Measuring EMF - the TriField TF2 meter

[ddk]

The "typical issues" include excessive magnetic fields and RF, which in my experience affect the sound of our systems, quite significantly in fact. The audible effects will vary by each component's architecture and setup, with phono being the most sensitive, by definition. Therefore, how one's system is affected by hum and RF cannot be easily predicted, but can be investigated. Having dealt with these issues for over 5 years now and documented under my system thread, my impression is that is a neglected subject, and power conditioning is only a part of the solution.

The technique is rather simple: run it around your components, power outlets, and all nearby appliances. Observe how the magnetic fields' magnitude drop (or not) as you move away, from one component to the other. RF from the outlets will seep into your power supplies, whether we like it or not. WiFi is everywhere, and you notice it as chirping (quick pulses) on the device. My Mac laptop emits a lot of RF from its lower-left corner... etc...

In my system, and long before I bought this device, every time I shielded things the sound became clearer, more realistic and more dynamic - that's what I was hoping for. This device, and others like it, enable one to wave it around and determine where interference may be coming from and what the nature and amplitude is.

The real cost, again, is what do you do with that information: Do you change or move cables? Do you buy power conditioning? Do you move components farther away? Do you shield things, including tubes? etc...

Let me discuss a few of my solutions:

Digital Cables: I have found out that there are significant differences that go beyond cable reflections, and have to do with shielding of RF noise. A classic example of this was the latest generation of Transparent's SPDIF cable a few years ago, only to discover that its position in the air affected its performance and the Vivaldi 2.0 DAC would lose its lock to the transport. By contrast, replacing it with an MIT or Kimber fixed the problem.

Analog and speaker interconnects: I have gained sizable improvements by mumetal+copper-shielding the MIT boxes. More than that, I have seen interconnects discussed on this forum that go beyond the typical copper-mesh shielding and include a mumetal jacket, to shield both against RF and low-frequency hum. They are expensive, but I bet they ought to sound really clear.

Power cords: I'll just state the obvious, off the shelf "stock" power cords emit large magnetic fields; I bet they also act as antennas. Run a few of them close to each other, and the magnitude of the magnetic fields multiplies. Havoc. Chaos. By contrast, the power cords I buy are heavily shielded. The gains ought to be both in the construction of the cord conductors as well as the magnetic fields they do not emit.

Phono: with respect to my heavily shielded Pass XP-25 phono: night and day; ability to turn up gain to its native 76dB, ability to load at 47K, no hum or hiss at very high listening volumes; therefore, a much more dynamic and accurate sound... I am currently helping another fellow here with shielding his own XP-25 and he says he's thrilled with the results.

Cartridge: obvious interference pick up from nearby magnetic fields

Power Conditioning: if you can reduce power-line noise with no loss of current flow, I'd call that a winner. I am able to plug everything into the Denali, including my current-hungry amps. Staggering performance gains all around, analog and digital. I feel this is the new dawn of power conditioning products. The downside with such proper power conditioning can be that it may expose problems in one's system, otherwise masked by noise running through the components, a masking that's typically rendered as softness and lack of resolution which some folks like (they may even call it 'natural'), midrange glare that they think is in the recording, musical notes that are way off or exaggerated, etc. Such issues exposed by power conditioning are typically: a) ill-attributed to power conditioning; and b) may be resolved with more expensive and better-engineered products... that's not to say that there aren't bad power conditioning products that impose their own problems and are just not worthy.

Tubes: I don't do tubes (so not my solution per se), but I have a friend who's copper-shielded all his tubes (some two-dozen) and he claims his system has never sounded so clean before. He's gained the most out of shielding his phono tubes, he says. He just hates the fact there is no more tube glow to look at.

Bottom line: noise is everywhere; noise is a killjoy; noise has no business in a high-performance audio system, if you look at it from the instrumentation point of view (which I do). Noise management is not discussed or addressed to the degree it deserves.

-ack

Perhaps instead of speculating about what other folks hear you should think about why you have to mummy wrap everything!

david

 

[ack]

Copper tape will dramatically change the sound of an armtube

I shudder to think how dramatically the copper tape will change the sound signature of an ebony armtube, Besides, it will do virtually nothing for the magnetic component of the field.

Regarding the wholesale application of mu-metal for screening purposes i'd be very careful. IME it sometimes does more damage than good.

Interestingly, even a conservative manufacturer such as ARC acknowledges this when they offer a light, acoustically transparent top covers for their preamps in lieu of steel.

Yes, I agree with all of that. Regarding mu-metal, yes, the reshaping of a magnetic field can sometimes be a problem.

 

[ack]

Havoc. Chaos? Definitely not sonically! Seems you make things up as you go along.

Your statement on what some folks may call lack of resolution as natural is basically your limited understanding of the subject and if there’s any ignorance here on natural sound it’s only on your part not understanding it. Perhaps you should stick to your wrapping instead of pretending of having a clue as to what some folks hear after all you wouldn’t have to mummy wrap and tweak everything if you got it right to begin with !

david

STAY OUT of this

 

[ddk]

STAY OUT of this

I’m only responding to your comments DON’T take unnecessary swipes and I’ll have no interest here!

david

 

[ack]

I’m only responding to your comments DON’T take unnecessary swipes and I’ll have no interest here!

david

GET OUT NOW - you are not addressing "comments" you are attacking a person directly, using "you" and other direct language.

 

[ddk]

GET OUT NOW - you are not addressing "comments" you are attacking a person directly, using "you" and other direct language.

Since the comments are yours I’m responding to you, not attacking. Since you’re sensitive let me change my response;

- There’s no need for mummy wrapping gear if right decisions were made from the start.
-People don’t call low rez sound with glare natural as stated in your post, simply untrue.
- Using high quality off the shelf powercords doesn’t create havoc and chaos unsubstantiated claims do.

Feel free to respond!

david

 

[ack]

- There’s no need for mummy wrapping gear if right decisions were made from the start.

This is a rather wide-reaching comment. If you mean that components should be spread far apart, I agree, but this may not be the case in tight spaces. Moreover, as I have found out, some components are just not built well enough, e.g. 1) MIT cable boxes (e.g they claim 5 shields in their latest top phono offering - I wrote to them about my findings years ago; others on this site have also successfully shielded their own MITs); 2) the XP-25 phono (a monster for noise pickup, as proven time and time again); and 3) and stock power cords (those that typically come with the equipment); this list is incomplete.

With respect to the XP-25, there are plenty of posts out on the internet with folks shielding it with steel plates over and under the main unit, and other ways. In addition, I have seen posts in the past that getting to 76dB gain on this unit is highly unlikely because of the excessive noise, so I may be the only one there.

Specific to my Spectral amps, the factory has said again and again to keep them far away from magnetic fields, including bad power cords (and their own stock cords are not good either; in fact, they recommend that one uses a "good" after-market cord)

-People don’t call low rez sound with glare natural as stated in your post, simply untrue.

I have seen a few folks who overuse the term "natural" when their systems have obvious and serious problems, at least from this perspective

- Using high quality off the shelf powercords doesn’t create havoc and chaos unsubstantiated claims do.

The key is in "high quality" - I don't see that in stock cords that come with the equipment. I've been measuring magnetic fields around power cords in my system for over a decade, using those devices that electricians employ to determine live wires and outlets, and when one piles them on in tight places, it is a mess, quite audible as well, plus you also see the effect in the FM tuner's Multipath meter. It is a wide-ranging effect.