certs for their gear - it can be a nightmare...
I just spent an ungodly amount of time here:
http://thehowlandcompany.com/RDT-E_facilities/ASIL.htm
... with equipment that cost more than all the houses on my block, testing really high end SMPS's and most of them are a bit noisier than the linear stuff - again depending on the topology and load it's driving.
Typical SMPS in an LED lamp - just posted this on the forum somewhere else - this is a 7.5W LED lamp
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I had a micro seiki turntable and, my audiophile half getting the best of me, I replaced it with a high mass design, and then made an isolation platform (springs are astounding at reducing heavy vibrations getting to the turntable!). Along the way I used a seismometer/vibration monitoring app so I could actually see and record objective differences in reducing vibration. Objectively speaking, outside structure-born vibrations getting to the platter are way reduced with the high mass platter/isolation bass vs my micro seiki set up.
Sonically? I have no idea whatsoever if this fact is responsible for the improvement in sound quality I seem to experience between the old and new turntable set up. No way to do a back and forth in any practical way. And I'd say mostly it was an exercise in "scratching a mental itch" (a simple thought that cartridges pick up minute vibrations = spurious vibrations are bad, get rid of them!)
My experience, though, is that I never knew vinyl could sound as good as it does since I upgraded my system. I went from a slightly nostalgic vinyl sound (higher background noise, "warm" slightly thickened sound, tending to get a bit fuzzy/congested in complex source material) to something that competes surprisingly well with my digital source in terms of perceived sound quality. The general background noise floor on records went down vs my micro seiki set-up, and on decent pressings, it's just effortless to hear everything in a mix similar to listening to my digital source.
From: https://www.lexico.com/en/definition/electrocute
Oxford:
electrocute
past tense: electrocuted; past participle: electrocuted
- injure or kill someone by electric shock.
I stand corrected then
Measuring your homes earthing resistance, electrocuting people, measuring power supply emissions in a super high tech secret military lab.....
Wow! You guys sure know how to have a good time!
I thought that hanging around with much younger women from California in hot tubs was fun, but it got old much faster than you'd think.
My life needs a major rethink.
Wow! You guys sure know how to have a good time!
I thought that hanging around with much younger women from California in hot tubs was fun, but it got old much faster than you'd think.
My life needs a major rethink.
